An efficient N-heterocyclic carbene (NHC)-catalyzed direct thioesterification of aldehydes and α, β-unsaturated aldehydes (enals) with diaryl disulfides is reported. The protocol involves carbonyl umpolung reactivity of aldehydes and enals in which the carbonyl carbon attacks nucleophilically on diaryl disulfides to afford thioesters and α, β-unsaturated thioesters, respectively. However, aliphatic aldehydes are not suitable substrates for this ...