B-iso-2-(2-diethylaminoethyl)apopinocampheyl-9-borabicyclo-[3.3.1]nonyl hydride - An improved chiral reducing agent for straight chain aliphatic ketones

Tetrahedron Letters

Volumn 37, Issue 22, 1996, Pages 3791-3794

  Weissman, Steven A ^a,b   Ramachandran, P Veeraraghavan ^a  

^a PURDUE UNIVERSITY   (United States)

^b MERCK RESEARCH LABORATORIES   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

LITHIUM DERIVATIVE; REDUCING AGENT;

ARTICLE; CHEMICAL ANALYSIS; CHEMICAL REACTION; CHIRALITY; REDUCTION;

EID: 0029938452     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/0040-4039(96)00691-0     Document Type: Article

References (20)

1. Morrison, J. D., Ed. Asymmetric Synthesis; Academic: New York, 1983; Vol. 2, Chapters 2-4.
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3. (b) Brown, H. C.; Ramachandran, P. V. Acc. Chem. Res. 1992, 25, 16.
4. (c) Midland, M. M. Chem. Rev. 1989, 89, 1553.
5. For a review, see: Nogradi, M. Stereoselective Synthesis; VCH: New York, 1987; Chapter 3.
6. Noyori, R.; Tomino, I.; Yamada, M.; Nishizawa, M. J. Am. Chem. Soc. 1984, 106, 6717 and references cited therein.
7. Krishnamurthy, S.; Vogel, F.; Brown, H. C. J. Org. Chem. 1977, 42, 2534.
8. (a) Midland, M.; Kazubski, A. J. Org. Chem. 1982, 47, 2495.
9. (b) Midland, M. M.; Kazubski, A.; Woodling, R. E. J. Org. Chem. 1991, 56, 1068.
10. Imai, T.; Tamura, T.; Yaamura, A.; Sato, T.; Wollmann, T. A.; Kennedy, R. M.; Masamune, S. J. Am. Chem. Soc. 1986, 108, 7402.
11. (a) Brown, H. C.; Ramachandran, P. V. J. Org. Chem. 1989, 54, 4504.
12. (b) Ramachandran, P. V.; Brown, H. C.; Swaminathan, S. Tetrahedron: Asymmetry, 1990, 1, 433.
13. (c) Brown, H. C.; Ramachandran, P. V.; Weissman, S. A.; Swaminathan, S. J. Org. Chem., 1990, 55, 6328.
14. (d) Brown, H. C.; Ramachandran, P. V.; Teodorovic, A. V.; Swaminathan, S. Tetrahedron Lett. 1991, 32, 6691.
15. The pinene-based auxiliaries in reagents 2-4 were prepared from commercially available (-)-myrtenol (92% ee) as follows: myrtenyl methyl ether: with NaH and methyl iodide using the methodology described in ref. 7; myrtenyl amines: reaction of myrtenyl tosylate with the appropriate dialkylamine as noted in the Scheme of this manuscript.
16. 3).
17. Brown, H. C.; Joshi, N. N. J. Org. Chem. 1988, 53, 4059.
18. Bain, J. P. J. Am. Chem. Soc. 1946, 68, 638.
19. 3 and brine, and dried over magnesium sulfate. The volatiles were evaporated and the residue distilled to give 0.28 g of 2-octanol (71%). Capillary GC analysis (SPB™-5 column; 150 °C) of the Mosher ester indicates the presence of 88.5% (S)-isomer and 11.5% (R)-isomer (77% ee).
20. Approximate maximum solubility in THF/pentane at -78 °C.