- Email: [email protected]
Novel synthesis of oxa[9]helicenes by Lawesson’s reagent-mediated cyclization of helical quinone derivatives
Tetrahedron Letters 52 (2011) 4518–4520
Contents lists available at ScienceDirect
Tetrahedron Letters journal homepage: www.elsevier.com/locate/tetlet
Novel synthesis of oxa[9]helicenes by Lawesson’s reagent-mediated cyclization of helical quinone derivatives Mohammad Salim a,b, Akira Akutsu a, Takao Kimura a, Masahiro Minabe a, Michinori Karikomi a,⇑ a b
Department of Material and Environmental Chemistry, Graduate School of Engineering, Utsunomiya University, Utsunomiya, Tochigi 321-8585, Japan Department of Chemistry, School of Physical Sciences, Shahjalal University of Science and Technology, Sylhet 3114, Bangladesh
a r t i c l e
i n f o
Article history: Received 9 May 2011 Revised 7 June 2011 Accepted 8 June 2011 Available online 18 July 2011
a b s t r a c t New oxa[9]helicenes which possess one furan ring have been readily prepared by reactive helical quinone with Lawesson’s reagent or phosphorus pentasulfide in good yields. The versatility of this protocol has been demonstrated with various substituted helical quinones. Ó 2011 Elsevier Ltd. All rights reserved.
Keywords: Helicene Quinone Lawesson’s reagent Oxahelicene
Helicenes and related helical compounds are of interest because of their applications in asymmetric synthesis,1 chiral recognition,2 and chiral materials,3 which is the result of their inherently asymmetric molecular structure. Presently, considerable research effort focuses on currently focused on heterohelicenes. In particular, thiaheterohelicenes, with benzene rings that are partially replaced by thiophene rings, have been extensively investigated by several groups.4 Conversely, oxaheterohelicenes, which are helically shaped benzanulated oxygen analogs, are less investigated.5 We have previously reported the synthesis of helical quinone 2a derived from 2-hydroxybenzo[c]phenanthrene (1a). The oxidative coupling reaction of 1a using CuCl(OH)-TMEDA proceeded regioand stereoselectively at C-1 to produce helical quinone as the sole product.6 In the synthesis and investigation studies of the helical molecules, we reacted 2a with Lawesson’s reagent (LR method A) or phosphorous pentasulfide (tetraphosphrous decasulfide, P4S10, method B) in reflux toluene. As the data (Table 1, entries 1 and 2) show, an unexpected intramolecular cyclization reaction proceeded to give the oxa[9]helicene derivative 3a (Scheme 1).7,8 In general, LR and P4S10 have been frequently used as a thionation reagent for a variety of carbonyl compounds.9,10 However, several exceptional or unusual results have been reported in the case ⇑ Corresponding author. Tel./fax: +81 286 6156. E-mail address: [email protected] (M. Karikomi). 0040-4039/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.tetlet.2011.06.033
