Pd/C Catalyzed Oxidative Aminocarbonylation of Aryldiazonium Tetrafluoroborate Salts Through sp3C-N Bond Activation of Inert Tertiary Amines to Tertiary Amides.

Abstract

Aryldiazonium tetrafluoroborate salts are highly accessible from readily available and inexpensive amines, and by realizing these advantages, we have developed an efficient protocol, that employs aryldiazonium tetrafluoroborate salts as an effective electrophile for oxidative aminocarbonylation with unreactive tertiary amines. In this, molecular oxygen has been used as an ideal and green oxidant which activates the inert C-N bond. We prepared various derivatives of aryldiazonium tetrafluoroborate salts which includes different electron withdrawing and electron donating group substituents. This protocol utilizes Pd/C as a heterogeneous catalyst which is smoothly recyclable. Moreover, this developed method is ligand and co-catalyst free and it does not require any base to activate the amines as nucleophile, and the new process effectively provides a mild pathway toward a variety of tertiary amide moieties with significant yield. This way, the potent protocol is economical, simple, recyclable and operates at milder conditions and contributes towards valuable products that are vital in an industrial domain.