AAA in KAT/DYKAT processes: First- and second-generation asymmetric syntheses of (+)- and (-)-cyclophellitol

Kinetic resolutions and kinetic asymmetric transformations (KAT) as well as dynamic kinetic resolutions and dynamic kinetic asymmetric transformations (DYKAT) are important synthetic protocols. The feasibility of KAT and DYKA T processes for asymmetric allylic alkylations (AAA) is explored utilizing a single substrate - conduritol B tetraesters. Both processes can be perfor med resulting in excellent enantioselectivity The impact of nucleophile and leaving group on the effectiveness of each is outlined. The ability to dif ferentiate the various hydroxyl groups is also described. For this purpose, 4-tert-butyldimethylsiloxy-2.,2-dimethylbutyric acid was developed as a nu cleophile. The utility of effecting KAT/DYKAT processes through the, Pd-cat alyzed AAA reaction is demonstrated by efficient syntheses of both enantiom ers of the potent glycosidase inhibitor cyclophellitol.