Dp. Curran et Sb. Ko, SYNTHESIS OF OPTICALLY-ACTIVE ALPHA-HYDROXY LACTONES BY SHARPLESS ASYMMETRIC DIHYDROXYLATIONS OF KETENE ACETALS, ENOL ETHERS, AND ENE LACTONES, Journal of organic chemistry, 59(21), 1994, pp. 6139-6141
Three different AD routes to optically active alpha-hydroxy lactones o
f good to excellent optical purity are reported. The substrates for th
e AD reaction are endocyclic ketene acetals, endocyclic enol ethers, a
nd exocyclic alpha,beta-unsaturated lactones.