Synthesis of bulky aryl group-substituted chiral bis(guanidino) iminophosphoranes as uncharged chiral organosuperbase catalysts

Australian Journal of Chemistry

Volumn 67, Issue 7, 2014, Pages 1124-1128

  Takeda, Tadahiro ^a   Terada, Masahiro ^b  

^a DAIICHI SANKYO CO   (Japan)

^b TOHOKU UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

SUBSTITUTION REACTIONS;

ARYL GROUP; ARYL SUBSTITUENTS; CHEMICAL YIELDS; ENANTIOSELECTIVE; IMINOPHOSPHORANES; SYNTHETIC PROCEDURES;

CATALYSTS;

EID: 84904440377     PISSN: 00049425     EISSN: 14450038     Source Type: Journal    
DOI: 10.1071/CH14195     Document Type: Article

References (27)

1. For reviews on organobase catalysis, see: C. Palomo, M. Oiarbide, R. López, Chem. Soc. Rev. 2009, 38, 632. doi:10.1039/B708453F
2. Superbases for Organic Synthesis (Ed. T. Ishikawa) 2009, Ch 4 (John Wiley & Sons: Chippenham, UK).
3. For reviews on chiral guanidine and P1-osphazene catalysis, see: (a) T. Ishikawa, T. Kumamoto, Synthesis 2006, 737. doi:10.1055/ S-2006-926325
4. D. Leow, C.-H. Tan, Chem. Asian J. 2009, 4, 488. doi:10.1002/ ASIA.200800361
5. Y. Sohtome, K. Nagasawa, Synlett 2010, 1.
6. D. Leow, C.-H. Tan, Synlett 2010, 1589.
7. M. J. Terada, Synth. Org. Chem. Jpn. 2010, 68, 1159. doi:10.5059/ YUKIGOSEIKYOKAISHI.68.1159
8. D. Uraguchi, T. Ooi, J. Synth. Org. Chem. Jpn. 2010, 68, 1185. doi:10.5059/YUKIGOSEIKYOKAISHI.68.1185
9. For other examples of chiral guanidines, P1-osphazenes, and other base catalysts, see: (a) R. Chinchilla, C. Nájera, P. Sánchez- Agulló, Tetrahedron: Asymmetry 1994, 5, 1393.
10. E. J. Corey, M. J. Grogan, Org. Lett. 1999, 1, 157. doi:10.1021/ OL990623L
11. S. Dong, X. Liu, X. Chen, F. Mei, Y. Zhang, B. Gao, L. Lin, X. Feng, J. Am. Chem. Soc. 2010, 132, 10560.
12. T. Misaki, K. Kawano, T. Sugimura, J. Am. Chem. Soc. 2011, 133, 5695. doi:10.1021/JA200283N
13. Y. Yang, S. Dong, X. Liu, L. Lin, X. Feng, Chem. Commun. 2012, 5040. doi:10.1039/C2CC31470C
14. J. S. Bandar, T. H. Lambert, J. Am. Chem. Soc. 2012, 134, 5552. doi:10.1021/JA3015764
15. D. Uraguchi, K. Yoshida, Y. Ueki, T. Ooi, J. Am. Chem. Soc. 2012, 134, 19370. doi:10.1021/JA310209G
16. L. Wu, G. Li, Q. Fu, L. Yu, Z. Tang, Org. Biomol. Chem. 2013, 11, 443. doi:10.1039/C2OB26950C
17. Q. Dai, H. Huang, J. C.-G Zhao, J. Org. Chem. 2013, 78, 4153. doi:10.1021/JO4001806
18. L. Zou, B. Wang, H. Mu, H. Zhang, Y. Song, J. Qu, Org. Lett. 2013, 15, 3106. doi:10.1021/OL401306H
19. D. Uraguchi, Y. Ueki, A. Sugiyama, T. Ooi, Chem. Sci. 2013, 4, 1308. doi:10.1039/C2SC22027J
20. S. Dong, X. Liu, Y. Zhu, P. He, L. Lin, X. Feng, J. Am. Chem. Soc. 2013, 135, 10026. doi:10.1021/JA404379N
21. T. Takeda, M. Terada, J. Am. Chem. Soc. 2013, 135, 15306. doi:10.1021/JA408296H
22. S. E. Pipko, L. V. Bezgubenko, A. D. Sinitsa, E. B. Rusanov, E. G. Kapustin, M. I. Povolotskii, V. V. Shvadchak, HeteroatomChem. 2008, 19, 171. doi:10.1002/HC.20392 (Pubitemid 351378712)
23. See Supplementary Material for details.
24. See Supplementary Material for details.
25. Both of isomers 1b-HBr dissolved well in toluene to give a clear solution even at low temperature. In contrast, the solubility of 1 (m) -1c-HBr in toluene was not good. A white suspension was formed even at elevated temperatures and this did not change in the presence of excess NaN(SiMe3)2.
26. CCDC 994562 ( 1 (m) -1a), CCDC 994431 ((P)-1a), and CCDC 994563 ((P)-1c) contain the supplementary crystallographic data for this paper. The data can be obtained free of charge from The Cambridge Crystallographic Data Centre (CCDC) via www.ccdc.cam.ac.uk/ data-request/cif (2014/March/31).
27. In order to confirm the conformational symmetry of 1 (m) -1a-HBr and 1 (p) -1a-HBr in solution, we conducted a low-temperature 1H NMR analysis of these salts. Significant broadening of N-H protons and protons at the benzylic position of DPEN was observed in 1 (p) -1a-HBr. In contrast, low-temperature NMR analysis of 1 (m) -1a-HBr exhibited no great change in the shape of peaks compared with that at room temperature. These observations strongly suggest that 1 (p) -1a-HBr possesses an unsymmetrical conformation (C1-symmetry) even in solution, although rapid conformational change would take place, whereas 1 (m) -1a-HBr possesses a C2-symmetric structure as observed in the crystalline state. See Supplementary Material for details.