Crystal and molecular structures of dicarbonyldichlorobis(diphenylarsino)methanemolybdenum(II) and dicarbonyldichlorobis(diphenylphosphino)methanemolybdenum(II)–benzene (1/0.75)

Abstract

Crystals of [MoCl₂(CO)₂(dpam)₂][dpam = bis(diphenylarsino)methane](I) are orthorhombic, a= 11.134(5), b= 22.715(5), c= 19.138(6)Å, Z= 4, space group P2₁2₁2₁. Crystals of [MoCl₂(CO)₂(dppm)₂][dppm = bis-(diphenylphosphino)methane](II) are monoclinic, a= 19.863(18), b= 13.972(6), c= 19.064(13)Å, β= 101.30(11)°, Z= 4, space group P2₁/n. 1 974 (I) and 2 623 (II) independent reflections were measured by counter methods and refined by least squares to R 0.068 and 0.108. The structure of (I) is a relatively undistorted capped octahedron with a carbonyl group in the capping position [1.73(4)Å], a carbonyl group and two arsenic atoms in the capped face [1.83(4); 2.624(4), 2.596(4)Å], and one arsenic and two chlorine atoms in the uncapped face [2.681(4) 2.520(8), 2.501(8)Å], The geometry of (II) is similar but more distorted with bond lengths: Mo–C 1.91(2), 1.82(3) Mo–P 2.547(6), 2.487(7), 2.593(6), and Mo–Cl 2.554(6), 2.484(6)Å.