Nickel‐Catalyzed Coupling of Thiomethyl‐Substituted 1,3‐Benzothiazoles with Secondary Alkyl Grignard Reagents

Abstract

Transition-metal catalyzed CC bond-forming reaction is a useful and straightforward method for the functionalization of azole heterocycles, [1] which are frequently found as key frameworks in natural products, pharmaceutics, and organic functional materials. [2a] Because the C2 position of 1,3azoles, such as oxazoles, thiazoles, and imidazoles, in many natural and synthetic compounds are alkylated, [2b–g] the development of simple and efficient methods for introducing an alkyl group in this position would be highly desirable for the synthesis of these compounds. The conventional reaction for the alkylation of 1,3-azoles includes the coupling of 2metalated azoles generated beforehand or in situ from the parent unsubstituted 1,3-azole under basic conditions with alkyl electrophiles (Scheme 1, path A) [3, 4] and the coupling