prelims, contents pages

prelims, contents pages

Polyhedron 25, issue 15, 3 November 2006 www.elsevier.com/locate/poly Contents Papers Edmund Kwiatkowski, Grzegorz Romanowski, Waldemar Nowicki, Mare...

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Polyhedron 25, issue 15, 3 November 2006 www.elsevier.com/locate/poly

Contents Papers Edmund Kwiatkowski, Grzegorz Romanowski, Waldemar Nowicki, Marek Kwiatkowski Polyhedron 25 (2006) 2809 Dioxovanadium(V) complexes of Schiff bases derived from S-(+)-2-(aminomethyl)pyrrolidine and aromatic o-hydroxycarbonyl compounds: Synthesis, characterization and structure

Enrico Prenesti, Pier Giuseppe Daniele, Silvia Berto, Simona Toso Polyhedron 25 (2006) 2815

Two diastereomers, which differ in absolute configurations of chiral centres and in conformation of five-membered rings, in one crystal of N-(7-methylsalicylidene)-(S)-(2-pyrrolidynylmethyl)amine dioxovanadium(V).

Structure proposed for the complexes: (a) Cu(bipy); (b) Cu(bipy)2; and (c) Cu(bipy)3. The ligand is schematised for sake of simplicity.

Spectrum–structure correlation for visible absorption spectra of copper(II) complexes showing axial co-ordination in aqueous solution

Bojan Kozlevcˇar, Amalija Golobicˇ, Peter Strauch Polyhedron 25 (2006) 2824 Dynamic pseudo Jahn–Teller distortion in a compressed octahedral CuO6 complex

Elsevier Ltd.

N

N

N Cu

N a

The coordination sphere of cis-[Cu(C8H7O3)2(H2O)2] at 115 K, with three rhombic coordination axes, differs importantly from the room temperature one, where compressed axial axes were determined. The MSDA analysis confirms the vibrational disorder in the structure at high temperature, and its gradual freezing by decreasing temperature. These results are in agreement with the EPR data that also show the reversibility of this change. Based on the EPR data, a fdz2 g1 ground state is proposed, although the room temperature spectrum suggests a fdx2 y 2 g1 ground state, but with a small g3 value (close to ge).

N

N Cu N

Cu N

N

N

N

N

b

c

iv

Veysel T. Yilmaz, Fatih Yilmaz, Haydar Karakaya, Orhan Bu¨yu¨kgu¨ngo¨r, William T.A. Harrison Polyhedron 25 (2006) 2829 Silver(I)-barbital based frameworks: Syntheses, crystal structures, spectroscopic, thermal and antimicrobial activity studies Three AgI-barb coordination polymers have been reported. Na3[Ag3(l-barb)6] is a 3D mixed-metal complex, while {[Ag2(l-barb)2][Ag2(l-en)2] Æ 5H2O}n contains the barb dianion and features 2D grid-type layers, which are further connected by extensive hydrogen bonds resulting in a 3D

H.P.S. Chauhan, U.P. Singh, N.M. Shaik, S. Mathur, V. Huch Polyhedron 25 (2006) 2841 Synthetic, spectroscopic, X-ray structural and antimicrobial studies of 1,3-dithia-2-stibacyclopentane derivatives of phosphorus based dithiolato ligands Mixed 1,3-dithia-2-stibacyclopentane derivatives with phosphorus based dithiolato ligands of the types SCH2 CH2 SSbSðSÞPOGO {where G = •CH(Me)•CH(Me)• and •C(Me)2• C(Me)2•} and SCH2 CH2 SSbSðSÞPðORÞ2

Javier Martı´nez, Luis A. Adrio, Jose´ M. Antelo, Ma Teresa Pereira, Jesu´s J. Ferna´ndez, Jose´ M. Vila Polyhedron 25 (2006) 2848

Contents

framework with open channels. [Ag(barb)(l-bpe)]n consists of 1D helical chains connected by hydrogen bonds between barb ligands to form 2D supramolecular sheets, which are further linked by aromatic p–p stacking interactions into a 3D network. The barb ligand has been shown to be able to exhibit different coordination modes. Different coordination modes of barb are seen in Na3[Ag3(l-barb)6] and {[Ag2(l-barb)2][Ag2(l-en)2] Æ 5H2O}n. Antimicrobial studies of the title complexes were also performed. While barb and the other coligands did not show any significant antimicrobial activity, complexes 1–3 exhibited a wide spectrum of antimicrobial activity against selected bacteria and fungi.