of conjugated carbonyl compounds.11 In this Letter, we report a new protocol for the synthesis of 3 by the reductive cyclization of 2 using thionation reagents. Helical quinones 2a–e were synthesized by oxidative coupling of 2-hydroxybenzo[c]phenanthrenes (1a–e) using CuCl(OH)-TMEDA. The reaction of 2a with 2.0 equimolar amounts of LR under refluxing toluene for 15–20 h results in reductive cyclization. After a typical workup, oxa[9]helicene (3a) was isolated in 87% yield (Table 1, entry 1). We also examined the reaction of 2a with 2.0 equimolar amount of P4S10 in reflux toluene. The reaction proceeded smoothly and was completed in 5 h. The oxa[9]helicene (3a) was isolated in 72% yield (entry 2). To the best of our knowledge, the synthesis of furan derivatives by LR or P4S10 has not yet been reported. These methods have a general applicability and can be extended to the synthesis of various alkyl or bromo substituted and benzannulated oxa[9]helicene derivatives 3b–f (Table 1). The isolated 3 is identified and characterized by 1H, 13C NMR spectroscopy, IR spectroscopy, and mass spectroscopy.9 The conversion mechanism of 2–3 is not presently clear and the formation of 3 was an unexpected result of 2 under our reaction conditions. A plausible mechanism has as follows (Scheme 2): (i) LR and P4S10 are converted into 2 equimolar amounts of dithioxophosphoranes, which are common intermediates for the thionation reaction of carbonyl compounds; (ii) the dithioxophoshorane reacts with 2 by a conjugate addition reaction. Subsequent cyclization product (A) is captured by the other dithioxophoshorane to form intermediate B; (iii) nucleophilic
4519
M. Salim et al. / Tetrahedron Letters 52 (2011) 4518–4520 Table 1 Synthesis of oxa[9]helicene derivatives Entry
Substrate
Product
1 2
O
A B
87 72
A B
74 65
A B
42 34
A B
32 71
A B
38 59
A B
63 32
3a
3 4
Me Me
O
O
O
Me 3b
Me 2b 5 6
Et Et
O
O
O
Et 3c
Et 2c 7 8
t
Bu t
O
Bu
O
O t Bu 2d
t Bu 3d
9 10
O O
O
2e
3e
Br
Br
O Br
Yield (%)
O
O 2a
11 12
Method
O
Br
O 2f
3f
Method A: Lawesson’s reagent (2.0 equiv), toluene, reflux, 15–20 h. Method B: P4S10 (2.0 equiv), toluene, reflux, 2–5 h.
R 2
R
R
CuCl(OH)-TMEDA
1
R
O
air, CHCl3
OH
2 1
Lawesson's reagent or P4S10
R O
O 2
R 1
R
1
R
2
R
2
2
R
1
1
3
Scheme 1.
substitution by S-phosphonodithionate is caused the formation of 3 and C; (iv) the produced C is decomposed to form thiaphosphirane 3-sulfide (D) and dithioxophoshorane. This reaction mechanism is analogous to that proposed mechanism for the reaction of N-alkylhydroxamic acid with Lawesson’s reagent.11
In summary, we have demonstrated a novel and efficient reductive cyclization of helical quinone mediated by LR or P4S10 that produces oxa[9]helicenes. We can also characterize the molecular structure and spectroscopic properties by several analytical methods. Further studies on the synthesis of novel helical molecules are in progress in our laboratories.
4520
M. Salim et al. / Tetrahedron Letters 52 (2011) 4518–4520
S
SS
P
H 3 CO
P S S
OCH3
2
H 3 CO
P S
Lawesson's reagent S SS P
S S
P
P S
S
S
S
P
2
S
S
P
S P S
S
S P4S10
O O 2
S O
R P S
S
S
O
S
H
H
S P
S P
O
R
A
R P
P
O
S
B
S R
P S
S
O
O 3
R
S
R LR: R=CH3 OC 6H 4, P4S10: R=S2PS-
R P
S S S
S C
S
R P
O
+
R P S
S R P S O D
Scheme 2. Plausible mechanism.
Acknowledgment We thank Mr. M. Roppongi for the MS spectra (Collaboration Center for Research Development, Utsunomiya University). References and notes
5.
6. 7.
