Additions of functionalized α-substituted allylboronates to aldehydes under the novel Lewis and Brønsted acid catalyzed manifolds
作者:Lisa Carosi、Hugo Lachance、Dennis G. Hall
DOI:10.1016/j.tetlet.2005.10.115
日期:2005.12
stereo- and chemoselectivity in the additions of four model α-substituted allylboronates to benzaldehyde was examined under the standard thermal (uncatalyzed) conditions and the novel Lewis and Brønsted acid-catalyzed conditions. With either of Sc(OTf)3 or triflic acid as catalysts, an α-ethyl allylboronate, 1a, led to a surprising inversion of stereoselectivity that can be tentatively rationalized through