Synthesis, characterisation, and catalytic activity of a phosphinidene stabilised tethered triruthenium cluster

Abstract

A high-yield synthesis of [Ru₃(µ-H)₂(CO)₉{µ₃-PCH₂CH₂Si(OEt)₃}](1) from [Ru₃(CO)₁₂](2) has been developed. This complex can be tethered to high surface area oxide supports. The alumina based material has been characterised by i.r. and u.v.–visible spectroscopies and ³¹P cross polarisation magic angle spinning n.m.r., all of which yield comparable data to that obtained for the precursor in solution. Comparison of the chemical shift anisotropy of (1)–alumina with that of a polycrystalline sample of [Ru₃(µ-H)₂(CO)₉(µ₃-PPh)](3) is consistent with (1) being firmly tethered to the oxide surface. Ruthenium K-edge extended X-ray absorption fine structure data were obtained for (1) and its alumina tethered version. Analysis of each required two Ru–Ru distances, as expected for the isosceles metal triangle in these complexes. For the tethered complex, these distance were 275(1) and 294(1) pm for the Ru–Ru and Ru–H–Ru units respectively.