ALDOL COUPLINGS OF CHIRAL FRAGMENTS WITH KINETIC RESOLUTION: SCOPE AND LIMITATIONS

Abstract

“The Thiopyran Route to Polypropionates” is a synthetic strategy that involves the stepwise aldol reactions of 6 and 7a to rapidly access stereochemically complex tetrapropionate 8 and hexapropionate synthons 72 or 73. Coupling racemic 7a with any of the four enantioenriched diastereomers 8 with kinetic resolution (KR) is possible with rational design of the reaction using the 'multiplicativity' rule. Thus, any of two of the eight possible aldol adducts, 72 or 73, are selectively available from the same reactants.