Mimicking hydrogen-atom-transfer-like reactivity in copper-catalysed olefin hydrofunctionalization

Abstract

The renaissance of catalytic metal hydride hydrogen atom transfer (MHAT) offers advanced tools for radical chemistry on simple olefins. While 3d transition metals like cobalt, iron and manganese have been extensively studied in catalytic MHAT, the potential of copper remains unexplored. This is due to the polar reactivity exhibited by classical nucleophilic Cu(I)–H. Here we report copper-catalysed MHAT-like oxidative hydrofunctionalization reactions. In contrast to conventional Cu(I)–H chemistry, the putative Cu-MHAT process produces alkyl radicals with high chemoselectivity and regioselectivity, which are subsequently captured by Cu(II) species to undergo coupling reactions with a broad scope of oxygen-, nitrogen-, halogen- and carbon-based nucleophiles. Preliminary results suggest viable extension to asymmetric catalysis and radical polymerization. This work offers a complementary oxidative MHAT platform. Cobalt, iron or manganese catalysts are the metals of choice in alkene functionalization reactions via catalytic metal hydride hydrogen atom transfer (MHAT). Now a complementary MHAT-like system based on copper is proposed to operate in a regioselective Markovnikov addition reaction of nucleophiles to olefins.