Asymmetric organocatalytic domino Michael/aldol reactions: enantioselective synthesis of chiral cycloheptanones, tetrahydrochromenones, and polyfunctionalized bicyclo[3.2.1]octanes

Angew Chem Int Ed Engl. 2009;48(20):3699-702. doi: 10.1002/anie.200900754.

Abstract

C'mon 1,2-dione: A new diastereo- and enantioselective Lewis base catalyzed domino Michael/aldol reaction converts alpha,beta-unsaturated aldehydes and 1,2-diones into chiral bicyclo[3.2.1]octane-6-carbaldehydes. The products are produced in good to excellent enantioselectivities (90-98 % ee) and can be transformed into bicyclic diols and triols. Additionally, a retro-aldol cyclization provides access to valuable tetrahydrochromenones (see scheme).