{where R = Prn, Bun and Ph} have been synthesized and characterized by physicochemical and spectral [UV, IR, NMR (1H, 13C and 31P)] methods. The antimicrobial activities of these complexes were found in vitro against a number of microorganisms by the disc diffusion method and they were found to be better antimicrobial agents than the tested standard antibiotics (chloroamphenicol and terbinafin). The single crystal X-ray diffraction analysis of 1,3-dithia-2-stibacyclopentane 2, 3-butylenedithiophosphate revealed a monodentate mode of bonding of the dithiophosphate ligand in the complex.

The reaction of tetranuclear cyclometallated palladium thiosemicarbazone compounds with Ph2PCH2PPh2 and hydrochloric acid affords mononuclear palladacycles with a chelated diphosphine as 1:1 electrolytes.

New thiosemicarbazone palladacycles with chelating bis(diphenylphosphino)methane

Ph2 P Cl Me

Pd P Ph2

N HN

S NHMe

K. Shanmuga Bharathi, A. Kalilur Rahiman, K. Rajesh, S. Sreedaran, P.G. Aravindan, D. Velmurugan, V. Narayanan Polyhedron 25 (2006) 2859 Synthesis of new end-off l-phenoxo and bisl-acetato tri-bridged copper(II), nickel(II) and zinc(II) complexes: Spectral, magnetic, electrochemical and catalytic studies

A new end-off type acyclic ligand with two N-methyl piperazine arms, 2,6-bis[(4-methylpiperazin-1-yl)]-4-formylphenol [L] has been synthesized by a simple Mannich reaction. L crystallises in the triclinic space group P 1. The mono and binuclear complexes of Cu(II), Ni(II) and Zn(II) have been prepared. Spectral, magnetic, electrochemical and catalytic studies on the complexes have been carried out.

Cl

Contents

Katerina A. Thiakou, Vlasoula Bekiari, Catherine P. Raptopoulou, Vassilis Psycharis, Panagiotis Lianos, Spyros P. Perlepes Polyhedron 25 (2006) 2869 Dinuclear lanthanide(III) complexes from the use of di-2-pyridyl ketone: Preparation, structural characterization and spectroscopic studies

Denis Lima Guerra, Vanda Porpino Lemos, Claudio Airoldi, Roˆmulo Simo˜es Ange´lica Polyhedron 25 (2006) 2880 Influence of the acid activation of pillared smectites from Amazon (Brazil) in adsorption process with butylamine

Adrienne Thorn, Roger D. Willett, Brendan Twamley Polyhedron 25 (2006) 2891 Crystal structure of [(C2H5)2NH2]2[Cd3Br8(CdBr2)] Æ H2O: An augmented ribbon structure

Tarlok S. Lobana, Gagandeep Bawa, Ray J. Butcher, Ben-Jie Liaw, Chen W. Liu Polyhedron 25 (2006) 2897 Thiosemicarbazonates of ruthenium(II): Crystal structures of [bis(diphenylphosphino)butane][bis(pyridine-2-carbaldehydethiosemicarbazonato)] ruthenium(II) and [bis(triphenylphosphine)][bis(benzaldehydethiosemicarbazonato)] ruthenium(II)

The reactions between Ln(NO3)3 Æ xH2O (Ln = Pr, Eu, Tb, Er) and di-2-pyridyl ketone in a mixture of MeOH and EtOH give dinuclear nitrate complexes containing the monoanions of both the gem-diol and hemiacetal derivatives of the ketone as ligands. The ligands adopt the three shown coordination modes in every complex. The Eu(III) and Tb(III) complexes display an intense red and green emission, respectively, in the solid state, the photoluminescence being achieved by an indirect process (antenna effect).

v

+ Ln(NO3)3·xH2O N

C

N

O

MeOH-EtOH

OH

N

C

OMe

N

OMe

C

N

O

N

N

O

Ln

Ln

Ln

The pillared interlayered clays are prepared through charge-compensating cations exchange present in the interlayer space of the swelling clays with aluminum cations polymer. On calcining, the inserted cations polymers yield rigid, thermally stable oxide species, named pillars.

The decorated ½Cd3 Br8 n 2n ribbons in this structure consist of triple chains of edge-shared CdBr6 octahedra fringed with tetrahedral CdBr4 groups. The triple chains can be viewed as being excised from the parent hexagonal CdBr2 lattice by the action of the diethylammonium molecular scissors.

