Phosphinidene group-transfer with a phospha-Wittig reagent: a new entry to transition metal phosphorus multiple bonds.

The phosphanylidene-sigma(4)-phosphorane reagents Me(3)P[double bond, length as m-dash]PAr (Ar = 2,4,6-(t)Bu(3)C(6)H(2) and 2,6-Mes(2)C(6)H(3)) are good delivery vehicles of the terminal phosphinidene moiety, PAr, to early-transition metals composed of zirconium and vanadium.