ASYMMETRIC-SYNTHESIS USING REACTIONS WITH MODEST GROUP SELECTIVITY

The isomeric purity of products from certain group-selective reactions can be significantly amplified when reactions can occur sequentially. The theoretical basis for a strategy that exploits reactions with mod est enantiotopic group selectivity for asymmetric synthesis is describ ed. The relationships between conversion, yield, and isomeric purity f or such a process are calculated using a simple kinetic model. A simpl e method for selecting candidate group-selective reactions from known face-selective reactions is presented. Application of the strategy is illustrated with the reduction of D-glucose and D-galactose derived di aldehydes with B-isopinocampheyl-9-borabicyclo[3.3.1]nonane (Alpine-Bo rane(R)).