Synthesis, X-ray crystallographic, spectroscopic and computational studies of aminothiazole derivatives

Journal of Molecular Structure 1131 (2017) 136e148

Contents lists available at ScienceDirect

Journal of Molecular Structure journal homepage: http://www.elsevier.com/locate/molstruc

Synthesis, X-ray crystallographic, spectroscopic and computational studies of aminothiazole derivatives Muhammad Adeel a, Ataualpa A.C. Braga b, Muhammad Nawaz Tahir c, Fazal Haq a, Muhammad Khalid d, *, Mohammad A. Halim e, f a

Department of Chemistry, Gomal University, Dera Ismail Khan, Khyber Pakhtun Khwa, Pakistan ~o Paulo, Av. Prof. Lineu Prestes, 748, Sa ~o Paulo, 05508-000, Brazil Departamento de Química Fundamental, Instituto de Química, Universidade de Sa University of Sargodha, Department of Physics, Sargodha, 40100, Punjab, Pakistan d Department of Chemistry, University of Education Lahore, Faisalabad Campus, Pakistan e Division of Quantum Chemistry, BICCB, Green Research Centre, 38 Green Road West, Dhaka, 1205, Bangladesh f Institut Lumi ere Mati ere, Universit e Lyon 1eCNRS, Universit e de Lyon, 69622, Villeurbanne Cedex, France b c

a r t i c l e i n f o

a b s t r a c t

Article history: Received 15 July 2016 Received in revised form 14 November 2016 Accepted 14 November 2016 Available online 15 November 2016

Aminothiazole organic compounds have diverse biological applications. Herein we report the synthesis of two aminothiazole derivatives: 4-(biphenyl-4-yl)thiazol-2-amine (1) and 4-(20 ,40 -difluorobiphenyl-4yl)thiazol-2-amine (2) via Suzuki-Miyaura cross coupling reaction. The chemical structures of 1 and 2 are confirmed using 1HNMR, 13CNMR, FT-IR, UVeVis and single crystal x-ray studies. The XRD study reveals that the both solid state structures (1) and (2) are diffused to form poly chain structures due to presence of intra molecular hydrogen bonding (H.B). Furthermore, these compounds were analysed by density functional theory (DFT) at M06-2X/6-311G(d,p), B3LYP/6-31G(d) B3LYP/6-31G(d,p) and B3LYP/6311G(2d,p) level of theories to obtain optimized geometry, electronic and spectroscopic properties. DFT optimized geometry supports the experimental XRD parameters. Natural bond orbital (NBO) calculation predicted the hyper conjugative interaction and hydrogen bonding in all derivatives. The FTIR and thermodynamic studies also confirm the presence of hydrogen bonding network in the dimers which agrees well with the XRD results. Moreover, UVeVis analysis reveals that maximum excitations take place in 1 and 2 due to HOMO / LUMO(98%) and HOMO / LUMO(97%) respectively which show good agreement to experimental data. The first order hyperpolarizability of both molecules is remarkably greater than the value of urea. The global reactivity parameters which are obtained by frontier molecular orbitals disclose that the molecules might be bioactive. © 2016 Elsevier B.V. All rights reserved.

Keywords: Aminothiazole Single crystal Density functional theory IR and Raman spectroscopy Hydrogen bonding Non-linear optical material

1. Introduction The thiazole ring consists of both sulphur and nitrogen are available in different and diverse molecules and they have extensive applications in agriculture and medicinal chemistry [1,2]. Thiazole heterocycles containing amine moiety have found applications in material science and these are used as building blocks in organic synthesis [3]. Varieties of biologically active molecules accommodate this interesting scaffold, aminothiazoles [4]. Aminothiazoles are used as important fragments in different drugs related to anti-tuberculosis,5 anti-inflammatory [5,6,7] anti-

* Corresponding author. E-mail address: [email protected] (M. Khalid). http://dx.doi.org/10.1016/j.molstruc.2016.11.046 0022-2860/© 2016 Elsevier B.V. All rights reserved.

allergic [8], anti-hypertensive [9], schizophrenia [10], antibacterial, HIV infections [5,11] and human lymphatic filarial parasites [12].Aminothiazoles are known ligands of estrogen and adenosine receptors antagonists [13]. Various aminothiazole derivatives are used as fungicides and herbicides and have numerous applications in agricultural field [14]. Alkyllated and arylated aminoacetyl derivatives of 2-amino-4phenylthiazolyl [15], 2-aminobenzothiazolyl [16], substituted 2amino-benzothiazolyl [17], 2-phenylamino-4-phenylthiazolyl [18], 2-amino-4-methylthiazolyl [19], as well as 3-aminobenzo[d]isothiazole derivatives [20] are found to have a potent local anaesthetic, anti-inflammatory, analgesic, and antipyretic activities [21]. Similarly, sulfonamides of aminothiazolesare used to treat bacterial infections, inflammations, tumours [22] and play a vital role in insulin release [23].

M. Adeel et al. / Journal of Molecular Structure 1131 (2017) 136e148

Although various aminothiazoles derivatives related to the substitution pattern and 4-(biphenyl-4-yl)thiazol-2-amine were synthesized and reported elsewhere [15e21]. However, according to the best of our knowledge, no studies regarding the title aminothiazole derivatives have been reported via Suzuki-Miyaura cross-coupling reaction. Herein, we report the synthesis of 4(biphenyl-4-yl)thiazol-2-amine and 4-(2',4'-difluorobiphenyl-4-yl) thiazol-2-amine employing Suzuki-Miyaura cross-coupling reaction (Scheme 1). The structures of synthesized compounds (1) and (2) were determined experimentally using 1HNMR, 13C NMR, and single crystal x-ray studies. Moreover, both compounds were studied by density functional theory (DFT) [24,25]. DFT is broadly used to determine the molecular geometry, electronic properties including frontier molecular orbitals (FMOs), natural bond orbital (NBO), non-linear optics (NLO), and molecular electrostatic potential (MEP) and spectroscopic analysis such as FT-IR, FT-Raman, UVeVis, and non-linear optics of organic molecules [26e29]. The main focus of the current study is to provide a detail structural and spectroscopic insight of the 4-(biphenyl-4-yl)thiazol-2-amine and 4-(2',4'-difluorobiphenyl-4-yl) thiazol-2-amine with the aid of experimental and theoretical techniques. 2. Experimental and calculation section 2.1. Reagents and instruments All reagents were obtained from Acros Organics and in analytically pure grade. NMR spectra were recorded using a BrukerAdvance spectrometer operating at 400 MHz for 1HNMR and 100 MHz for 13C NMR with tetramethylsilane as the internal standard. Chemical shifts are given in ppm (d-scale). The experimental FT-IR spectra of both compounds were performed by Perkin Elmer spectrum version 10.4.3. Melting points were measured on a digital melting point apparatus, Stuart, SMP10, U.K. and uncorrected. 2.2. XRD studies X-ray diffraction data was collected at room temperature by using Bruker Kappa APEX II CCD diffractometer with a graphite monochromator MoKa radiation (l ¼ 0.71073 Å). This X-ray diffraction data was used to determine structures of compounds (1) and (2). All crystallographic parameters, structure refinement and conditions for data collections are given in Table 1. Several different programs like APEX 2 used for data collection, SAINT for cell refinement and SAINT was used for data reduction. SHELXS97 program was used to solve structures. SHELXL97 program was used to refine structures. For molecular graphics ORTEP-3 for Windows, PLATON and Mercury 3.6 software were used. All the H atoms were positioned geometrically (CeH ¼ 0.93 A) and refined as riding with iso(H) ¼ xUeq(C), where x ¼ 1.2 for aryl H atoms. All non-hydrogen atoms were refined anisotropically. The positions of all hydrogen atoms were generated geometrically (Csp2-H ¼ 0.93 Å), assigned

