Selective Formation of Adjacent Stereocenters by Allylboration of Ketones under Mild Neutral Conditions
journal contributionposted on 16.12.2015, 22:51 by Rauful Alam, Mihai, Raducan, Lars Eriksson, Kálmán J. Szabó
Allylboronic acids readily react with a broad variety of ketones, affording homoallylic alcohols with adjacent quaternary and tertiary stereocenters. The reaction proceeds with very high anti stereoselectivity even if the substituents of the keto group have a similar size. α-Keto acids react with syn stereoselectivity probably due to the formation of acyl boronate intermediates. The allylation reactions proceed without added acids/bases under mild conditions. Because of this, many functionalities are tolerated even with in situ generated allylboronic acids.