A Direct Aldol Addition of Simple Thioesters Employing Soft Enolization

Abstract

Simple thioesters undergo direct aldol addition to aldehydes in the presence of magnesium bromide-diethyl ether and N,N-diisopropylethylamine using untreated, reagent grade dichloromethane under atmospheric conditions. The reactions proceed extremely rapidly and in excellent yield.

direct aldol reaction - ester - magnesium - thioester - thiol

References

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<A NAME="RZ18206SS-5">5</A>

All thioesters used in this work, with the exception of commercially available 7, 10, and 11, were prepared via acylation of the corresponding commercially available thiols.

<A NAME="RZ18206SS-6">6</A>

Aldrich ACS reagent grade, ≥99.5%.