137

isotropic thermal parameters, and allowed to ride on their respective parent carbon atoms before the final cycle of full-matrix least-squares refinement including 169 and 175 variable parameters for 1 and 2 respectively. Supplementary crystallographic data are deposited as CIF files at Cambridge Crystallographic Data Centre (CCDC ¼ 1483070 for 1 and 1483071 for 2). 2.3. Computational procedures Theoretical studies were executed with Gaussian 09program package [30] employing density functional theory (DFT) [31e35].The initial geometry for the both derivatives (1) and (2) was retrieved from the single crystal structures. Full optimization of 1 and 2 was carried out by B3LYP/6-31G(d), B3LYP/6-311 þ G(2d, p) and M06-2X/311G (d, p) level of theories. All frequencies of the two compounds are found real (positive) ensuring the optimized geometries corresponding to the true minimum in the potential energy surface. NBO, FMOs and MEP analysis of the thiazol derivatives were calculated at M06-2X/6-311G(d,p) level of theory. The FT-IR, FT-Raman, NLO properties and thermodynamic parameters were examined at B3LYP/6-311G(d,p) level of theory. An empirical scaling factor of 0.9627 [36] was used to counterpoise the systematic defects due to basis set deficiency, inconsideration of electron correlation and vibrational anharmonicity. Photophysical properties of these compounds were calculated by time dependent density functional theory (TD-DFT) at B3LYP/6-311G(d,p) level. The input files were organized utilizing Gauss View 5.0. [37] The Avogadro [38], Chemcraft [39] and Gauss View 5.0 programs were used to analyze the output files. 3. Results and discussion 3.1. Synthesis of 4-(biphenyl-4-yl)-1,3-thiazol-2-amine (1) In a screw capped reaction tube, 4-phenyl-1,3-thiazol-2-amine (100 mg, 0.48 mmol), Pd(PPh3)4 (8 mg, 1.5 mol%), phenyl boronic acid (136 mg, 0.531 mmol) and K3PO4 (153 mg, 0.724 mmol) were added to 3 mL of dioxane solvent. The resulting reaction mixture was flushed with dry nitrogen gas for few minutes. The reaction mixture was heated at 90e100  C for 8 h. After the completion of the reaction, 20 mL of water was added. After cooling at room temperature, organic and the aqueous layers were separated and the latter was extracted with ethyl acetate three times (3  15 mL). The obtained residue was then purified through column chromatography and compound (1) was isolated as dark yellow crystalline solid (95 mg, 85%). 3.2. Synthesis of 4-(2,4-difluorobiphenyl-4-yl)-1,3-thiazol-2-amine (2) In a screw capped reaction tube 4-phenyl-1,3-thiazol-2-amine (100 mg, 0.48 mmol), 4-phenyl-1,3-thiazol-2-amine, Pd(PPh3)4

Scheme 1. (i)Pd(PPh3)4, dioxane, K3PO4, 90e100  C, H2O.

138

M. Adeel et al. / Journal of Molecular Structure 1131 (2017) 136e148

Table 1 Single crystal XRD data of 1 and 2. Crystal data

Compound (1)

Compound (2)

CCDC Chemical formula Mr Crystal system, space group a, b, c (Å) Angle ( ) V (Å3) Z m (mm1) Data collection Diffractometer Absorption correction Tmin, Tmax No. of measured, independent and observed [I > 2s(I)] reflections Rint (sin q/l)max (Å1) Refinement R[F2 > 2s(F2)], wR(F2), S No. of reflections No. of parameters H-atom treatment Dr > max, Dr > min (e Å3)

1483070 C15H12N2S 252.33 Orthorhombic, Pccn 17.370 (2), 17.3704 (11), 8.2084 (12) a ¼ b ¼ g ¼ 90 2476.7 (5) 8 0.24

1483071 C15H10F2N2S 288.31 Monoclinic, P21/c 5.901 (1), 33.391 (6), 6.9745 (15) b ¼ 114.524 (10), a ¼ g ¼ 90 1250.3 (4) 4 0.27

Bruker Kappa APEXII CCD Multi-scan (SADABS; Bruker, 2005) 0.935, 0.951 8781, 2279, 1520 0.041 0.606

Bruker Kappa APEXII CCD Multi-scan (SADABS; Bruker, 2005) 0.932, 0.955 9392, 2327, 1227 0.093 0.606

0.047, 0.123, 1.01 2279 169 H-atom parameters constrained 0.19, 0.22

0.071, 0.196, 1.02 2327 175 H-atom parameters constrained 0.48, 0.48

Temperature (K) ¼ 296; Radiation type ¼ Mo Ka.

(8 mg, 1.5 mol%), 2,4-diflurophenyl boronic acid (153 mg, 0.724 mmol) and K3PO4 (153 mg, 0.724 mmol) were added to 3 mL of dioxane solvent. The resulting reaction mixture was flushed with dry nitrogen gas for few minutes. The reaction mixture was heated at 90e100  C for 8 h. After the completion of the reaction, 20 mL of water was added. After cooling at room temperature, organic and the aqueous layers were separated and the latter was extracted with ethyl acetate three times (3  15 mL). The obtained residue was then purified through column chromatography and compound (2) was isolated as light yellow crystalline solid (146 mg, 90%). 3.3. Single-crystal X-ray The aminothiazole derivatives were subjected to single-crystal X-ray diffraction. The information related to crystals is shown in Table 1 and hydrogen bond parameters are shown in Table 2. 3.4. Aminothiazole derivative (1) Aminothiazole derivative (1) crystallizes as dark yellow crystal in the orthorhombic space group Pccn having molecular formula C15 H12 N2 S and molar mass 252.33 amu. It is 1:1 adduct with no incorporation of the solvent molecule. Stoichiometry shows a discrete adduct formation [Fig. 1a (ORTEP diagram)]and polymeric chain structure (Fig. 1b) having hydrogen bond. The nitrogen atom of the thiazole group of one molecule serves as hydrogen bond acceptor and amino group on other molecule act as donor in the formation of dimeric structure of derivative (1). Several hydrogen bonds are present between the nitrogen and hydrogen of amino group of the thaizole ring which leads to a supramolecular structure (Fig. 1b). The observed hydrogen bonds information is summarized in Table 2.

Table 2 Selected hydrogen-bond parameters for 1 and 2. Compounds Atoms 1 2

DeH (Å) H/A (Å) D/A (Å)
N2eH2A /N1 0.88(4) N2eH2B/N1 0.94(5)

2.18(4) 2.10(6)

3.047(3) 2.975(6)

174(4) 156(5)

3.5. Aminothiazole derivative(2) The derivative (2) crystallizes as light yellow crystal having Monoclinic space group P21/c with Molecular formula C15 H10 F2 N2 S and molar mass 288.31 amu. The crystal stoichiometry is a discrete 1:1 adduct with no incorporated the solvent molecule [Fig. 2a (ORTEP diagram)] The derivative depicts distinct hydrogen bonding between hydrogen of the amino group and nitrogen of the thiazole ring as shown in polymeric chain structure (Fig. 2b). In this hydrogen bonding, the hydrogen of the amino group and nitrogen of the thiazole ring are involved. Data related to hydrogen bond, distances and angle are shown in Table 2. The dimeric structures of both derivatives have inter-molecular hydrogen bonds detected between N2eH2A$$$N1 and N2eH2B/N1 in 1 and 2 respectively. These distances are identified as 2.18 and 2.10 Å shown in Table 2. The inter-molecular hydrogenbonding arrangement provide insights of the dimeric structures which in turn transforms the compounds into supramolecular structures. 3.6. Geometric structures The geometrical parameters obtained by M06-2X/6-311G(d,p) [40,41] are compared with the experimental parameters summarized in Tables S1 and S2 (Supplementary information). The comparative study indicates that the experimentally determined bond lengths are slightly smaller than calculated bond lengths (Tables S1 and S2 in Supplementary information). This difference is expected because the experimental data correspond to the structures in solid phase. While, the DFT calculations associated to the gaseous phase. The DFT calculated bond lengths of the CeC bond of the both benzene rings in compound (1) are found between 1.386 and 1.398 Å. Whereas, experimentally, it ranges 1.362e1.389 Å which are much smaller as compared to the ordinary CeC single bond length (1.540 Å) and larger as compared to the C]C double bond (1.340 Å) [42,43]. The bond lengths of the CeC bond as shown C4eC10 and C15eC18 between the both benzene rings are found to be 1.482 and 1.474 Å for compound (1) and compound (2) respectively. These bond lengths are also smaller as compared to the

M. Adeel et al. / Journal of Molecular Structure 1131 (2017) 136e148

139

Fig. 1. (a) View of the title compound with the atom numbering scheme. The thermal ellipsoids are drawn at 50% probability level, the H-atoms are shown as small circles of arbitrary radii, (b) polymeric chains displaying hydrogen bond network.

ordinary CeC single bond length (1.540 Å). It is the evidence of conjugation between the both benzene rings. The bond lengths of the CeC bond in benzene rings of compound (1) are found to be slightly different than compound (2). This difference might be because of the fluoride group in compound (2) see Tables S1 and S2 (Supplementary information). The theoretically bond angles of compounds have also been investigated in the current study. The reasonable agreement is found between theoretically and experimentally determined bond angles as demonstrated in Tables S1 and S2 (Supplementary information). Both compounds were optimized at B3LYP/6-31G(d) B3LYP/6-311 þ G(2d, p) and M06-2X/6-311G(d, p) level of theories. Root mean square errors (RMSE) are calculated using geometric parameters which indicate slightly difference among these parameters as shown in Table S3.

