Simple and General Procedure for the Synthesis of α,β-Alkynyl Ketones from Nitriles Using Alkynyldimethylaluminum Reagents

Abstract

A simple and efficient approach for the synthesis of α,β-alkynyl ketones from nitriles and alkynyldimethylaluminum reagents, derived from trimethylaluminum and alkynes, is described. This methodology provides access to a wide range of α,β-alkynyl ketones with aliphatic, aromatic, and heteroaromatic substituents in moderate to high yield (53–90%). In the cases of aryl-substituted nitriles, the product can also be obtained as α,β-alkynyl N-H ket­imines in high yield (88–93%).

Key words

α,β-alkynyl ketones - α,β-alkynyl N-H ketimines - ­alkynes - trimethylaluminum - nitriles

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