Synthesis of some new 2-substituted 4,5-dihydroxypiperidines via Sharpless asymmetric dihydroxylation

摘要

Synthesis of seven new 2-substituted 4,5-dihydroxy piperidines have been reported using homoallylic carbamates as the starting material that have been synthesized via three-component reaction of aldehyde, allyl trimethyl silane and benzyl carbamate in presence of iodine as catalyst. Further N-allylation of the substrate followed by ring closing metathesis produced the corresponding 1,2,3,6-tetrahydropyridine derivatives. Subsequent Sharpless dihydroxylation of the tetrahydropyridines produced the 2-substituted 4,5-dihydroxy piperidines in high yield.