Synthesis, characterization, and coordination chemistry of several novel electroneutral phosphane ligands

The reaction of fluorocarbon (Rf) reagents C2F5Li or C2F3Li with diaminochlorophosphanes (R2N)2PCl produced four new phosphane ligands of the type (R2N)2P(Rf). Addition of (Et2N)2PCl to ethereal solutions of C2F5Li or C2F3Li produced (Et2N)2PC2F51 and (Et2N)2PC2F32; treatment of (C4H4N)2PCl and (C4H8N)2PCl with C2F5Li afforded (C4H4N)2PC2F53 and (C4H8N)2PC2F54. All ligands were isolated as colorless, high-boiling liquids. Substitution reactions of 1–4 with Mo(CO)6 in a refluxing alkane solvent yielded complexes of the type (L)Mo(CO)5 (L = (Et2N)2PC2F5, 5; (Et2N)2PC2F36; (C4H4N)2PC2F57 and (C4H8N)2PC2F58) as colorless solids in low to moderate (25–62%) yields. Complexes 5, 7 and 8 were structurally characterized by single crystal X-ray diffraction. A comparison of IR stretching frequencies and X-ray bond length data suggests these ligands approximate the electronic influence of phosphites.