3.7. Natural bond orbitals In X-ray, the polymeric structures (1b & 2b) have the N/HeN hydrogen-bonds (H-bond) as showed in Figs. 1 and 2. Therefore, NBO calculation [44,45] has been performed using dimeric structures to receive more orbital level insights on the nature and formation of the H-bonds in the two compounds. NBO study [46,47] also indicates the hyper conjugative interactions in the crystals

which are associated to intra-molecular donoreacceptor interactions. The stabilization energy E(2) [48e50] is obtained by analysing the relationship between the donoreacceptor interactions using the second-order perturbation theory using Equation (1).

E

ð2Þ


2 Fi;j ¼ qi εj  εi

(1)

Where: qi, i, j and Fi,j define orbital occupancy, diagonal, offdiagonal NBO Fock matrix elements [51] respectively. NBO results suggest that the donoreacceptor interactions are stabilized by the delocalization of the lone pair orbital (nN) of N32 LP (1) and N34 LP (1) towards the anti bonding orbitals (s*) of N3/H20 and N5/H23 in these compounds. As a result the second order perturbation stabilization energies are found to be 10.12 kJ mol1 and 9.69 kJ mol1 in compound (1) and compound (2), respectively as can be seen in Tables 3 and 4. This provides a reasonable explanation to the presence of hydrogen bonding (HB) net work in the dimeric structures in gas phase and solid state. The pictorial presentation of these NBOs is shown in Fig. 4. The stabilization energies have been determined as 7.51 and 6.98 kJ mol1 for the following transitions such as s(N35eH52)/ s*(S31eC50) and s(N3eH21)/s*(S1eC18) respectively in

140

M. Adeel et al. / Journal of Molecular Structure 1131 (2017) 136e148

Fig. 2. (a) View of the title compound with the atom numbering scheme. The thermal ellipsoids are drawn at 50% probability level, the H-atoms are shown as small circles of arbitrary radii, (b) polymeric chains displaying hydrogen bond network.

compounds (1) and (2) which show interactions for the hydrogen bonds between the sulfur and hydrogen of amino group (NeH/S), which also stabilized the supramolecular structure. 3.8. Hyperconjugative interactions The strong intra-molecular hyperconjugative interactions are found causing intra-molecular charge transfer (ICT) which in turn stabilize these compounds.

having ICT transitions i.e. p(N2eC18)/p*(C16eC17), p(C11eC12)/p*(C10eC15), p*(C13eC14), p(C13eC14)/ p*(C10eC15) and p*(C11eC 12) consist of E(2) i.e. 27.07, 27.63, 26.80, 29.63 and 28.40 kJ mol1 respectively (Table 3). Compound (2) containing ICT transitions i.e. p(N4eC20)/p*(C18eC19), p(C6eC7)/p*(C8eC9), p*(C10eC11), p(C10eC11)/p*(C6eC7) and p*(C8eC9) involving E(2) i.e. 25.39, 25.21, 34.49, 23.50 and 32.87 kJ mol-1 respectively (Table 4).

3.9. Intra-molecular interactions (s/s*) The stabilization energies have been determined as 5.39, 7.51, 4.14, 3.02 and 3.10 kJ mol1 from the following transitions such as s(N3eH20)/s*(N2eC18), s(N3eH21)/s*(S1eC18), s(C4eC5)/ s*(C4eC9), s*(C4eC10) and s*(C5eC6), respectively shown in Table 3. Compound (2) also shows such type of interactions as presented in Table S4 (Supplementary information). Hence, these interactions may contribute towards the stability of the electronic structure. 3.10. Intra-molecular interactions (p/p*) Interestingly, the p/p* interactions play prominent role to offer stronger stabilization in both compounds. Compound (1)

3.11. Intra-molecular interactions (LP/p*) The most important interaction energy in the two molecules is occurred due to the electron donation from N32 LP(1) and F35 LP(1) to the antibonding acceptor [N32eC48(p*)] and [N34eC50(p*)] resulting high stabilization energy of 51.98 and 51.30 kJ mol1 produced respectively (Tables 3 and 4). We report some representative interactions herein, other interactions are collected in Tables S4 and S5 (Supplementary information). From NBO analysis, we can infer that the strong intra-molecular hyper conjugation interactions and inter-molecular hydrogen bonding are responsible to yield more stability in these electronic structures in gas phase as well as in the solid-state structures.

M. Adeel et al. / Journal of Molecular Structure 1131 (2017) 136e148

141

Fig. 3. Optimized dimer (1) and (2) geometries calculated at M06-2X/6-311G(d,p) level of theory and showing hydrogen bond distances (angstrom) and atom labels.

3.12. FT-IR analysis

3.14. CeH vibration

The selective vibrational modes were assigned using the animation option of Avogadro software. These bands are systematized from small to high frequency along with specific assignments. The computed vibrational frequencies are scaled using the SQM approach are tabularized in Tables 5 and 6. A scale factor of 0.9627 is utilized to omit the anharmonicity effects [36].

The CeH stretching vibrational modes of hetero aromatic compounds are ranged between 3100 and 3000 cm1 [54]. In accordance with the current study, the CeH frequencies appeared in the range from 3160 cm1 to 3076 cm1 for 1 and ranged between 3160 cm1 and 3071 cm1 for 2 in FT-IR and their experimental FT-IR spectrum values are found to be 3111e2851 and 3111e2852 for 1 and 2 respectively (Tables 5 and 6).

3.13. CeC]C vibrations The vibrational bands of CeC in benzene derivatives appear at 1650-1400 cm1 [52,53]. In the current study, the bands are appeared in the range from 1605 to 1551 cm1 which shows good agreement with experimental 1634e1532 for 1 and from 1611 to 1596 cm1 for 2 which also shows good agreement with experimental1634-1531. Theirassignments are shown in Tables 5 and 6

3.15. NH2 vibration In the recent study, asymmetric and symmetric vibrational bands for NH2 of both molecules are appeared at 3552 and 3440 cm1. In the same way, experimental asymmetric and symmetric vibrational bands for NH2 of both molecules are found to be 3427 and 3279 cm1 see Tables 5 and 6

142

M. Adeel et al. / Journal of Molecular Structure 1131 (2017) 136e148

Table 3 Second order perturbation theory analysis of selected Fock matrix of dimer (1) using NBO method with M06-2X/6-311G(d,p) level theory. Donor NBO (i)

Type

Acceptor NBO (j)

Type

E(2)a

E(j)E(i)b

F(i,j)c

N3eH 20 N3eH21 C4eC5 C4eC5 C4eC5 N2eC18 C11eC12 C11eC12 C13eC14 C13eC14 N32 N32

s s s s s p p p p p

N2eC18 S1eC18 C4eC9 C4eC10 C5eC6 C16eC17 C10eC15 C13eC14 C10eC15 C11eC12 N3eH20 N32eC48

s* s* s* s* s* p* p* p* p* p* s* p*

5.39 7.519 4.14 3.02 3.10 27.07 27.63 26.80 29.63 28.40 10.12 51.98

1.37 0.94 1.40 1.31 1.42 0.44 0.36 0.37 0.35 0.35 0.83 0.38

0.077 0.076 0.068 0.056 0.059 0.102 0.091 0.090 0.091 0.090 0.093 0.132

LP(1) LP(1)

Energy of hyper conjugative interaction (stabilization energy), unit in kJ mol1 (a.u.). b Energy difference between donor and acceptor i and j NBO orbital. c Fock matrix element between i and j NBO orbital. a

Table 4 Second order perturbation theory analysis of selected Fock matrix of dimer (2) using NBO method with M06-2X/6-311G(d,p) level theory. Donor NBO (i)

Type

Acceptor NBO (j)

Type

E(2)a

E(j)E(i)b

F(i,j)c

N4eC20 C6eC7 C6eC7 C10eC11 C10eC11 N34 F35

p p p p p

C18eC19 C18eC19 C10eC11 C 6-C7 C8eC9 N5eH23 N34eC50

p* p* p* p* p* s* p*

25.39 25.21 34.49 23.50 32.87 9.69 51.30

0.45 0.35 0.34 0.38 0.37 0.98 0.37

0.100 0.084 0.098 0.085 0.100 0.089 0.131

LP (1) LP (1)

a Energy of hyper conjugative interaction (stabilization energy), unit in kJ mol1 (a.u.). b Energy difference between donor and acceptor i and j NBO orbital. c Fock matrix element between i and j NBO orbital.

