Crystal structures of phosphine-supported (η(5)-cyclo­penta­dien­yl)molybdenum(II) propionyl complexes

Three cyclo­penta­dienylmolybdenum(II) propionyl complexes featuring tri­aryl­phosphine ligands with different para substituents, namely, dicarbon­yl(η(5)-cyclo­penta­dien­yl)propion­yl(tri­phenyl­phosphane-κP)molybdenum(II), [Mo(C(5)H(5))(C(3)H(5)O)(C(18)H(15)P)(CO)(2)], (1), dicarbon­yl(η(5)-cyclo­penta­dien­yl)propion­yl[tris­(4-fluoro­phen­yl)phosphane-κP]molybdenum(II), [Mo(C(5)H(5))(C(3)H(5)O)(C(18)H(12)F(3)P)(CO)(2)], (2), and dicarbon­yl(η(5)-cyclo­penta­dien­yl)propion­yl[tris­(4-meth­oxy­phen­yl)phosphane-κP]molybdenum(II) dichloromethane solvate, [Mo(C(5)H(5))(C(3)H(5)O)(C(21)H(21)O(3)P)(CO)(2)]·CH(2)Cl(2), (3), have been prepared from the corresponding ethyl complexes via phosphine-induced migratory insertion. These complexes exhibit four-legged piano-stool geom­etries with mol­ecular structures quite similar to each other and to related acetyl complexes. The extended structures of the three complexes differ somewhat, with the para substituent of the tri­aryl­phosphine of (2) (fluoro) or (3) (meth­oxy) engaging in non-classical C—H⋯F or C—H⋯O hydrogen-bonding inter­actions. The structure of (3) exhibits modest disorder in the position of one Cl atom of the di­chloro­methane solvent, which was modeled with two sites showing approximately equivalent occupancies [0.532 (15) and 0.478 (15)].