LAUSR

Abstract A new family of benzimdazolin-2-iminato actinide−(IV) complexes [(Bim 7-Me Dipp/Me N)An(N(SiMe 3 ) 2 ) 3 ] (An = U ( 3 ), Th ( 4 )) and [(Bim 4-Me Dipp/Me N)An(N(SiMe 3 ) 2 ) 3 ] (An = U ( 5 ), Th ( 6 )) were synthesized and their solid state structures were established by single-crystal X-ray diffraction analysis. The catalytic performances of complexes 3 – 6 towards the homo- and cross-coupling of aldehydes (Tishchenko reaction) were studied and the thorium complexes 4 and 6 displayed moderate to high activities for the production of the corresponding symmetric and unsymmetrical esters. Coupling of aldehyde and alcohols, known as the tandem proton-transfer esterification, and the intermolecular coupling reaction between aldehyde and trifluoromethylketones were also investigated by these thorium complexes, indicating a complementary method to obtain unsymmetrical esters selectively. Plausible mechanisms for these reactions are proposed based on stoichiometric studies.