Unprecedented copper-mediated oxidative demethylation of propionamides via bidentate-chelation assistance.

A copper-mediated directed demethylation of propionamides has been developed. This reaction proceeds predominantly at the α-methyl groups of aliphatic amides with high efficiency and provides a unique tool for the direct cleavage of unactivated C(sp(3))-C(sp(3)) bonds. The directing groups can be smoothly removed to afford the corresponding alkyl carboxylic acids.

Copper-catalyzed reductive cross-coupling of nonactivated alkyl tosylates and mesylates with alkyl and aryl bromides.

A copper-catalyzed reductive cross-coupling reaction of nonactivated alkyl tosylates and mesylates with alkyl and aryl bromides was developed. It provides a practical method for efficient and cost-effective construction of aryl-alkyl and alkyl-alkyl CC bonds with stereocontrol from readily available substrates. When used in an intramolecular fashion, the reaction enables convenient access to various substituted carbo- or heterocycles, such as 2,3-dihydrobenzofuran and benzochromene derivatives.