Monomeric Phosphanylgalanes - Synthesis and Structural Characterization

The monomeric phosphanylgallanes R2GaPR'R (R = tmp, Mes; R' = H, tBu; R' Mes, tBu), the diphosphanylgallane mesGa(PtBu2)2, and diphosphandiylbisgallane [tmp2GaP‐(tBu)]2, have been synthesized from alkali metal phosphides and substituted gallium chlorides. Low‐temperature NMR studies of the phosphanylgallanes reveal no barrier to rotation about the gallium‐phosphorus bond. Analysis of the crystal structures of tmp2GaPtBu2 confirms the monomeric nature of these molecules. The gallium‐phosphorus bond lengths are found to be 237.5, 233.5, 235.4 pm (averaged), and 242.3 pm, respectively, with all phosphorus atoms being pyramidally coordinated.