Permanganate oxidation of α,β-unsaturated carbonyls to vicinal tricarbonyls

Abstract

Vicinal tricarbonyl compounds (VTCs) are useful synthetic intermediates. Most synthetic methods of VTCs require toxic oxidants under cryogenic conditions or noble transition metal catalysis. In this paper, we report an...

Asymmetric permanganate dihydroxylation of enoates: substrate scope, mechanistic insights and application in bicalutamide synthesis

“…Cyclic manganate(V) diester is the common intermediate for permanganate oxidation of alkenes. In the presence of an acid additive, transformation of the cyclic manganate(V) diester intermediate is fast; oxohydroxylation products are formed when R 3 = H; 20,21 and vicinal tricarbonyl compounds are formed when R 1 = R 3 = H. 26 In the absence of an acid additive, hydrolysis of the cyclic manganate (V) diester intermediate to diols is a slow pathway. Dihydroxylated products are formed together with overoxidation byproducts (Fig.…”

“…This is the same as in permanganate oxidation of α,β-unsaturated carbonyls to vicinal tricarbonyl compounds. 26 Based on the observations in the study, a catalytic cycle is proposed in Fig. 2a.…”