| abstract |
Selective hydrogenation of the carbon-carbon double bonds of conjugated diene copolymers is effective homogeneous solution in an organic solvent in the presence of certain divalent ruthenium carbonyl complex catalysts. The ruthenium catalysts have the general formula: Ru(CO)HA(Z)3(1) wherein A is a halogen atom, most preferably chlorine, or a hydrogen atom and Z is -PR1R2R3 in which R1, R2 and R3 are the same or different and are selected from alkyl and aryl groups, preferably all the phenyl group, or have the general formula: Ru(CO)XY(Z)2(2) wherein X is a carboxylate group, particularly ClCH2COO-, Cl2CHCOO-, Cl3CCOO-, F3CCOO-, CH3COO-, C6H5COO- or p-ClC6H4COO-, Y is a halogen atom, preferably a chlorine atom or a bromine atom, or a hydrogen atom or a carboxylate group, Z is as defined above; or have the general formula: Ru T(CO)(NO)(Z)2(3) wherein T is a halogen atom, preferably a chlorine or bromine atom, and Z is as defined above; or have the general formula: Ru T(NO)(Z)2(4) wherein T and Z are as defined above; or have the general formula: Ru H(NO)(Z)3(5) wherein Z is as defined above; or have the general formula: Ru (NO)2(Z)2(6) wherein Z is as defined above. |