3.16. Hydrogen bond vibrations The findings of XRD and NBO analysis suggest that both derivatives having hydrogen bonding pattern (N/HeN) see in Figs. 1e3 which drives them to construct the supramolecular structures. Hence, we performed IR absorption spectroscopy based on DFT analysis regarding monomers and dimers of both molecules with a particular objective to justify the H-bonding pattern. The scaled symmetric and asymmetric stretching vibrations for NH2 are found at [3439.819 cm1 (IIR ¼ 45.6388)] and 1 [3552.292 cm (IIR ¼ 29.1265)] in monomeric structure (1) and [3439.964 cm1 (IIR ¼ 46.5985)] and [3552.381 cm1

(IIR ¼ 29.5506)] in monomeric structure (2) respectively as can be seen in Fig. 5 (see also Tables S6 and S7 in the Supplementary information). Whereas, the both dimeric structures (1), and (2) displayed the NH2 band at 3290.04 cm1 with high intensity (IIR ¼ 827.4536)and 3231.061 cm1 with high intensity (IIR ¼ 703.8786) respectively. The lessening in vibrational frequencies and amplification in intensities are obtained in both dimeric structures. This is a clear proof of the existence of H-bonds in the investigated derivatives [55], as seen in Fig. 5 (see also Tables S6 and S7 in the Supplementary information). 3.17. UVeVisible analysis UVeVisible analysis was carried out to understand the nature of electronic excitations within 1 and 2 using TD-DFT-B3LYP/6311G(d,p) level of theory in a gas phase. The calculated wavelengths, electronic excitation energies, oscillator strengths and percentage of molecular orbitals are summarized in Tables S8 and S9 (Supplementary information). Table S8 shows that the magnitudes of maximum wavelengths [lmax (nm)] are obtained to be 304.86, 258.36 and 249.19 nm with oscillator strengths of 0.5702, 0.2302 and 0.1307 respectively for 1. Table S9 reveals that the extents of [lmax (nm)] are observed to be 306.46, 259.93 and 247.00 with oscillator strengths of 0.468, 0.3597 and 0.0887 respectively. Remaining electronic transitions as shown in Tables S8 and S9 are consisting of very low or zero extent of oscillator strengths (a dimensionless quantity that defines the capability of an electronic transition) which indicates forbidden electronic transitions. The oscillator strength for the transition at 304.86 nm is larger in extent as compared to other excitations is attributed to the excitation HOMO/ LUMO (98%). The compound 2 shows the transition at 306.46 nm can be assigned to the HOMO/ LUMO (97%) excitation. These transitions are contributed from pp* excitation. Moreover, the experimental maximum wavelengths [lmax (nm)] of both compounds were obtained in the ethyl acetate (ETOAc) which show good agreement to the calculated values as shown in Tables S8 and S9. 3.18. NMR analysis The 1H and 13C NMR chemical shifts values for 1 and 2 have been determined experimentally in CDCl3. While, 1H and 13C NMR chemical shift values were calculated for both compounds in the gas phase with b3lyp 6-311 þ G(2d, p). In the 1H NMR spectrum of 4-(biphenyl-4-yl)-1,3-thiazol-2amine (1), a broad singlet peak at 5.49 is due to NH2 protons, a singlet peak at 6.72 is assigned to CH proton of thiazole ring, a multiplet at 7.33 due to CH proton of phenyl ring, a multiplet at 7.40

Fig. 4. HB dimeric structures are constructed by the nitrogen and the anti-bonding orbital of the NH group interaction.

M. Adeel et al. / Journal of Molecular Structure 1131 (2017) 136e148 Table 5 Computed frequencies and assignments for vibrations of monomer (1) at B3LYP/6311G(d,p) level of theory. Frequency unscaled

Frequency scaled

Experimental frequency

Vibrational assignments

1372 1449

1321 1395

1259 1288

r CeHAromatþy CeN r CeHAromatþd

1489 1527 1544 1575 1611

1434 1470 1486 1516 1551

1337 1394 1456 1472 1532

1668

1605

1634

3195 3200 3202 3208 3226 3283 3573 3690

3076 3081 3083 3088 3106 3160 3440 3552

2851 2922 2959 3038 3093 3111 3279 3427

CeHAromat r CeHAromat r CeHAromat r CeHAromat r CeHAromat y(as)CeC]Cþb CeC] C y(s)CeC]Cþ (b) CeC]C y(as)CeHAromat y(s þ as)CeHAromatic y(s)CeHAromatic y(s)CeHAromatic y(s)CeHAromatic y CeHC]CHeS y(s)HNH2 y(as)HNH2

Frequencies are given in cm1, y ¼ stretching, b ¼ in-plane bending, d ¼ scissoring, r ¼ rocking, s ¼ symmetric, as ¼ asymmetric.

Table 6 Computed frequencies and assignments for vibrations of monomer (2) at B3LYP/6311G(d,p) level of theory. Frequency unscaled

Frequency scaled

Experimental frequency

Vibrational assignments

1176 1447 1475 1528 1549 1658

1132 1393 1420 1472 1492 1596

1261 1288 1304 1394 1471 1531

y CeF r CeHAromatþd CeHAromat r CeHAromat r CeHAromat r CeHAromat d CeHNH2 þy(s)CeC]Cþb

1665 1674 3189 3192 3206 3224 3227 3228 3282 3573 3690

1603 1611 3071 3073 3087 3104 3106 3107 3160 3440 3552

1614 1634 2752 2852 2924 2959 3088 3111 3279 3427

CeC]C y(s)CeC]C þb CeC]C y(s)CeC]C þb CeC]C y(as) CeHAromat y(as)CeHAromat y(s þ as)CeHAromatic y(s)CeHAromatic y(s)CeHAromatic y(s)CeHAromatic y CeHC]CHeS y(s)HNH2 y(as)HNH2

Frequencies are given in cm1, y ¼ stretching, b ¼ in-plane bending, d ¼ scissoring, r ¼ rocking, s ¼ symmetric, as ¼ asymmetric.

show 2 CH protons, 4 CH protons of aromatic ring are resonating as doublet at 7.59, a doublet at 7.80 is assigned to 2CH protons of phenyl ring. Similarly for 13C NMR spectrum of 4-(biphenyl-4-yl)1,3-thiazol-2-amine, the peaks at d ¼ 102.55, 126.63, 127.34, 127.04, 128.79 representing nine methine (CH) carbons while peaks at d ¼ 131.83, 137.67, 139.55, 149.81, 168.72 are assigned to quartenary carbons and peak observed at 168.72 is assigned to (CeNH2). In the 1H NMR spectrum of 4-(2,4-difluorobiphenyl-4-yl)-1,3thiazol-2-amine (2), a broad singlet peak at 5.02 is due to NH2 protons, a multiplet at 6.77 is assigned to CH proton of thiazole ring, a multiplet at 6.90e6.99 is due to 2 CH protons of phenyl ring, a doublet at 7.50 is showing two CH proton, 2 CH protons of aromatic ring are resonating as doublet at 7.82. Similarly for 13C NMR spectrum of 4-(2,4-difluorobiphenyl-4-yl)-1,3-thiazol-2-amine, the peaks at d ¼ 102.19, 115.68, 126.04, 126.54, 127.05, representing