1. Kawasaki, T.; Suzuki, K.; Licandro, E.; Bossi, A.; Maiorana, S.; Soai, K. Tetrahedron: Asymmetry 2006, 17, 2050; (b) Takenaka, N.; Sarangthem, R. S.; Captain, B. Angew. Chem., Int. Ed. 2008, 47, 9708; (c) Sato, I.; Yamashima, R.; Kadowaki, K.; Yamamoto, J.; Shibata, T.; Soai, K. Angew. Chem., Int. Ed. 2001, 40, 1096; (d) Reetz, M. T.; Beuttenmüller, E. W.; Goddard, R. Tetrahedron Lett. 1997, 38, 3211; (e) Reetz, M. T.; Sostmann, S. J. Organomet. Chem. 2000, 603, 105; (f) Dreher, S. D.; Katz, T. J.; Lam, K.-C.; Rheingold, A. L. J. Org. Chem. 2000, 65, 815. 2. For a recent review on chiral recognition in helicenes, see: (a) Amemiya, R.; Yamaguchi, M. Org. Biomol. Chem. 2008, 6, 26; (b) Yamaguchi, M. J. Synthetic Org. Chem. 2011, 69, 17. 3. (a) Chen, C.-T.; Chou, Y.-C. J. Am. Chem. Soc. 2000, 122, 7662; (b) Ashitaka, H.; Yokoh, Y.; Shimizu, R.; Yokozawa, T.; Morita, K.; Suehiro, T.; Matsumoto, Y. Nonlinear Opt. 1993, 4, 281; (c) Lovinger, A. J.; Nuckolls, C.; Katz, T. J. J. Am. Chem. Soc. 1998, 120, 264. 4. (a) Bossi, A.; Falciola, L.; Graiff, C.; Maiorana, S.; Rigamonti, C.; Tiripicchio, A.; Licandro, E.; Mussini, P. R. Electrochim. Acta 2009, 54, 5083; (b) Kitahara, Y.; Tanaka, K. Chem. Commun. 2002, 932; (c) Torras, J.; Bertran, O.; Alemán, C. J. Phys. Chem. B 2009, 113, 15196; (d) Tian, Y.-H.; Park, G.; Kertesz, M. Chem. Mater. 2008, 20, 3267; (e) Okuyama, T.; Tani, Y.; Miyake, K.; Yokoyama, Y. J. Org.
8.
9. 10. 11.
Chem. 2007, 72, 1634; (f) Cpllins, S. K.; Vachon, M. P. Org. Biomol. Chem. 2006, 4, 2518. (a) Pieters, G.; Gaucher, A.; Marque, S.; Maurel, F.; Lesot, P.; Prim, D. J. Org. Chem. 2010, 75, 2096; (b) Spencer, D. D.; Daniel, J. W.; Katz, T. J. J. Org. Chem. 1999, 64, 3671; (c) Areephong, J.; Ruangsupapichart, N.; Thongpanchang, T. Tetrahedron Lett. 2004, 45, 3067. Karikomi, M.; Yamada, M.; Ogawa, Y.; Houjou, H.; Seki, K.; Hiratani, K.; Haga, K.; Uyehara, T. Tetrahedron Lett. 2005, 46, 5867. Typical procedure (method A): A solution of helical quinone 2 (48 mg, 0.10 mmol) and Lawesson’s reagent (41 mg, 0.10 mmol, 2 equiv) was refluxed for 20 h in toluene. The mixture was concentrated then separated by column chromatography on silicagel eluted by chloroform. 3a was obtained 41 mg (87% yield). (method B): A solution of helical quinone 2 (48 mg, 0.10 mmol) and phosphorus pentasulfide (P4S10) (22 mg, 0.050 mmol, 2 equiv) was refluxed for 5 h in toluene. The mixture was concentrated then purified by column chromatography on silicagel and eluted by chloroform. 34 mg of 3a was obtained (72% yield). Compound characterization: 3a: mp 310–314 °C; 1H NMR (CDCl3, 500 MHz) d: 5.72 (2H, t, J = 7.5 Hz), 6.19 (2H, d, J = 8.5 Hz), 6.76 (2H, t, J = 7.3 Hz), 7.31 (2H, d, J = 8.0 Hz), 7.37 (2H, d, J = 8.5 Hz), 7.57 (2H, d, J = 8.5 Hz,), 7.60 (2H, d, J = 8.5 Hz), 8.11 (2H, d, J = 8.5 Hz), 8.27 (2H, d, J = 8.5 Hz), 8.31 (2H, d, J = 8.0 Hz). 13C NMR (CDCl3, 100 MHz): 110.95, 121.02, 122.19, 124.03, 124.33, 124.62, 125.15, 125.34, 126.20, 126.27, 126.50, 126.93, 127.29, 127.61, 129.45, 129.51, 129.94, 154.22; HRMS (EI) calculated for C36H20O [M]+: 468.1514, found 468.1504. Ozturk, T.; Ertas, E.; Mert, O. Chem. Rev. 2010, 110, 3419. Ozturk, T.; Ertas, E.; Mert, O. Chem. Rev. 2007, 107, 5210. Przychodzen´, W. Eur. J. Org. Chem. 2005, 2002.
