Syntheses, Structures and Catalytic Activity of p-Phenylene-or p -Biphenylene-Bridged Biscyclopentadienyl Dinuclear Rhenium Carbonyl Complexes

Thermal treatment of two p -phenylene-and p -Biphenylene-bridged biscyclopentadienes (C 5 Me 4 H)E(C 5 Me 4 H) (E=C 6 H 4 , (C 6 H 4 ) 2 ) with Re 2 (CO) 10 in refluxing mesitylene gave the corresponding complexes (E)[( η 5 -C 5 Me 4 )Re(CO) 3 ] 2 (E=C 6 H 4 ( 1 ), (C 6 H 4 ) 2 ( 2 )), which were separated by chromatography, and characterized by elemental analysis, IR, 1 H NMR and 13 C NMR spectroscopy. The molecular structures of complexes 1 and 2 were characterized by X-ray crystal diffraction analysis, showing both them are monobridged biscyclopentadienyl dinuclear rhenium carbonyl complexes. In addition, the catalytic performance of complexes 1 and 2 was also tested, and it was found that both complexes were obviously active for Friedel-Crafts acylation reactions.