Enantio- and Diastereoselective Organocatalytic α-Alkylation of Aldehydes with 3-Substituted 2-(Bromomethyl)acrylates

The catalytic direct α-alkylation of aldehydes
with 2-(bromomethyl)­acrylates
has been accomplished, giving rise to α-branched and functionalized
aldehydes of high diastereo- and enantiopurity. The influence of the
nature of the ester group of the acrylates in reaction stereoselectivity
and especially in reactivity is investigated. Optimum conditions implicate
the use of phenyl acrylates in conjunction with organocatalyst 8. Application of thus obtained adducts in synthesis is illustrated
with a concise stereocontrolled preparation of trisubstituted cyclopentenes.