Contents lists available at ScienceDirect
Tetrahedron Letters journal homepage: www.elsevier.com/locate/tetlet
Novel synthesis of oxa[9]helicenes by Lawesson’s reagent-mediated cyclization of helical quinone derivatives Mohammad Salim a,b, Akira Akutsu a, Takao Kimura a, Masahiro Minabe a, Michinori Karikomi a,⇑ a b
Department of Material and Environmental Chemistry, Graduate School of Engineering, Utsunomiya University, Utsunomiya, Tochigi 321-8585, Japan Department of Chemistry, School of Physical Sciences, Shahjalal University of Science and Technology, Sylhet 3114, Bangladesh
a r t i c l e
i n f o
Article history: Received 9 May 2011 Revised 7 June 2011 Accepted 8 June 2011 Available online 18 July 2011
a b s t r a c t New oxa[9]helicenes which possess one furan ring have been readily prepared by reactive helical quinone with Lawesson’s reagent or phosphorus pentasulfide in good yields. The versatility of this protocol has been demonstrated with various substituted helical quinones. Ó 2011 Elsevier Ltd. All rights reserved.
Keywords: Helicene Quinone Lawesson’s reagent Oxahelicene
Helicenes and related helical compounds are of interest because of their applications in asymmetric synthesis,1 chiral recognition,2 and chiral materials,3 which is the result of their inherently asymmetric molecular structure. Presently, considerable research effort focuses on currently focused on heterohelicenes. In particular, thiaheterohelicenes, with benzene rings that are partially replaced by thiophene rings, have been extensively investigated by several groups.4 Conversely, oxaheterohelicenes, which are helically shaped benzanulated oxygen analogs, are less investigated.5 We have previously reported the synthesis of helical quinone 2a derived from 2-hydroxybenzo[c]phenanthrene (1a). The oxidative coupling reaction of 1a using CuCl(OH)-TMEDA proceeded regioand stereoselectively at C-1 to produce helical quinone as the sole product.6 In the synthesis and investigation studies of the helical molecules, we reacted 2a with Lawesson’s reagent (LR method A) or phosphorous pentasulfide (tetraphosphrous decasulfide, P4S10, method B) in reflux toluene. As the data (Table 1, entries 1 and 2) show, an unexpected intramolecular cyclization reaction proceeded to give the oxa[9]helicene derivative 3a (Scheme 1).7,8 In general, LR and P4S10 have been frequently used as a thionation reagent for a variety of carbonyl compounds.9,10 However, several exceptional or unusual results have been reported in the case ⇑ Corresponding author. Tel./fax: +81 286 6156. E-mail address: [email protected] (M. Karikomi). 0040-4039/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.tetlet.2011.06.033
