Cobalt-catalyzed regioselective hydrohydrazination of epoxides

Abstract

Using an air-stable cobalt catalyst [Cp*Co(1,2-Ph₂PC₆H₄S)(NCMe)]BF₄ (1, Cp* = Me₅C₅⁻), we have achieved catalytic regioselective hydrohydrazination of epoxides to 1,1-hydrazinoalcohols in an atom-economical manner. The catalysis involves a cobalt–hydrazine intermediate, in which the NH₂ group of the hydrazine binds to the metal center, inhibiting its nucleophilic reactivity and allowing the NH group to participate in the regioselective hydrohydrazination.