Phosphane-functionalized heavier tetrylenes: synthesis of silylene- and germylene-decorated phosphanes and their reactions with Group 10 metal complexes

Abstract

The stable phosphane-functionalized heavier tetrylenes E(^tBu₂bzam)pyrmP^tBu₂ (E = Si (1_Si), Ge (1_Ge); ^tBu₂bzam = N,N′-ditertbutylbenzamidinate; HpyrmP^tBu₂ = ditertbutyl(2-pyrrolylmethyl)phosphane) have been prepared by reacting the amidinatotetrylenes E(^tBu₂bzam)Cl (E = Si, Ge) with LipyrmP^tBu₂. The reactions of 1_Si and 1_Ge with selected M⁰ and M^II (M = Ni, Pd, Pt) metal precursors have allowed the synthesis of square-planar [MCl₂{κ²E,P-E(^tBu₂bzam)pyrmP^tBu₂}] (M = Ni, Pd, Pt; E = Si, Ge), tetrahedral [Ni{κ²E,P-E(^tBu₂bzam)pyrmP^tBu₂}(cod)] (E = Si, Ge; cod = 1,5-cyclooctadiene) and triangular [M{κ²E,P-E(^tBu₂bzam)pyrmP^tBu₂}(PPh₃)] (M = Pd, Pt; E = Si, Ge) complexes, showing that 1_Si and 1_Ge are excellent Si,P- and Ge,P-chelating ligands that, due to their large steric bulk, are able to stabilize three-coordinate Pd⁰ and Pt⁰ complexes.