143

eight methine (CH) carbons while peaks at d ¼ 130.13, 134.40, 136.34, 149.96, 159.68, 162.10, 168.72 are assigned to quartenary carbons and peak observed at 168.72 is assigned to (CeNH2). On the other hand, theoretical chemical shift values (1H and 13C NMR) were calculated of both compounds in the gas phase with b3lyp 6311 þ G(2d, p) which show deviation to experimental values might be because of medium affects as shown in Table 7. 3.19. Frontier molecular orbitals (FMOs) study DFT at M06-2X method with 6-311G(d, p) basis set is applied to compute the energy of HOMO and LUMO levels and the energies are shown in Table S10. The frontier molecular orbitals (FMOs) play a significant function in the electric and optical features, UVeVis spectra and quantum chemistry [56,57]. The pictorial demonstration of these different FMOs is shown in Figs. 6 and 7. The HOMO demonstrates the donor orbitals and the LUMO demonstrates acceptor orbitals [58]. The surface of FMOs is displayed to interpreting the bonding frame work of these compounds. Hence, six significant molecular orbitals have been investigated i.e. LUMO, LUMOþ1, LUMOþ2, HOMO, HOMO-1 and HOMO-2 demonstrate the respective acceptor and donor levels, two energy state above and two levels below respectively. The computed energy data of these six molecular orbitals and the corresponding energy gaps in gas phase are shown in Table S10. The energies of FMOs (LUMO & HOMO) have been used to investigate the global reactivity descriptors [59] using the equations given in the supplementary information. The chemical potential (m), global hardness (h), global softness (S) and global electrophilicity index (u) are known as global reactivity parameters [60e64]. These parameters are considered as highly successful descriptors for biological activity [65]. Moreover, electro negativity (X) [66] electron affinity (EA) and ionization potential (IP) [67] are also determined using the energies of frontier molecular orbitals. These reactivity parameters are also recently used in understanding the site selectivity and the reactivity [68e70].The compounds that possess positive electron affinity are known as electron acceptors and might participate in charge transfer reactions. The electron donation strength for any donor compound can be measured using its ionization potential is the energy which needed to take off an electron from the HOMO. Electro negativity is known as one of the most important chemical properties which define the power of specie to attract electrons towards itself. The large EHOMOeELUMO difference defines a hard specie, which means specie is more stable and less reactive. While, small EHOMOeELUMO gap defines a soft specie, which means specie is less stable and more reactive. The obtained findings indicate that the both molecules are less stable and more reactive see Table S11. 3.20. Molecular electrostatic potential (MEP) MEP plays a vital role in order to analyze the physical-chemical properties in chemical structures [71e74]. Electrostatic potential is enhanced in the order of red < orange < yellow < green < blue [75]. As seen from Fig. S6, the red colour in our dimers indicates the electron rich places as fluoride and nitrogen atoms. The blue colour indicates the electron deficient region as hydrogen atoms and some carbon atoms. MEP shows hydrogen bonding interactions which is in agreement with our experimental results as well as NBO analysis. 3.2.1. Non-linear optical (NLO) properties The organic compounds have become the centre of attraction due to their unique characters and potent potential applications in

144

M. Adeel et al. / Journal of Molecular Structure 1131 (2017) 136e148

Fig. 5. FT-IR absorption spectra calculated at B3LYP/6-311G(d,p) level of theory.

Table 7 Experimental and calculated 1H and

13

C NMR chemical shifts values for 1 and 2.

Number of atoms in 1

Experimental

DFT

Number of atoms in 2

Experimental

DFT

C C C C C C C C C C C C C C C H H H H H H H H H H H H

139.55 128.79 126.63 126.63 126.63 128.79 137.67 128.03 127.34 131.83 127.34 128.03 149.81 102.55 168.72 7.59 5.49 5.49 7.59 7.33 7.59 7.59 7.40 7.80 7.80 7.40 6.72

194.91 170.07 183.28 182.36 183.21 170.46 191.23 165.48 167.88 181.29 177.74 166.09 93.44 77.90 101.45 8.99 10.18 11.14 5.55 4.87 5.60 9.08 8.77 9.48 9.64 8.87 5.46

C C C C C C C C C C C C C C C H H H H H H H H H H

134.40 126.04 115.68 162.10 102.19 159.68 136.34 126.54 127.05 130.13 127.05 126.54 149.96 102.19 168.72 7.39e7.45 5.02 5.02 6.90e6.99 6.77 7.50 7.82 7.82 7.50 6.90e6.99

156.49 170.24 143.51 102.59 119.32 97.47 178.26 175.43 167.50 182.28 178.034 166.67 100.00 74.46 105.56 8.49 11.04 10.01 4.8 5.27 10.14 9.00 9.26 9.08 5.22

nonlinear optics (NLO), photonics and electronics [76e79]. The sketch of dynamic organic compounds for utilization in NLO response is established on the basis of asymmetric polarization. It is

directed through electron contributor and withdrawing groups on suitable location of the compound. The NLO response is enhanced with increasing the electron contributor and withdrawing groups

M. Adeel et al. / Journal of Molecular Structure 1131 (2017) 136e148

145

Fig. 6. Frontier molecular orbitals of 1. Energy in Hartree (a.u).

Fig. 7. Frontier molecular orbitals of 2. Energy in Hartree (a.u).


 〈a〉 ¼ 1 3 axx þ ayy þ azz



1 2 =



btot ¼ b2x þ b2y þ b2z btot ¼

bxxx þ bxyy þ bxzz

(4) 2

2  þ byyy þ byzz þ byxx

2  1 2  þ bzzz þ bzxx þ bxyz =

1 1 E ¼ E0  mi Fi  aij Fi Fj Fk  gijkl Fi Fj Fk Fl 2 24

(3)

=

efficiency attached to the p-conjugated system [80]. Therefore, we also studied NLO parameters of the p-conjugated molecules (1 & 2) using B3LYP level of theory with 6-311G (d, p) basis set. In finite field (FF) method, when specie is incorporated to a static field (F), the resulting energy (E) is represented by Equation (2).

(2)

Where E0 stands for the molecular energy in the nonattendance of electronic field.a, btot and g stand for polarizability, first and second hyperpolarizability tensors in x, y and z directions are calculated using Equations (3)e(6) respectively.

g¼

ii h 1h g þ gyyyy þ gzzzz þ 2 gxxyy þ gyyzz þ gxxzz 5 xxxx

(5)

(6)

The components of the dipole moment, total dipole moment,

146

M. Adeel et al. / Journal of Molecular Structure 1131 (2017) 136e148

the polarizability the first order and the second order hyperpolarizability values of both molecules are summarized in Table S12. The components of the dipole moment and polarizability of both molecules are different in all the directions as shown in Table S12. These components indicate the non-uniform charge distribution along the three directions. But the dipole moment and polarizability are found greater in extent for 2 than 1, might be due to the influence of fluoride groups on the skeleton of 2. The first order polarizability along x direction is around 98.67 a. u. It is larger than its y and z directions (positive directions) for 1. In the case of 2, the first order polarizability along x direction is 200 a. u. also larger than its y and z directions with negative directions. The second order polarizability along x directions for both molecules is larger than its y and z directions. They also indicate that both molecules are non-uniform distribution of the charges. The total dipole moment and polarizability, are found to be 1.95 a. u. (1) and 3.21 a. u. (2) and 1.48  1023 (esu) (1) and 1.63  1023 (esu) (2), respectively. The first order hyper polarizability and second order hyper polarizability are found to be 1.39  1030 (esu) (1) and 1.65  1030 (esu) (2) and 9.27  1029 (esu) (1) and 11.4  1029 (esu) (2) respectively see Table S12. All these parameters for 2 are greater in magnitude as compared to 1, might be due to electron withdrawing influence. Moreover, we compared our obtained parameters with urea compound because it is frequently used as reference molecule for comparative NLO analysis [78]. The total dipole moment of both molecules remarkably greater than the dipole moment of urea (For urea l ¼ 1.3732D). Similarly the first order hyperpolarizability of both molecules also remarkably greater than the value of urea (b ¼ 0.372  1030 esu).

the change molar entropy ðDS0m Þ for 1 is found greater than 2 which indicates the presence of relatively heavy groups (fluoride groups) in 2. 4. Conclusion In this study, two compounds including 4-(biphenyl-4-yl)thiazol-2-amine (1) and 4-(2',4'-difluorobiphenyl-4-yl)thiazol-2-amine (2) are synthesized and their structural information are obtained by 1 HNMR, 13C NMR, and single crystal x-ray techniques. The XRD studies suggest that the crystal structures of (1) and (2) are dark yellow-shaped having orthorhombic with space group Pccn and light yellow-shaped having monoclinic with space group P21/c respectively. Both structures show the hydrogen bonding network. This hydrogen bonding promote the supramolecular structures. Crystal structures of both compounds are compared with optimized structure calculated by DFT. NBO results predict that intramolecular charge transfer (ICT) and inter-molecular hydrogen bonding lead to stable dimeric structures. The FT-IR spectroscopic analysis and thermodynamic properties of monomers and dimers also confirm the hydrogen bond network. These non-bonding interactions are in good agreement with XRD results. UVeVis analysis reveals that maximum excitations take place from p-p* excitations. The global reactivity parameters which are calculated by frontier molecular orbitals indicate that these compounds are reactive. The first order hyperpolarizability is found to be 1.39  1030 (esu) for 1 and 1.65  1030 (esu) for 2. These values are 4 and 4.5 times greater as compared to the reference urea value (urea ¼ 0.3728  1030 esu), respectively which implies that these compounds may show non-linear optical properties. Acknowledgments