of conjugated carbonyl compounds.11 In this Letter, we report a new protocol for the synthesis of 3 by the reductive cyclization of 2 using thionation reagents. Helical quinones 2a–e were synthesized by oxidative coupling of 2-hydroxybenzo[c]phenanthrenes (1a–e) using CuCl(OH)-TMEDA. The reaction of 2a with 2.0 equimolar amounts of LR under refluxing toluene for 15–20 h results in reductive cyclization. After a typical workup, oxa[9]helicene (3a) was isolated in 87% yield (Table 1, entry 1). We also examined the reaction of 2a with 2.0 equimolar amount of P4S10 in reflux toluene. The reaction proceeded smoothly and was completed in 5 h. The oxa[9]helicene (3a) was isolated in 72% yield (entry 2). To the best of our knowledge, the synthesis of furan derivatives by LR or P4S10 has not yet been reported. These methods have a general applicability and can be extended to the synthesis of various alkyl or bromo substituted and benzannulated oxa[9]helicene derivatives 3b–f (Table 1). The isolated 3 is identified and characterized by 1H, 13C NMR spectroscopy, IR spectroscopy, and mass spectroscopy.9 The conversion mechanism of 2–3 is not presently clear and the formation of 3 was an unexpected result of 2 under our reaction conditions. A plausible mechanism has as follows (Scheme 2): (i) LR and P4S10 are converted into 2 equimolar amounts of dithioxophosphoranes, which are common intermediates for the thionation reaction of carbonyl compounds; (ii) the dithioxophoshorane reacts with 2 by a conjugate addition reaction. Subsequent cyclization product (A) is captured by the other dithioxophoshorane to form intermediate B; (iii) nucleophilic
4519
M. Salim et al. / Tetrahedron Letters 52 (2011) 4518–4520 Table 1 Synthesis of oxa[9]helicene derivatives Entry
Substrate
Product
1 2
O
A B
87 72
A B
74 65
A B
42 34
A B
32 71
A B
38 59
A B
63 32
3a
3 4
Me Me
O
O
O
Me 3b
Me 2b 5 6
Et Et
O
O
O
Et 3c
Et 2c 7 8
t
Bu t
O
Bu
O
O t Bu 2d
t Bu 3d
9 10
O O
O
2e
3e
Br
Br
O Br
Yield (%)
O
O 2a
11 12
Method
O
Br
O 2f
3f
Method A: Lawesson’s reagent (2.0 equiv), toluene, reflux, 15–20 h. Method B: P4S10 (2.0 equiv), toluene, reflux, 2–5 h.
R 2
R
R
CuCl(OH)-TMEDA
1
R
O
air, CHCl3
OH
2 1
Lawesson's reagent or P4S10
R O
O 2
R 1
R
1
R
2
R
2
2
R
1
1
3
Scheme 1.
substitution by S-phosphonodithionate is caused the formation of 3 and C; (iv) the produced C is decomposed to form thiaphosphirane 3-sulfide (D) and dithioxophoshorane. This reaction mechanism is analogous to that proposed mechanism for the reaction of N-alkylhydroxamic acid with Lawesson’s reagent.11
In summary, we have demonstrated a novel and efficient reductive cyclization of helical quinone mediated by LR or P4S10 that produces oxa[9]helicenes. We can also characterize the molecular structure and spectroscopic properties by several analytical methods. Further studies on the synthesis of novel helical molecules are in progress in our laboratories.
4520
M. Salim et al. / Tetrahedron Letters 52 (2011) 4518–4520
S
SS
P
H 3 CO
P S S
OCH3
2
H 3 CO
P S
Lawesson's reagent S SS P
S S
P
P S
S
S
S
P
2
S
S
P
S P S
S
S P4S10
O O 2
S O
R P S
S
S
O
S
H
H
S P
S P
O
R
A
R P
P
O
S
B
S R
P S
S
O
O 3
R
S
R LR: R=CH3 OC 6H 4, P4S10: R=S2PS-
R P
S S S
S C
S
R P
O
+
R P S
S R P S O D
Scheme 2. Plausible mechanism.
Acknowledgment We thank Mr. M. Roppongi for the MS spectra (Collaboration Center for Research Development, Utsunomiya University). References and notes
5.
6. 7.
