Synthesis and structural characterization of a phosphido-bridged heterobimetallic transition metal complex, (CO)3Fe(μ-PPh2)2Mo(CO)4

Article abstract of DOI:10.1016/0022-328X(96)06255-9

A heterobimetallic transition metal complex (CO)₃Fe(μ-PPh₂)₂Mo(CO)₄ (2) has been synthesized by the direct reaction of trans-(CO)₃Fe(Ph₂PH)₂ (1) with Mo(CO)₆ in benzene, and fully characterized by single-crystal X-ray analysis. Complex 2 crystallizes in the space group C2 (No. 5) with a = 20.688(4), b = 8.809(2), c = 17.081(3) A, β = 102.60(3)°, V = 3038(2) A³ and Z = 4. The structure has been refined to R_F = 0.032 and R_wF = 0.041 for 2579 Mo K α reflections with F > 4σ(F). The two metal carbonyl fragments are bridged by a pair of μ-PPh₂ ligands. Although the Fe-Mo distance of 2.854(1) A in 2 is much longer than the sum of the metallic radii of Fe and Mo atoms [2.66 A], the existence of metal-metal bonding between the Fe and Mo atoms has been deduced from spectroscopic and structural data.