Nickel‐ and Cobalt‐Catalyzed Direct Alkylation of Azoles with N‐Tosylhydrazones Bearing Unactivated Alkyl Groups

Abstract

A matter of catalyst: Azole compounds can be directly alkylated with N-tosylhydrazones that bear unactivated alkyl groups (see scheme; phen=1,10-phenanthroline, Ts=p-toluenesulfonyl). Nickel catalysis enables the introduction of simple secondary alkyl chains into benzoxazole compounds, whereas the alkylation of 5-aryloxazoles and benzothiazole is possible by using a cobalt catalyst.