1. Kawasaki, T.; Suzuki, K.; Licandro, E.; Bossi, A.; Maiorana, S.; Soai, K. Tetrahedron: Asymmetry 2006, 17, 2050; (b) Takenaka, N.; Sarangthem, R. S.; Captain, B. Angew. Chem., Int. Ed. 2008, 47, 9708; (c) Sato, I.; Yamashima, R.; Kadowaki, K.; Yamamoto, J.; Shibata, T.; Soai, K. Angew. Chem., Int. Ed. 2001, 40, 1096; (d) Reetz, M. T.; Beuttenmüller, E. W.; Goddard, R. Tetrahedron Lett. 1997, 38, 3211; (e) Reetz, M. T.; Sostmann, S. J. Organomet. Chem. 2000, 603, 105; (f) Dreher, S. D.; Katz, T. J.; Lam, K.-C.; Rheingold, A. L. J. Org. Chem. 2000, 65, 815. 2. For a recent review on chiral recognition in helicenes, see: (a) Amemiya, R.; Yamaguchi, M. Org. Biomol. Chem. 2008, 6, 26; (b) Yamaguchi, M. J. Synthetic Org. Chem. 2011, 69, 17. 3. (a) Chen, C.-T.; Chou, Y.-C. J. Am. Chem. Soc. 2000, 122, 7662; (b) Ashitaka, H.; Yokoh, Y.; Shimizu, R.; Yokozawa, T.; Morita, K.; Suehiro, T.; Matsumoto, Y. Nonlinear Opt. 1993, 4, 281; (c) Lovinger, A. J.; Nuckolls, C.; Katz, T. J. J. Am. Chem. Soc. 1998, 120, 264. 4. (a) Bossi, A.; Falciola, L.; Graiff, C.; Maiorana, S.; Rigamonti, C.; Tiripicchio, A.; Licandro, E.; Mussini, P. R. Electrochim. Acta 2009, 54, 5083; (b) Kitahara, Y.; Tanaka, K. Chem. Commun. 2002, 932; (c) Torras, J.; Bertran, O.; Alemán, C. J. Phys. Chem. B 2009, 113, 15196; (d) Tian, Y.-H.; Park, G.; Kertesz, M. Chem. Mater. 2008, 20, 3267; (e) Okuyama, T.; Tani, Y.; Miyake, K.; Yokoyama, Y. J. Org.
8.
9. 10. 11.
Chem. 2007, 72, 1634; (f) Cpllins, S. K.; Vachon, M. P. Org. Biomol. Chem. 2006, 4, 2518. (a) Pieters, G.; Gaucher, A.; Marque, S.; Maurel, F.; Lesot, P.; Prim, D. J. Org. Chem. 2010, 75, 2096; (b) Spencer, D. D.; Daniel, J. W.; Katz, T. J. J. Org. Chem. 1999, 64, 3671; (c) Areephong, J.; Ruangsupapichart, N.; Thongpanchang, T. Tetrahedron Lett. 2004, 45, 3067. Karikomi, M.; Yamada, M.; Ogawa, Y.; Houjou, H.; Seki, K.; Hiratani, K.; Haga, K.; Uyehara, T. Tetrahedron Lett. 2005, 46, 5867. Typical procedure (method A): A solution of helical quinone 2 (48 mg, 0.10 mmol) and Lawesson’s reagent (41 mg, 0.10 mmol, 2 equiv) was refluxed for 20 h in toluene. The mixture was concentrated then separated by column chromatography on silicagel eluted by chloroform. 3a was obtained 41 mg (87% yield). (method B): A solution of helical quinone 2 (48 mg, 0.10 mmol) and phosphorus pentasulfide (P4S10) (22 mg, 0.050 mmol, 2 equiv) was refluxed for 5 h in toluene. The mixture was concentrated then purified by column chromatography on silicagel and eluted by chloroform. 34 mg of 3a was obtained (72% yield). Compound characterization: 3a: mp 310–314 °C; 1H NMR (CDCl3, 500 MHz) d: 5.72 (2H, t, J = 7.5 Hz), 6.19 (2H, d, J = 8.5 Hz), 6.76 (2H, t, J = 7.3 Hz), 7.31 (2H, d, J = 8.0 Hz), 7.37 (2H, d, J = 8.5 Hz), 7.57 (2H, d, J = 8.5 Hz,), 7.60 (2H, d, J = 8.5 Hz), 8.11 (2H, d, J = 8.5 Hz), 8.27 (2H, d, J = 8.5 Hz), 8.31 (2H, d, J = 8.0 Hz). 13C NMR (CDCl3, 100 MHz): 110.95, 121.02, 122.19, 124.03, 124.33, 124.62, 125.15, 125.34, 126.20, 126.27, 126.50, 126.93, 127.29, 127.61, 129.45, 129.51, 129.94, 154.22; HRMS (EI) calculated for C36H20O [M]+: 468.1514, found 468.1504. Ozturk, T.; Ertas, E.; Mert, O. Chem. Rev. 2010, 110, 3419. Ozturk, T.; Ertas, E.; Mert, O. Chem. Rev. 2007, 107, 5210. Przychodzen´, W. Eur. J. Org. Chem. 2005, 2002.