The first example of a ruthenium(II) complex (1) with a chelating diphosphine forming a stable seven membered P,P-chelate ring in the presence of a potentially tridentate pyridine-2carbaldehyde thiosemicarbazonate anion coordinating via N2, S-donor atoms is described.

Ph2 S P P Ph2

1

C

N

O Ln

N

Ru N S

Ln

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Valiollah Mirkhani, Majid Moghadam, Shahram Tangestaninejad, Bahram Bahramian Polyhedron 25 (2006) 2904

Contents

Efficient alkene epoxidation and alkane hydroxylation with sodium periodate catalyzed by Mn(salophen) supported on polystyrenebound 1,4-phenylenediamine is reported.

Polystyrene-bound 1,4-phenylenediamine as a heterogeneous axial ligand for Mn(salophen)Cl and its use as biomimetic alkene epoxidation and alkane hydroxylation catalyst with sodium periodate

NH

NH2

N N Mn O O

Garima Singh, Ajai K. Singh, John E. Drake, Michael B. Hursthouse, Mark E. Light Polyhedron 25 (2006) 2915 Synthesis and single crystal structure of a three coordinate complex of mercury(II) with 1(ethylthio)-2-(diphenylphosphino) ethane (L) prepared by a new simple method

Beatriz S. Parajo´n-Costa, Oscar E. Piro, Reinaldo Pis-Diez, Eduardo E. Castellano, Ana C. Gonza´lez-Baro´ Polyhedron 25 (2006) 2920 Crystal structures, spectroscopic characterization and theoretical calculations of the guanidinium and ammonium salts of the insulin-enhancing anion [VO2(dipic)])

Mohammad Shakir, Shama Parveen, Poonam Chingsubam, Katsuyuki Aoki, Shahper N Khan, Asad U Khan Polyhedron 25 (2006) 2929 Cation supported self-assembly of coordination polymers, [(H2en)(ntpMCl2)]n (M = ZnII, CdII, HgII) involving the tripodal acid, ntp: X-ray crystal structure and DNA binding studies on zinc helicate

The (P, S) ligand 1-(ethylthio)-2-(diphenylphosphino) ethane (L) is synthesized in good yield by reacting Ph2PLi with CH3CH2SCH2CH2Cl. Its complexation with Cu(I), Hg(II) and organometallic species of Ru(II) are explored. The single crystal structure of Hg(II) complex of L has been determined. It is found to be a three coordinate species. The geometry of Hg can be best described as trigonal planar. The Hg(1)–P(1) bond length is ˚ and the Hg–Br bond lengths are 2.415(1) A ˚ . There exists a weak 2.5152(6) and 2.5952(6) A secondary interaction between Hg and the S donor site of the ligand.

The guanidinium and ammonium salts of the bisoxodipicolinatevanadate(V) anion were synthesized and characterized by single-crystal X-ray diffraction and spectroscopic techniques. The optimized geometry of [VO2(dipic)]) and its corresponding harmonic vibrational frequencies were calculated using methods of the density functional theory. Hydrogen bonding interactions appear to be relevant in stabilizing their crystal structures.

A first report on the self-assembly of novel coordination polymers of the type, [(H2en)(ntpMCl2)]n [M = ZnII, CdII, HgII] resulting due to deprotonation of ntp, present as the zwitterion [NH+(CH2CH2COOH)2(CH2CH2COO))] in aqueous medium, by en leading to the formation of the ditopic anion ntp2), suggesting that H2en2+ acts as a cation template. The coordination polymers thus resulted involve [ntpMCl2]2) as building units stabilized via hydrogen bonding interactions. X-ray analyses on [(H2en)(ntpZnCl2)]n features four coordinate Zn2+ defined by two oxygen donors from ntp2) ligands and two chloride anions.

