Exploiting rhodium-catalysed ynamide hydroacylation as a platform for divergent heterocycle synthesis

Chem Sci. 2017 Dec 1;8(12):7963-7968. doi: 10.1039/c7sc03795c. Epub 2017 Oct 5.

Abstract

The first examples of ynamide hydroacylation are described. Using rhodium catalysis, linear β-enaminone products are generated in high yield and excellent regioselectivity from the combination of aldehydes and ynamides. The enaminone products are subsequently used as a platform to construct a diverse array of substituted pyrazoles, pyrimidines, and isoxazoles in a two-step, one-pot sequence. It was found that with judicious choice of catalyst system it was possible to overturn the regioselectivity of the hydroacylation reaction to generate α-enaminone products.