Direct, stereospecific generation of (Z)-disubstituted allylic alcohols.
A one-pot method to prepare highly functionalized (Z)-disubstituted allylic alcohols is introduced. Hydroboration of a variety of 1-bromo-1-acetylenes with dicyclohexyl borane, reaction with t-BuLi, and transmetalation to zinc generates a (Z)-disubstituted vinylzinc reagent. In situ reaction of this reagent with aldehydes generates (Z)-disubstituted allylic alcohols in high yields (81-97%). Addition to chiral protected alpha- or beta-oxygenated aldehydes proceeds with diastereoselectivities between 6:1 and 18:1. The anti-Felkin product is obtained in most cases.
Jeon
Sang-Jin
SJ
P. Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, USA.
Fisher
Ethan L
EL
Carroll
Patrick J
PJ
Walsh
Patrick J
PJ
D002384:Catalysis; D015394:Molecular Structure; D020005:Propanols / Q000138:chemical synthesis*
D020005:Propanols; C006463:allyl alcohol