3.22. Thermodynamic properties The standard thermodynamic functions such as entropy (S), heat capacity at constant pressure (Cp) and enthalpy DH¼H(T)H(0) for monomeric and dimeric structures (1 & 2) based on vibrational analyses and statistical thermodynamics were obtained at temperature ranged from 25 to 1000 K using B3LYP/6-311G(d,p) level of theory in a gas phase as shown in Tables S13 and S14. Statistical thermodynamics calculations have key importance to processing properties as a function of temperature. Indeed, the molecular energies (produced from electronic excitations, molecular vibrational, translational and rotational motions) are transformed into entropies, heat capacities and enthalpies in statistical thermodynamics calculations. The entropies, heat capacities, and enthalpy changes are enhancing with temperature ranging from 25 to 1000 K. Mainly because, the molecular vibrational intensities increase with temperature. 0 Þ and The difference of molar entropy ðS0m Þ, heat capacity ðCp;m 0 Þ between monomeric and dimeric structures for 1 enthalpy ðDHm and 2 are calculated at 25 K using Equations (7) and (8).

DS0m ð25 KÞ ¼ S0mðdimerÞ  2*S0mðmonomerÞ

(7)

0 0 0 DDHm ð25KÞ ¼ DHmðdimerÞ  2*DHmðmonomerÞ

(8)

As a result, the change in molar entropy ðDS0m Þ, and enthalpy

0 Þ are 164.46 J/mol.K and 11.97 kJ/mol respectively for 1 as ðDDHm well as 162.77 J/mol.K and 12.88 kJ/mol respectively for 2. These differences reveal that the species containing non-covalent interactions (NCIs), may be due to the presence of hydrogen bonding in both dimmeric structures (1 &2). Further, the negative extent of

The authors are grateful to Sumaira Khalid for her valuable suggestions for a care full reading. Authors like to acknowledge Higher Education Commission (HEC), Pakistan for funding. We also acknowledge Dr. Ana Paula L. Batista for her cooperation. Appendix A. Supplementary data Supplementary data related to this article can be found at http:// dx.doi.org/10.1016/j.molstruc.2016.11.046. References [1] C. Hansch, P.G. Sammes, J.B. Taylor, in: Comprehensive Medicinal Chemistry, vol. 2, Pergamon Press, Oxford, UK, 1990 (Chapter 7).1. [2] M.D. McReynolds, J.M. Dougherty, P.R. Hanson, Synthesis of phosphorus and sulfur heterocycles via ring-closing olefin metathesis, Chem. Rev. 104 (2004) 2239e2258. [3] J.B. Baell, G.A. Holloway, New substructure filters for removal of Pan assay interference compounds (PAINS) from screening libraries and for their exclusion in bioassays, J. Med. Chem. 53 (2010) 2719e2740. [4] J.R. Lewis, Amaryllidaceae, Sceletium, muscarine, imidazole, oxazole, peptide and other miscellaneous alkaloids, Nat. Prod. Rep. 16 (1999) 389e416. [5] R.J. Nevagi, Biological and medicinal significance of 2-Aminothiazoles, Der. Pharm. Lett. 6 (2014) 134e150. [6] M.H.M. Helal, M.A. Salem, M.S.A. El-Gaby, M. Aljahdali, Synthesis and biological evaluation of some novel thiazole compounds as potential antiinflammatory agents, Eur. J. Med. Chem. 65 (2013) 517e526. [7] (a) F. Haviv, J.D. Ratajczyk, R.W. DeNet, F.A. Kerdesky, R.L. Walters, S.P. Schmidt, J.H. Holms, P.R. Young, G.W. Carter, 3-[1-(2-enzoxazolyl)hydrazino]propanenitrile derivatives: inhibitors of immune complex induced inflammation, J. Med. Chem. 31 (1988) 1719e1728; (b) F. Clemence, O.L. Marter, M. Mouren, R. Deraedt, 4-Hydroxy-3- quinolinecarboxamides with antiarthritic and analgesic activities, J. Med. Chem. 31 (1988) 1453e1462. [8] K.D. Hargrave, F.K. Hess, J.T. Oliver, N-(4-substituted-thiazolyl)oxamic acid derivatives, a new series of potent, orally active antiallergy agents, J. Med. Chem. 26 (1983) 1158e1163. [9] (a) M. Grimstrup, F. Zaragoza, Solid-phase synthesis of 2-Amino-5-

M. Adeel et al. / Journal of Molecular Structure 1131 (2017) 136e148

[10]

[11]

[12]

[13]

[14]

[15]

[16] [17] [18]

[19]

[20] [21]

[22]

[23]

[24]

[25]

[26]

[27]

[28]

