Stereochemistry of seven-co-ordinate complexes containing a tin–molybdenum bond: crystal structure of [1,2-bis(diphenylphosphino)- ethane]tetracarbonyl(trichlorostannyl)molybdenum(I) aquapentachloro-stannate–benzene

Abstract

Crystals of the title compound are monoclinic with a= 21.846(5), b= 12.346(3), c= 20.486(6)Å, β= 122.23(2)°, Z= 4, space group =P2₁/c. The structure was solved from 2 149 observed diffractometer intensities by the symbolic addition method and refined by least-squares methods to R 9.4%. The cation has monocapped octahedral geometry with the SnCl₃ group bonded to the central molybdenum atom in the unique capping position [Mo–Sn 2.729(4)Å]. Three carbonyl groups define the capped face, while the bidentate ligand and the remaining carbonyl group make up the uncapped face. The anion has the expected irregular octahedral geometry. The stereochemistry of the cation is compared with that of relevant seven-co-ordinate molecules containing Mo–Sn and W–Sn bonds.