in diethyl ether treatment of diethyl ether soln. of NiP(C(CH3)3)2CH2CH2P(C(CH3)3)2NC6H3(CH(CH3)2)2 with CO (1 atm, 22 °C) over 2 h; detd. by (1)H NMR, (13)C NMR, (19)F NMR, (31)P NMR, MAS;