N-alkyl-N-vinylbenzylnorephedrines and their copolymers as chiral ligands for the highly enantioselective ethylation of N-diphenylphosphinylimine

Tetrahedron Asymmetry

Volumn 7, Issue 9, 1996, Pages 2519-2522

  Suzuki, Takefumi ^a   Narisada, Naoyuki ^a   Shibata, Takanori ^a   Soai, Kenso ^a  

^a TOKYO UNIVERSITY OF SCIENCE   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

COPOLYMER; IMINE; LIGAND; NOREPHEDRINE;

ALKYLATION; ARTICLE; CHEMICAL MODIFICATION; CHEMICAL REACTION; CHIRALITY; PRIORITY JOURNAL; REACTION ANALYSIS; STEREOCHEMISTRY;

EID: 0030249734     PISSN: 09574166     EISSN: None     Source Type: Journal    
DOI: 10.1016/0957-4166(96)00322-9     Document Type: Article

References (16)

1. 1. (a) K. Tomioka, I. Inoue, M. Shindo and K. Koga, Tetrahedron Lett., 1991, 32, 3095; K. Tomioka, I. Inoue, M. Shindo and K. Koga, Tetrahedron: Asymmetry, 1993, 4, 1603; S. E. Denmark, N. Nakajima and O. J.-C. Nicaise, J. Am. Chem. Soc., 1994, 116, 8797; I. Inoue, M. Shindo, K. Koga and K. Tomioka, Tetrahedron, 1994, 50, 4429.
2. 1. (a) K. Tomioka, I. Inoue, M. Shindo and K. Koga, Tetrahedron Lett., 1991, 32, 3095; K. Tomioka, I. Inoue, M. Shindo and K. Koga, Tetrahedron: Asymmetry, 1993, 4, 1603; S. E. Denmark, N. Nakajima and O. J.-C. Nicaise, J. Am. Chem. Soc., 1994, 116, 8797; I. Inoue, M. Shindo, K. Koga and K. Tomioka, Tetrahedron, 1994, 50, 4429.
3. 1. (a) K. Tomioka, I. Inoue, M. Shindo and K. Koga, Tetrahedron Lett., 1991, 32, 3095; K. Tomioka, I. Inoue, M. Shindo and K. Koga, Tetrahedron: Asymmetry, 1993, 4, 1603; S. E. Denmark, N. Nakajima and O. J.-C. Nicaise, J. Am. Chem. Soc., 1994, 116, 8797; I. Inoue, M. Shindo, K. Koga and K. Tomioka, Tetrahedron, 1994, 50, 4429.
4. 1. (a) K. Tomioka, I. Inoue, M. Shindo and K. Koga, Tetrahedron Lett., 1991, 32, 3095; K. Tomioka, I. Inoue, M. Shindo and K. Koga, Tetrahedron: Asymmetry, 1993, 4, 1603; S. E. Denmark, N. Nakajima and O. J.-C. Nicaise, J. Am. Chem. Soc., 1994, 116, 8797; I. Inoue, M. Shindo, K. Koga and K. Tomioka, Tetrahedron, 1994, 50, 4429.
5. (b) S. Itsuno, H. Yanaka, C. Hachisuka and K. Ito, J. Chem. Soc., Perkin Trans. 1, 1991, 3095;
6. (c) A. R. Katritzky and P. A. Harris, Tetrahedron: Asymmetry, 1992, 3, 437.
7. 2. K. Soai, T. Hatanaka and T. Miyazawa, J. Chem. Soc., Chem. Commun., 1992, 1097.
8. 3. K. Soai, T. Suzuki and T. Shono, J. Chem. Soc., Chem. Commun , 1994, 317; S. Itsuno, M. Sasaki, S. Kuroda and K. Ito, Tetrahedron: Asymmetry, 1995, 6, 1507.
9. 3. K. Soai, T. Suzuki and T. Shono, J. Chem. Soc., Chem. Commun , 1994, 317; S. Itsuno, M. Sasaki, S. Kuroda and K. Ito, Tetrahedron: Asymmetry, 1995, 6, 1507.
10. 4. K. Soai, S. Niwa and M. Watanabe, J. Chem. Soc., Perkin Trans. 1, 1989, 109.
11. 5. M. Watanabe and K. Soai, J. Chem. Soc., Perkin Trans. 1, 1994, 837.
12. 6. cf. Z. Zhengpu, P. Hodge and P. W. Stratford, Reactive Polymers, 1991, 15, 71.
13. 4 (2 mmol) and potassium carbonate (0.55g, 4 mmol) in EtOH (8 ml). The mixture was refluxed for 7 h, and EtOH was evaporated under reduced pressure. 10 ml of 2 M NaOH was added and the mixture was extracted with ether (10 ml × 5). The extract was dried over anhydrous sodium sulfate, evaporated, and purified with silica gel TLC (developing solvent hexane/acetone=3/1). Compounds 2a-d were obtained in 41-69%.
14. 8. W. B. Jennings and C. J. Lovely, Tetrahedron, 1991, 47, 5561.
15. 9. cf. S. Itsuno, Y. Sakurai, K. Ito, T. Maruyama, S. Nakahama and J. M. J. Fréchet, J. Org. Chem., 1990, 55, 304.
16. 6 styrene (1.46g, 14 mmol, 1.6 ml), DVB (0.52g, 4 mmol, 0.57 ml), α, α'-azobisisobutyronitrile (AIBN, 0.065g, 0.4 mmol), benzene (6 ml) and THF (6 ml). The mixture was stirred at 0 °C for 1h and then at 75 °C for 30 h. The reaction mixture was filtered, washed successively with water, MeOH, THF-MeOH, THF and MeOH (50 ml each). The polymer was dried at 40 °C in vacuo for 5 h. (1R, 2S)-3b (2.05g) was obtained. Elemental analysis of 3b: C 88.32%, H 7.43%, N 1.20%. Therefore the content of the nitrogen atom of (1R, 25)-3b was 0.899 mmol/g.