Contents

Miroslava Malarova´, Zdeneˇk Tra´vnı´cˇek, ˇ erna´k Radek Zborˇil, Juraj C Polyhedron 25 (2006) 2935 [Co(en)3][Fe(CN)6] Æ H2O and [Co(en)3][Fe(CN)6]: A dehydration process investigated by single crystal X-ray analysis, thermal analysis and Mo¨ssbauer spectroscopy

Yueh-Hua Wang, Maw-Cherng Suen, Hsun-Tsing Lee, Ju-Chun Wang Polyhedron 25 (2006) 2944 Syntheses and structural characterization of three new coordination polymers of [Ag(PPIA) Æ H2O]n, [Cu(PPIA)2 Æ 2H2O]n and [Zn(PPIA)2(H2O)2]n; PPIA = 3-pyridinepropionic acid

R. Kefi, C. Ben Nasr, F. Lefebvre, M. Rzaigui Polyhedron 25 (2006) 2953 Hydrothermal synthesis and characterization of a new zinc phosphate [Zn2.5(HPO4)2(PO4)][C6H10N2] Æ 5H2O

He´le`ne Casellas, Patrick Gamez, Jan Reedijk, Chiara Massera Polyhedron 25 (2006) 2959 Solvent control in the synthesis of Zn(II) and Cd(II) supramolecular compounds with N,N0 {2,4-di-[(di-pyridin-2-yl)amine]-1,3,5-triazine}ethylenediamine

vii

Single crystals of [Co(en)3][Fe(CN)6] Æ H2O (1) have been transformed to an anhydrous complex of [Co(en)3][Fe(CN)6] (2) by dynamic heating of (1) up to 150 °C in the solid state. X-ray structures have been determined in both cases.

The syntheses and crystal structures of three new coordination polymers of the type [Ag(PPIA) Æ H2O]n (PPIA = 3-pyridinepropionic acid) (1), [Cu(PPIA)2 Æ 2H2O]n (2), and [Zn(PPIA)2(H2O)2]n (3), are reported. Interestingly, the one-dimensional chain complex of 1 or the two-dimensional frameworks of 2 and 3 are also linked to form threedimensional networks through hydrogen bonds.

A novel two-dimensional zinc phosphate, has [Zn2.5(HPO4)2(PO4)][C6N2H10] Æ 5H2O been hydrothermally synthesized. The structure of this compound, determined by single crystal X-ray diffraction, represents the first one with a Zn/P ratio of 5/6. Solid-state 13C and 31P MAS NMR spectroscopies agree perfectly with the X-ray structure. Ab initio calculations allow the attribution of phosphorus and carbon signals to the independent crystallographic sites and to the various atoms of the organic groups.

The reactions of Zn(NO3)2 or Cd(NO3)2 with the ligand N,N0 -{2,4-di-[(di-pyridin-2-yl)amine]-1,3,5-triazine}-ethylenediamine yield mono or trinuclear coordination compounds under the same experimental procedure, depending on the nature of the solvent used, namely methanol or acetonitrile.

2.5 ZnO + 3 H3PO4 + C6H8N2 + 5 H2O [Zn2.5(HPO4)2(PO4)][C6 N2H10].5H2O + 2.5H2O

viii

Stefania Tanase, Martin van Son, Gerard A. van Albada, Rene´ de Gelder, Elisabeth Bouwman, Jan Reedijk Polyhedron 25 (2006) 2967 Self-assembly of extended structures through non-coordination intermolecular forces: Synthesis, crystal structures, and properties of metal complexes with 5-methyl-2-pyrazinecarboxylate

S.A. Chimatadar, T. Basavaraj, S.T. Nandibewoor Polyhedron 25 (2006) 2976 Mechanistic study of quinoliniumdichromate (QDC) oxidation of mercury(I) in aqueous sulfuric acid in the presence of micro amounts of palladium(II) – Autocatalysis in catalysis

Okan Zafer Yes¸ilel, Mustafa Serkan Soylu, ¨ lmez, Orhan Bu¨yu¨kgu¨ngo¨r Halis O Polyhedron 25 (2006) 2985 Synthesis and spectrothermal studies of vitamin B13 complexes of cobalt(II) and nickel(II) with 4-methylimidazole: Crystal structure of [Ni(HOr)(H2O)(4-Meim)3]2 Æ 5H2O The aquatris(4-methylimidazole)orotatocobalt (II), [Co(HOr)(H2O)(4-Meim)3], and bis[aquatris(4-methylimidazole)orotatonickel(II)] pentahydrate, [Ni(HOr)(H2O)(4-Meim)3]2 Æ 5H2O, have been synthesized and characterized by means of elemental analysis, thermal analysis,

James A.S. Howell Polyhedron 25 (2006) 2993 Structure and bonding in cyclic thiolate complexes of copper, silver and gold

Contents

The present paper describes the synthesis and characterization of several metal complexes with the ligand 5-methyl-2-pyrazinecarboxylate: [Co(mpca)2(H2O)2], [Ni(mpca)2(H2O)2], [Cu(mpca)2(H2O)] Æ 3H2O and [Fe(mpca)2(OH)2] Æ 2H2O. In all cases, the X-ray crystal structure analysis reveals extended structures formed by non-covalent intermolecular forces, such as hydrogen-bonding and/or p–p stacking interactions.