sulfanylthiazoles, Eur. J. Org. Chem. (2002) 2953e2960; (b) W.C. Patt, H.W. Hamilton, M.D. Taylor, M.J. Ryan, S.R. Klutchko, I. Sircar, B.A. Steinbaugh, B.L. Bately, C.A. Painchand, S.T. Rapundalo, B.M. Michniewicz, S.C.J. Olzon, Structure-activity relationships of a series of 2-amino-4-thiazolecontaining renin inhibitors, J. Med. Chem. 35 (1992) 2562e2572. J.C. Jean, L.D. Wise, B.W. Caprathe, H. Tecle, S. Bergmeier, C.C. Humblet, T.G. Heffner, L.T. Meltzner, T.A. Pugsley, 4-(1,2,5,6-Tetrahydro-1-alkyl-3pyridinyl)-2- thiazolamines: a novel class of compounds with central dopamine agonist properties, J. Med. Chem. 33 (1990) 311e317. (a) S. Annadurai, R. Martinez, D.J. Canney, T. Eidem, P.M. Dunman, M.A. Gharbia, Design and synthesis of 2-Aminothiazole based antimicrobials targeting MRSA, Bioorg. Med. Chem. Lett. 22 (2012) 7719e7725; (b) F. Karci, A. Demircali, M. Yamac, Synthesis, solvatochromic properties and antimicrobial activities of some novel pyridone- based disperse disazo dyes, J. Mol. Liq. 187 (2013) 302e308. K.V. Sashidhara, K.B. Rao, V. Kushwaha, R.K. Modukuri, R. Verma, P.K. Murthy, Synthesis and antifilarial activity of chalconeethiazole derivatives against a human lymphatic filarial parasite, Brugia malayi, Eur. J. Med. Chem. 81 (2014) 473e480. J.E. Van Muijlwijk-Koezen, H. Timmerman, R.C. Vollinga, J.F. Von Drabbe Kunzel, M. De Groote, S. Visser, A.P. Ijzerman, Thiazole and thiadiazole analogues as a novel class of adenosine receptor antagonists, J. Med. Chem. 44 (2001) 749e762. S.E. Kazzouli, S.B. Raboin, A. Mouadbib, G. Guillaumet, Solid support synthesis of 2,4- disubstituted thiazoles and aminothiazoles, Tetrahedron Lett. 43 (2002) 3193e3196. K.V. Sashidhara, K.B. Rao, V. Kushwaha, R.K. Modukuri, R. Verma, P.K. Murthy, Synthesis and antifilarial activity of chalconeethiazole derivatives against a human lymphatic filarial parasite, Brugia malayi, Eur. J. Med. Chem. 81 (2014) 473e480. P.N. Bhargava, M.G.R. Nair, Anti-inflammatory activities of 2aminobenzothiazolyl derivatives, J. Indian Chem. Soc. 34 (1957) 42e45. P.K. Srivastava, P.N. Srivastava, Synthesis of some local anesthetics, J. Med. Chem. 13 (1970) 304e305. R. Lakhan, B.J. Rai, Local anaesthetics. IVeSynthesis and activity of 2-(Nsubstituted or N,N-disubstituted aminoacetamido)-4- or -4,5-substituted thiazoles, II Farm. Ed. Sci. 41 (1986) 783e788. A. Geronikaki, G. Theophilidis, Synthesis of 2-(aminoacetylamino)thiazole derivatives and comparison of their local anaesthetic activity by the method of action potential, Eur. J. Med. Chem. 27 (1992) 709e716. P. Vicini, L. Amoretti, M. Chiavarini, M. Impicciatore, II Farm. 41 (1990) 933e935. (a) N. Klose, K. Niedbolla, K. Schwartz, I. Bottcher, 4,5-Bis(4-Methoxyphenyl)2- cycloalkylthio-imidazole mit antiphlogistischer Wirkung, Arch. Pharm. 316 (1983) 941e951; (b) R.K. Satsangi, S.M. Zaidi, V.C. Misra, Pharmazie 38 (1983) 341e342; (c) E. Daniel Lynch, Ian McClenaghan, E. Mark Light, J. Simon Coles, The hydrogen-bonding networks of 2-amino-4-phenyl-1,3-thiazole derivatives, Cryst. Eng. 5 (2002) 123e136. (a) C.T. Supuran, A. Scozzafava, B.C. Jurca, M.A. Iiies, Carbonic anhydrase inhibitors - Part 49: synthesis of substituted ureido and thioureido derivatives of aromatic/heterocyclic sulfonamides with increased affinities for isozyme I, Eur. J. Med. Chem. 33 (1998) 83e93; (b) G. Renzi, A. Scozzafava, C.T. Supuran, Carbonic anhydrase inhibitors: topical sulfonamide antiglaucoma agents incorporating secondary amine moieties, Bioorg. Med. Chem. Lett. 10 (2000) 673e676; (c) J.J. Li, D. Anderson, E.G. Burton, J.N. Cogburn, J.T. Collins, D.J. Garland, S.A. Gregory, H.C. Huang, P.C.Isakson, 1,2-Diarylcyclopentenes as selective Cyclooxygenase-2 inhibitors and orally active anti-inflammatory agents, Med. Chem. 38 (1995) 4570e4578; (d) K. Asada, M. Watanabe, T. Nagasu, T. Tsukahara, K. Lijima, A.K. Kitoh, Novel sulfonamides as potential, systemically active antitumor agents, J. Med. Chem. 35 (1992) 2496e2497. (a) A.K. Gadad, C.S. Mahajanshetti, S. Nimbalkar, A. Raichurkar, Synthesis and antibacterial activity of some 5-guanylhydrazone/thiocyanato-6-arylimidazo [2,1-b]-1,3,4- thiadiazole-2-sulfonamide derivatives, Eur. J. Med. Chem. (2000) 853e857; (b) V.S. Misra, V.K. Saxena, R.J. Srivastava, Indian Chem. Soc. (1982), 781-781; (c) F. Zani, P. Vicini, Arch. Pharm. (1998) 219e223; (d) T.H. Maren, Relations between structure and biological activity of sulfonamides, Ann. Rev. Pharmacol. Toxicol. (1976) 309e327. A.A.C. Braga, N.H. Morgon, G. Ujaque, F. Maseras, Computational characterization of the role of the base in the SuzukiMiyaura cross-coupling reaction, J. Am. Chem. Soc. 127 (2005) 9298e9307. A.A.C. Braga, G. Ujaque, F. Maseras, A DFT study of the full catalytic cycle of the SuzukiMiyaura cross-coupling on a model system, Organometallics 34 (2006) 3647e3658. G.M. Max, A.A.C. Braga, L. Agustí, G. Ujaque, F. Maseras, Computational perspective on Pd-Catalyzed CeC cross-coupling reaction mechanisms, Acc. Chem. Res. 46 (2013) 2626e2634. M. Prabhaharan, A.R. Prabakaran, S. Gunasekaran, S. Srinivasan, DFT studies on vibrational spectra, HOMOeLUMO, NBO and thermodynamic function analysis of cyanuric fluoride Spectrochim, Acta A 136 (2015) 494e503. A. Suvitha, S. Periandy, P. Gayathri, NBO, HOMOeLUMO, UV, NLO, NMR and vibrational analysis of veratrole using FT-IR, FT-Raman, FT-NMR spectra and

147

HFeDFT computational methods, Spectrochim. Acta A 138 (2015) 357e369. [29] J. Sherin, P.P. Leela, R. Hemamalini, S. Muthu, A.A. Al-Saadi, Spectroscopic investigation (FTIR spectrum), NBO, HOMOeLUMO energies, NLO and thermodynamic properties of 8-Methyl-N-vanillyl-6-nonenamideby DFT methods, Spectrochimica Acta Part A Mol. Biomol. Spectrosc. 146 (2015) 177e186. [30] M.J. Frisch, G.W. Trucks, H.B. Schlegel, G.E. Scuseria, M.A. Robb, J.R. Cheeseman, G. Scalmani, V. Barone, B. Mennucci, G.A. Petersson, H. Nakatsuji, M. Caricato, X. Li, H.P. Hratchian, A.F. Izmaylov, J. Bloino, G. Zheng, J.L. Sonnenberg, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J. Hasegawa, M. Ishida, T. Nakajima, Y. Honda, O. Kitao, H. Nakai, T. Vreven, J.A. Montgomery Jr., J.E. Peralta, F. Ogliaro, M. Bearpark, J.J. Heyd, E. Brothers, K.N. Kudin, V.N. Staroverov, R. Kobayashi, J. Normand, K. Raghavachari, A. Rendell, J.C. Burant, S.S. Iyengar, J. Tomasi, M. Cossi, N. Rega, J.M. Millam, M. Klene, J.E. Knox, J.B. Cross, V. Bakken, C. Adamo, J. Jaramillo, R. Gomperts, R.E. Stratmann, O. Yazyev, A.J. Austin, R. Cammi, C. Pomelli, J.W. Ochterski, R.L. Martin, K. Morokuma, V.G. Zakrzewski, G.A. Voth, P. Salvador, J.J. Dannenberg, S. Dapprich, A.D. Daniels, O. Farkas, J.B. Foresman, J.V. Ortiz, J. Cioslowski, D.J. Fox, Gaussian 09, Revision D.01, Gaussian, Inc., Wallingford CT, 2009. [31] A.A.C. Braga, G. Ujaque, F. Maseras, A DFT study of the full catalytic cycle of the SuzukiMiyaura cross-coupling on a model system, Organometallics 25 (2006) 3647e3658. [32] A.A.C. Braga, N.H. Morgon, G. Ujaque, F. Maseras, Computational characterization of the role of the base in the SuzukiMiyaura cross-coupling reaction, JACS 127 (2005) 9298e9307. s, G. Ujaque, F. Maseras, Computational [33] M.G. Melchor, A.A.C. Braga, A. Lledo perspective on Pd-Catalysed C-C cross coupling reaction mechanism, Accounts Chem. Res. 46 (2013) 2626e2634. [34] D. Guest, V.H. Menezes da Silva, A.P.L. Batista, S.M. Roe, A.A.C. Braga, O. Navarro, (N-Heterocyclic carbene)-palladate complexes in anionic mizorokieheck coupling cycles: a combined experimental and computational study, Organometallics 34 (2015) 2463e2470. [35] (a) P. Hohenberg, W. Kohn, Inhomogeneous electron gas, Phys. Rev. 136 (1964) 864e871; (b) W. Kohn, L. Sham, Self-consistent equations including exchange and correlation effects, Phys. Rev. 140 (1965) 1133e1138; (c) R.G. Parr, Y. Weitao, Oxford University Press, 1994. [36] M.A. Halim, D.M. Shaw, R.A. Poirier, Medium effect on the equilibrium geometries, vibrational frequencies and solvation energies of sulphanilamide, J. Mol. Struct. Theochem 960 (2010) 63e72. [37] M.J. Frisch, A.B. Nielsen, A.J. Holder, Gauss View User's Manual, Gaussian Inc., Pittsburgh, PA, 2000. [38] http://avogadro.cc/wiki/Main_Page. [39] Chemcraft, http://www.chemcraftprog.com. [40] D.A. Petersson, M.A. Allaham, A complete basis set model chemistry. II. Openshell systems and the total energies of the first-row atoms, J. Chem. Phys. 94 (1991) 6081e6090. [41] G.A. Petersson, A. Bennett, T.G. Tensfeldt, M.A. Allaham, W.A.J. Mantzaris, A complete basis set model chemistry. II. Open-shell systems and the total energies of the first-row atoms, J. Chem. Phys. 89 (1988) 2193e2218. [42] D.R. Lide Jr., A survey of carbon-carbon bond lengths, Tetrahedron 17 (1962) 125e134. [43] J.J. Nie, D.J. Xu, Photosynthesis and molecular structure of 2-Amino-3Hphenoxazin-3-one chinese, J. Struct. Chem. 21 (2002) 165e167. [44] Y. Matsumoto, J.I. Iwamoto, K. Honma, Contribution of the p electron to the NeH/O¼C hydrogen bond: IR spectroscopic studies of the jet-cooled pyrrolee acetone binary clusters, Phys. Chem. Chem. Phys. 14 (2012) 12938e12947. [45] S. Moon, Y. Kwon, Conformational stabilization of 1,3-Benzodioxole: anomeric effect by natural bond orbital analysis, J. Phys. Chem. A 105 (2001) 3221e3225. [46] F. Weinhold, C. Landis, Valency and Bonding, Cambridge University Press, Cambridge, 2005. [47] A.E. Reed, L.A. Curtiss, F. Weinhold, Intermolecular interactions from a natural bond orbital, donor-acceptor viewpoint, Chem. Rev. 88 (1988) 899e926. [48] A.E. Reed, F. Weinhold, Natural localized molecular orbitals, J. Chem. Phys. 83 (1985) 1736e1740. [49] A.E. Reed, R.B. Weinhold, F. Weinhold, Natural population analysis, J. Chem. Phys. 83 (1985) 735e746. [50] A.E. Reed, F. Weinhold, Natural bond orbital analysis of near-HartreeeFock water dimer, J. Chem. Phys. 78 (1983) 4066e4073. [51] S. Fatma, A. Bishnoi, A.K. Verma, Synthesis, spectral analysis (FT-IR, 1H NMR, 13 C NMR and UVevisible) and quantum chemical studies on molecular geometry, NBO, NLO, chemical reactivity and thermodynamic properties of novel 2-amino-4-(4- (dimethylamino)phenyl)-5-oxo-6-phenyl-5,6-dihydro4H-pyrano[3,2-c]quinoline-3-carbo nitrile, J. Mol. Struct. 1095 (2015) 112e124. [52] J. Mohan, Organic Spectroscopy Principle and Application, Narosa Publishing House, New Delhi, 2001. [53] S. Muthu, A. Prabhakaran, Vibrational spectroscopic study and NBO analysis on tranexamic acid using DFT method, Spectrochim. Acta A 129 (2014) 184e192. [54] G. Varsanyi, Assignment of Vibrational Spectra of Seven Hundred Benzene Derivatives, Academic kiaclo, Budapest, 1973.

