Benzoylformyl Complexes of Iron and Molybdenum

Benzoylformyl complexes CpMo(COCOPh)(CO) 3 (1) and CpFe(COCOPh)(CO) 2 (2) were prepared by the reactions of [CpMo(CO) 3 ] − and [CpFe(CO) 2 ] − ions with PhCOCOCl, respectively. The single‐crystal structure of complex 1 has been determined by X‐ray diffraction with crystal data: P2 1 /c, a = 6.674 (3) Å, b = 13.301 (4) Å, c= 16.903(6) Å, β = 90.82 (5)°,V = 1500(1) Å 3 , Z = 4. Least‐squares refinement on 894 reflections with I ≥ 2.0 σ(I) led to R = 0.041, R W = 0.042. Complex 1 contains a near perpendicular s ‐trans oxalyl moiety in the benzoylformyl ligand with the torsional angle O4‐C4‐C5‐O5 being 104 (1)°. The iron complex suffers spontaneous decarbonylation at 25 °C to yield CpFe(COPh)(CO) 2 .