Insight into the Reaction of a Dinuclear Phosphinidene Complex with Nitriles

The phosphinidene complex Cp*P{W(CO)₅}₂] ( 1 ; Cp*=C₅Me₅) reacted with malononitrile to give the 1,2‐dihydro‐1,3,2‐diazaphosphinine derivative 2 . The reaction of 1 with 1,4‐benzodinitrile gave 1,4‐{{W(CO)₅}₂P‐N=C(Cp*)}₂(C₆H₄)] ( 3 ), the first example of a cumulene‐like aminophosphinidene complex. The reaction of 1 with aniline gave the aminophosphinidene complex (Ph)N(H)P{W(CO)₅}₂] ( 4 ). To compare the reactivity of benzonitrile and aniline with 1 , the phosphinidene complex 1 was reacted with three different isomers of aminobenzonitrile (2‐, 3‐, and 4‐aminobenzonitrile). These reactions gave an insight into the reaction pathway of 1 with benzonitrile derivatives. Compounds 5 , 6 a , 6 b , and 7 , which are derivatives of 1,2‐dihydro‐1,3,2‐diazaphosphinine or benzo‐2H‐1,2‐azaphospholes, were, as well as all other products, characterized by mass spectrometry, NMR and IR spectroscopy, and X‐ray structure analysis.