148

M. Adeel et al. / Journal of Molecular Structure 1131 (2017) 136e148

[55] R.M. Silverstein, F.X. Webster, Spectrometric Identification of Organic Compounds, sixth ed., John Wiley & Sons Inc, New York, 2003. [56] I. Fleming, Frontier Orbitals, Organic Chemical Reactions, Wiley, London, 1976. [57] J.S. Percy, P. Leela, R. Hemamalini, S. Muthu, A.A. Al-Saadi, Spectroscopic investigation (FTIR spectrum), NBO, HOMOeLUMO energies, NLO and thermodynamic properties of 8-Methyl-N-vanillyl-6-nonenamideby DFT methods, Spectrochim. Acta A 146 (2015) 177e186. [58] G. Mahalakshmi, V. Balachandran, NBO, HOMO, LUMO analysis and vibrational spectra (FTIR and FT Raman) of 1-Amino 4-methylpiperazine using ab initio HF and DFT methods, Spectrochim. Acta A 135 (2015) 321e334. [59] S. Muthua, A. Prabhakaran, Vibrational spectroscopic study and NBO analysis on tranexamic acid using DFT method, Spectrochim. Acta A 129 (2014) 184e192. [60] R.G. Parr, L.V. Szentpaly, S. Liu, Electrophilicity index, J. Am. Chem. Soc. 121 (1999) 1922e1924. [61] R.G. Parr, R.A. Donnelly, M. levy, W.E. Palke, Electronegativity: the density functional viewpoint, J. Chem. Phys. 68 (1978) 3801e3807. [62] P.K. Chattaraj, U. Sarkar, D.R. Roy, Electrophilicity index, Chem. Rev. 106 (2006) 2065e2091. [63] A. Lesar, I. Milosev, Density functional study of the corrosion inhibition properties of 1,2,4-triazole and its amino derivatives, Chem. Phys. Lett. 483 (2009) 198e203. [64] N.R. Sheela, S. Muthu, S. Sampathkrishnan, Spectrochimica Acta Part A Mol. Biomol. Spectrosc. 120 (2014) 237e251. [65] R. Parthasarathi, V. Subramanian, D.R. Roy, P.K. Chattaraj, Electrophilicity index as a possible descriptor of biological activity, Bioorg. Med. Chem. 12 (2004) 5533e5543. [66] M.N. Tahir, M. Khalid, A. Islam, S.M.A. Mashhadi, A.A.C. Braga, Facile Synthesis, single crystal analysis, and computational studies of sulfanilamide derivatives, J. Mol. Struct. 1127 (2017) 766e776. [67] K. Fukui, Role of frontier orbitals in chemical reactions, Science 218 (1982) 747e754. [68] R. Parthasarathi, J. Padmanabhan, M. Elango, V. Subramanian, P. Chattraj, Intermolecular reactivity through the generalized philicity concept, Chem. Phys. Lett. 394 (2004) 225e230. [69] R. Parthasarathi, J. Padmanabhan, V. Subramanian, V. Sarkar, B. Maiti, P. Chattraj, Toxicity analysis of 33'44'5-pentachloro biphenyl through

chemical reactivity and selectivity profiles, Curr. Sci. 86 (2004) 535e542. [70] R. Parthasarathi, J. Padmanabhan, V. Subramanian, V. Sarkar, B. Maiti, P. Chattraj, Toxicity analysis of benzidine through chemical reactivity and selectivity profiles: a DFT approach, Int. Elect. J. Mol. Des. 2 (2003) 798e813. [71] J.S. Murray, K. Sen, Molecular Electrostatic Potentials, Concepts and Applications, Elsevier, Amsterdam, 1996. [72] E. Scrocco, J. Tomasi, in: P. Lowdin (Ed.), Advances in Quantum Chemistry, Academic Press, New York, 1978. [73] E. Scrocco, J. Tomasi, Electronic molecular structure, reactivity and intermolecular forces: an euristic interpretation by means of electrostatic molecular potentials, Adv. Quantum Chem. 11 (1979) 115e193. [74] F.J. Luque, J.M. Lopez, M. Orozco, Perspective on “Electrostatic interactions of a solute with a continuum. A direct utilization of ab initio molecular potentials for the prevision of solvent effects”, Theor. Chem. Acc. 103 (2000) 343e345. [75] G. Mahalakshmi, V. Balachandran, NBO, HOMO, LUMO analysis and vibrational spectra (FTIR and FT Raman) of 1-Amino 4-methylpiperazine using ab initio HF and DFT methods, Spectrochim. Acta A 135 (2015) 321e334. [76] (a) P.N. Prasad, D.J. Williams, Introduction to Nonlinear Optical Effects in Molecules and Polymers, JohnWiley & Sons, New York, 1991; (b) A. Sethi, R. Prakash, Novel synthetic ester of Brassicasterol, DFT investigation including NBO, NLO response, reactivity descriptor and its intramolecular interactions analyzed by AIM theory, J. Mol. Struct. 1083 (2015) 72e81. [77] H.S. Nalwa, S. Miyata, in: Nonlinear Optics of Organic Molecules and Polymers, CRC Press, Boca Raton, Florida, 1997. [78] S.R. Marder, B. Kippelen, A.K.Y. Jen, N. Peyghambarian, Design and synthesis of chromophores and polymers for electro-optic and photorefractive applications, Nature 388 (1997) 845e851. [79] Y. Shi, C. Zhang, J.H. Bechtel, L.R. Dalton, B.H. Robinson, W.H. Steier, Low (sube 1-Volt) halfwave voltage polymeric electro-optic modulators achieved by controlling chromophore shape, Science 288 (2000) 119e122. [80] M.R.S.A. Janjua, M. Amin, M. Ali, B. Bashir, M.U. Khan, M.A. Iqbal, W. Guan, L. Yan, Z.M. Su, A DFT study on the two-dimensional second-order nonlinear optical (NLO) response of terpyridine-substituted hexamolybdates: physical insight on 2D inorganiceorganic hybrid functional materials, Eur. J. Inorg. Chem. 4 (2012) 705e711.