Chiral synthesis via organoboranes. 38. Selective reductions. 48. Asymmetric reduction of trifluoromethyl ketones by B-chlorodiisopinocampheylborane in high …
PV Ramachandran, AV Teodorovic, HC Brown
文献索引:Ramachandran, P. Veeraraghavan; Teodorovic, Aleksandar V.; Brown, Herbert C. Tetrahedron, 1993 , vol. 49, # 9 p. 1725 - 1738
(−)-B-Chlorodiisopinocampheylborane [(−)-DIP-ChlorideTM, 1], introduced by us several years ago, has been shown to reduce prochiral aryl and alkyl perfluorinated ketones to the corresponding optically active alcohols in very high ee. For example, 2, 2, 2- trifluoroacetophenone, trifluoroacetyl-1-naphthalene, and trifluoroacetyl-2-naphthalene are all reduced with 1 within 1–3 d at rt in 90% ee, 78% ee and 91% ee, respectively. The ...