Bis(diphenylphosphino)methanedicopper(I) units bridged by dicarboxylates

Two novel compounds, [(mu -dppm)(2)Cu-2(O2CC6H4CO2)Cu-2(mu -dPPM)(2)](PF6)(2).3.4CH(2)Cl(2) (1 .3.4CH(2)Cl(2)) and [(mu -dppm)(2)Cu-2(O2CC2F4CO2)Cu-2(mu -dppm)(2)](PF6)(2). 5CH(2)Cl(2) (2-5CH(2)Cl(2)), have been prepared from the reactions of [(mu -dppm)(2)Cu-2(CH3CN)(2)](PF6)(2) with the corresponding dicarboxylate salts, and their structures have been determined crystallographically. The crystal structures of 1 and 2 consist of the complex cations [(mu -dppm)(2)Cu-2(L-L)Cu-2(mu -dppm)(2)](2+), in which two dppm-bridged dinuclear copper(I) units are linked by dicarboxylate bridges L-L2- (L-L = O2CC6H4CO2 and O2CC2F4CO2) in an end-to-end fashion, PF6- ions and dichloromethane molecules. The Cu . . . Cu separations within the [(mu -dppm)(2)Cu-2](2+) units are 2.707(1) and 2.833(1) Angstrom in 1 and 2, respectively, In both complexes, the copper(I) centers are in a trigonal coordination environment comprised by one O and two P atoms; additional contacts between the Cu. centers and chlorine atoms of dichloromethane are observed in 2. (C) 2001 Published by Elsevier Science B.V.