Ruthenium-Catalyzed Synthesis of 1,5-Dichlorides by Sequential Intermolecular Kharasch Reactions

Sequential intermolecular atom transfer radical addition reactions of activated dichlorides Cl2CRR′ (R = CN, CO2Et, R′ = H, CN, CO2Et) with two olefins catalyzed by [Cp*RuCl2(PPh3)] in the presence Mg allow the synthesis of linear 1,5-dichlorides. Different olefins can be employed in the first and in the second addition reaction. The reaction products are interesting synthetic precursors as demonstrated by the synthesis of two cyclopentanes by Mg-induced dechlorination. The structure of trans-3,4-diphenylcyclopentanecarbonitrile was determined by single-crystal X-ray diffraction.