A Lanthanide Phosphinidene Complex: Synthesis, Structure, and Phospha-Wittig Reactivity

The first lanthanide complex featuring a phosphinidene functional group has been prepared and isolated. Preliminary reactivity studies demonstrate that the lutetium(III) phosphinidene complex, [{2-( i Pr 2 P)-4-Me-C 6 H 3 } 2 NLu] 2 (μ-PMes) 2, behaves as a phospha-Wittig reagent with aldehydes and ketones to give the corresponding phosphaalkenes. Attempts to use the bulky phosphine H 2 P-2,4,6- t Bu 3 -C 6 H 2 to kinetically stabilize a terminal phosphinidene resulted in C−H activation of an ortho - t Bu group and formation of a phosphaindole.