Synthesis and Crystal Structures of Novel Group 6B Metal Carbonyl Complexes with N‐(4‐methyl‐2‐pyridinyl)‐P,P‐diphenylphosphinous Amide Ligand

The reaction of N ‐(4‐methyl‐2‐pyridinyl)‐ P,P ‐diphenylphosphinous amide ligand 4‐Me‐C 5 H 3 N‐2‐NH(PPh 2 ) ( 1 ) with M(CO) 6 (M=Cr, Mo, W) in refluxing toluene afforded a mononuclear group VIB metal tetracarbonyls [M(CO) 4 { 1 ‐κ 2 P,N }] (M=Cr( 2 ), Mo( 3 ), W( 4 )). Complexes 2 – 4 were characterized by multinuclear NMR ( 1 H, 13 C and 31 P NMR) and IR spectroscopy, and their structures were also determined by single crystal X‐ray diffraction. 2 and 4 represent the first examples of structurally characterized complexes of such ligands with group 6 B metal carbonyls.