Transition metal-substituted acylphosphines and phosphaalkenes. Part 35. Unprecedented coupling of a transition metal carbyne and a methylene phosphine moiety. Structure of [Tp'(CO)2W.tplbond.CP:C(NEt2)2] [Tp' = tris(3,5-dimethyl-1,2-diazolyl)boryl].

Condensation of [Tp'(CO)2M.tplbond.CCl] (M = Mo, W, Tp' = tris(3,5-dimethyl-1,2-diazolyl)boryl) with the inverse phosphaalkenes Me3SiP:C(NR2)2 (R = Me, Et) affords the corresponding (phosphaalkenyl)carbyne complexes [Tp'(CO2)M.tplbond.CP:C(NR2)2] which were characterized by IR and 1H, 13C, and 31P NMR. In addn., the mol. structure of [Tp'(CO)2W.tplbond.CP:C(NEt2)2] was elucidated by single-crystal x-ray structure detn.