Organocatalytic Enantioselective [3+2] Cycloaddition of Azomethine Ylides and α,β‐Unsaturated Aldehydes

Abstract

One out of a possible 16: Commercially available α,α-diphenylprolinol catalyzes the [3+2] cycloaddition of α,β-unsaturated aldehydes with azomethine ylides derived from imines to produce pyrrolidines as single regioisomers with excellent diastereo- and enantioselectivities (see scheme; R1=aryl; R2=alkyl, aryl, 2-furyl). A fourth stereocenter can be introduced subsequently with complete stereoselectivity.