Attachment of carbonyl functionalities onto olefins via copper-promoted radical reaction of dichloromethylcyanides

Chemo- and regioselective protocols for attachment of various carbonyl functionalities onto unactivated olefins have been developed. Atom transfer radical reactions of Cl3CCN, Cl2C(R)CN, and Cl2C(CN)2 were all promoted efficiently by a catalytic amount of CuCl and 1,1′-bis(diphenylphosphino)ferrocene to introduce chloromethylcyanide and chloride units to the C–C double bonds. Conversion of the chloromethylcyanide to the carbonyl functionalities (e.g., aldehydes, ketones and esters), and subsequent double bond reconstruction through elimination of HCl resulted in selective formation of the carbonyl-conjugated E-olefins.