Cobalt-Catalyzed Monoselective ortho-C–H Ethylation of Carboxamides with Triethylaluminum

Published as part of the Special Topic Cobalt in Organic Synthesis

Abstract

A 1,10-phenanthroline ligated cobalt catalyst is reported for the ortho-C–H ethylation of aromatic, heteroaromatic, and alkenyl carboxamides with inexpensive triethylaluminum. This reaction represented the first example of cobalt-catalyzed monoselective direct ortho-C–H ethylation reaction with aluminum reagent as an alkyl donor.

Key words

cobalt - ethylation - monoselectivity - organoaluminum - C–H functionalization

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