The kinetics of oxidation of mercury(I) with quinoliniumdichromate (QDC) in the presence of micro amounts of palladium(II) catalyst in aqueous sulfuric acid medium has been studied. The active species of oxidant, reductant and catalyst in the reaction medium were understood to be HCrO4  , [Hg2(SO4)HSO4]) and PdCl+, respectively. The autocatalysis by one of the products, chromium(III), was observed.

IR, UV–Vis and mass spectroscopic studies. The crystal structure of 2 was also determined by single crystal X-ray diffraction. The Co(II) and Ni(II) ions in [M(C5H2N2O4)(H2O)(C4H6N2)3] are chelated to the deprotonated N3 pyrimidine atom and to the carboxylate oxygen atom of the bidentate orotate dianion, and to the three nitrogen atoms of the 4-Meim ligands, and their octahedral geometries are completed by an aqua ligand. The thermal decomposition pathway of the complexes has been predicted with the help of thermal analysis (TG, DTG and DTA) and mass spectroscopic data.

The structure and bonding of cyclic thiolate complexes of copper, silver and gold has been examined by DFT calculation

Pd(II) QDC + 3 Hg(I)

Cr(III) + 3 Hg(II)

H N

OH 2

M H2O O

N

N

O C

O

+3 N

N

H

H3C

H3C

OH2

H2O

O

M = Co(II) and Ni(II)

H

H

H

N

M N

N

OH2 N N O

N

H3C N

H

O

CH3

O C

O

+ 3H2O

Contents

Joy Chakraborty, Brajagopal Samanta, G. Rosair, Volker Gramlich, M. Salah El Fallah, Joan Ribas, T. Matsushita, Samiran Mitra Polyhedron 25 (2006) 3006 Two new hydrothermally synthesised L–M–L type cobalt(II) hydrogen bonded co-ordination complexes with mixed ligands: Characterisation and magneto-structural correlation

Chang-Yan Sun, Li-Cun Li, Lin-Pei Jin Polyhedron 25 (2006) 3017 Dicarboxylate anion-dependent assembly of Co(II) and Ni(II) coordination polymers with 1,2-bis(4-pyridyl)ethane

Young Soon Kang, Jeong-Ho Son, In-Chul Hwang, Kyo Han Ahn Polyhedron 25 (2006) 3025 Synthesis of a bis(oxazoline)-N-carboxylate ligand and its Zn(II) complex that shows C–H  Cl hydrogen bonding

Russell Binions, Claire J. Carmalt, Ivan P. Parkin Polyhedron 25 (2006) 3032 Antimony oxide thin films from the atmospheric pressure chemical vapour deposition reaction of antimony pentachloride and ethyl acetate The reaction of antimony pentachloride and ethyl acetate under atmospheric pressure chemical vapour deposition conditions leads to the production of antimony (III) oxide thin films on glass and gas sensor substrates. Scanning electron microscopy (SEM)

Two new hydrogen bonded 2-D polymeric L–M–L type Co(II) metal coordination complexes have been synthesised under controlled hydrothermal condition and spectroscopically characterised. X-ray study reveals the presence of weak covalent and extensive inter/intra molecular H-bonding interactions within the chains responsible for polymeric network. Both the complexes are found to be weakly antiferromagnetic in nature corroborating well with their structures.

Using mixed ligands, five new coordination polymers were obtained. Complexes 1–4 possess different complicated 3D metal-organic frameworks, while complex 5 is of (4,4) 2D grid-like layers. These results show that the position of carboxylate groups greatly affects the structure of the complexes.

