allo-Threonine-derived oxazaborolidinone (10 mol %) catalyzes the Friedel−Craftsalkylation of furans and indoles with simple acyclic α,β-unsaturated ketones to give products with high yield and high enantioselectivity. The use of N,N-dimethylaniline (2.5−10 mol %) as an additive is essential for enantioselectivity.
allo-Threonine-derived oxazaborolidinone (OXB) catalyzes the Friedel-Craftsalkylation of furans and indoles with simple acyclic α,β-unsaturated ketones to give the products in high yields and with high enantioselectivities. With 5-10 mol% of the OXB catalyst, enantioselectivities of up to 94% ee could be achieved for a variety of substrates. The use of N,N-dimethylaniline (2.5-10 mol%) as an additive