ASYMMETRIC ALDOL REACTIONS USING CHIRAL BORON REAGENTS: APPLICATION TO THE SYNTHESIS OF TIRANDAMYCIN A
The bicyclic acetal 1, a key intermediate in previous synthetic studies on tirandamycin A, has been prepared in enantiomerically pure form starting from the (R)-ethylketone 2 and the aldehyde 3.A reagent controlled aldol reaction using (-)-(Ipc)2BOTf sele