A novel N3O-type chelate and its Zn(II) complex are synthesized. The chelate is a branched type N3O ligand, (S,S)-[Bis{(4-isopropyl-4,5dihydrooxazol-2-yl)methyl}amino]acetic acid sodium salt, which was synthesized through a stepwise introduction of the oxazoline rings. The Zn(II) complex shows C–H  Cl–Zn hydrogen bonding both in the solid and solution states. A single crystal X-ray analysis of the Zn(II) complex supports the C–H  Cl–Zn hydrogen bonding, showing a microchannel structure.

indicated that an island growth mechanism predominated. X-ray photoelectron spectroscopy (XPS) revealed binding energy shifts of 20.6 eV for O 2s and 35.4 eV for Sb 4d. The films were X-ray amorphous. Energy dispersive X-ray analysis (EDXA) and electron probe microanalysis (EPMA) gave coherent elemental compositions indicating that single phase Sb2O3 was made, with negligible impurity levels. The films showed little optical reflectance (10%) and 65–75% total transmission from 400 to 800 nm. Gas sensing experiments indicated that the films responded best to a reducing gas at 400 °C.

ix

x

Markku Talja, Mika Polamo Polyhedron 25 (2006) 3039 Configurational isomerism in crystalline bis(amidopyridine)trichloro complexes of tantalum(V)

Ping Liu, Zhao-Xun Lian, Jiwen Cai Polyhedron 25 (2006) 3045 Solid–vapor reaction properties of copper(II) and cadmium(II) sulfonates with amines

Chih-Yu Wu, Yi Chen, Shiau-Yi Jing, Chen-Shiang Lee, Joydev Dinda, Wen-Shu Hwang Polyhedron 25 (2006) 3053 Reactions of diiron nonacarbonyl with pyrrolyl-, pyridyl- and thienyl-substituted azines: N•N bond cleavage, cyclometallation and C@N r and p-bonding

Contents

The structures of tantalum amidopyridine complexes were studied by X-ray diffraction. The seven-coordinated mononuclear bis(amidopyridine) complexes displayed configurational isomerism in the crystalline state. Distortions in the coordination polyhedra around the Ta center were evaluated.

Copper(II) and cadmium(II) sulfonates react with amine vapors and form stable monoamine-coordinated complexes. Single crystals can grow in situ via the solid–vapor reaction process.

The reactions of pyrrolyl, pyridyl and thienyl azines with Fe2(CO)9 yielded various types of diironhexacarbonyl complexes with different coordination modes, which resulted from (1) N•N bond cleavage, (2) cyclometallation, (3) diaza-bridge coordination, (4) r- and p-imine bridge coordination and (5) p-imine bridge coordination of the ligand.

C H

Polyhedron 25 (2006) 3066 One-pot self-assembly of trinuclear silver(I) clusters containing propargyl alcohols and bis(diphenylphosphino)methane (dppm) ligands

Fe2(CO)9

N

N

THF

2 H H N N

C

(OC)3Fe

C

N N

HC

N

C H

+ N

(OC)3Fe

A simple, safe and high yielding one-pot procedure for the synthesis of trinuclear silver(I) acetylide clusters containing propargyl alcohols HCBCCRR0 OH (R = R0 = H, Me; R = Me, R0 = Et) and dppm ligands is presented. The X-ray crystal structure of rac-[Ag3{l3-g1-CBCC(Me)(Et)OH}(l-dppm)3](NO3)2 Æ CH2Cl2 was determined and the luminescence properties of the complexes were studied.

N Fe(CO)3

N

Fe(CO)3

2a

Raquel Aroz, Fabian Mohr, Elena Cerrada, Edward R.T. Tiekink, Mariano Laguna

H C

N N

2b

Contents

Jian-Sheng Xu, Yue-Tao Zhang, Guang-Hua Li, Ying Mu, Shou-Hua Feng Polyhedron 25 (2006) 3071 Constrained geometry tetramethylcyclopentadienyl-phenoxy titanium complexes: Synthesis, structures and catalytic properties for ethylene polymerization The synthesis of a new bidentate ligand, 1(2-methoxyphenyl)-2,3,4,5-tetramethyl-cyclopentadiene (1), as well as its corresponding constrained geometry titanium complex,

2-tetramethylcyclopentadienyl-phenoxytitanium dichloride [(TCP)TiCl2, 2], was described. Complex 2 was synthesized by reaction of TiCl4 with the lithium salt of 1, followed by CH3Cl elimination at 65 °C. Molecular structures of 2 and a known complex, 2-tetramethylcyclopentadienyl-6-methyl-phenoxytitanium dichloride [(TCMP)TiCl2, IVd], were determined by single-crystal X-ray diffraction. When activated with AliBu3 and Ph3 Cþ BðC6 F5 Þ4  , complex 2 exhibits moderate catalytic properties for ethylene polymerization.

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