title: A mild protocol for allylation and highly diastereoselective syn or anti crotylation of aldehydes in biphasic and aqueous media utilizing potassium allyl- and crotyltrifluoroborates.
abstract: [formula: see text] Potassium allyl- and crotyltrifluoroborates undergo addition to aldehydes in biphasic media as well as water to provide the corresponding homoallylic alcohols in high yields (> or = 94%), excellent diastereoselectivity (dr > or = 98:2), and without the necessity of any subsequent purification. The presence of a phase transfer catalyst (e.g., nBu4NI) significantly accelerates the rate of reaction, whereas added fluoride ion retards the reaction.
authors.affiliation: Department of Chemistry, University of Toronto, Toronto, ON, Canada M5S 3H6.
authors.forename: Avinash N
authors.initials: AN
authors.lastname: Thadani
authors.forename: Robert A
authors.initials: RA
authors.lastname: Batey