Surface Organometallic Chemistry on Metals:  Evidence for the Formation of a Stable (Rhs)2Ge(H)(CH2)4OH Fragment at the Surface of a Rhodium Nanoparticle

A grafted organogermanium moiety was observed on a rhodium surface, starting with an organogermane compound, (Ad)GeH3 (Ad = adamantyl) (Taoufik et al. J. Am. Chem. Soc. 1996, 118, 4167). Recently, new surface germanium complexes with functional groups grafted on Pt and Rh particles were prepared by reaction under hydrogen in propan-2-ol of organogermane complexes H3GeRf (Rf = −R−OH or R−OMe) with the surface of rhodium catalysts (Tena et al. J. Mol. Catal. 1999, 146, 53). It is proposed that grafted organometallic fragments with formula Rhs[H x GeRf y ] z /SiO2 could be stabilized on the metallic surface. This paper reports the characterization by various physical techniques of the surface complexes obtained by reaction of H3Ge−(CH3)4−OH with the reduced surface of rhodium catalysts supported on silica.