Electronic effects of aryl-substituted bis(oxazoline) ligands on the outcome of asymmetric copper-catalysed C-H insertion and aromatic addition reactions

The effect of the modification of bis(oxazoline) ligands on the outcome of copper-catalysed C-H insertion and aromatic addition reactions is described. In general, these reactions display minimum sensitivity in terms of enantiocontrol to variation of the electronic properties of the aryl moiety of the ligand however, some influence is observed for C-H insertions employing naphthyl-substituted bis(oxazolines) and for aromatic addition reactions of biphenyl diazo ketone substrates. The synthesis of the modified bis(oxazolines), which include four novel structures, is also described. (C) 2013 Elsevier Ltd. All rights reserved.