Homometallic Rare‐Earth Metal Phosphinidene Clusters: Synthesis and Reactivity

Two new trinuclear μ 3 ‐bridged rare‐earth metal phosphinidene complexes, [{L(Ln)(μ‐Me)} 3 (μ 3 ‐Me)(μ 3 ‐PPh)] (L=[PhC(NC 6 H 4 i Pr 2 ‐2,6) 2 ] − , Ln=Y ( 2 a ), Lu ( 2 b )), were synthesized through methane elimination of the corresponding carbene precursors with phenylphosphine. Heating a toluene solution of 2 at 120 °C leads to an unprecedented ortho  CH bond activation of the PhP ligand to form the bridged phosphinidene/phenyl complexes. Reactions of 2 with ketones, thione, or isothiocyanate show clear phospha‐Wittig chemistry, giving the corresponding organic phosphinidenation products and oxide (sulfide) complexes. Reaction of 2 with CS 2 leads to the formation of novel trinuclear rare‐earth metal thione dianion clusters, for which a possible pathway was determined by DFT calculation.