Synthesis and ligand metathetical reactions of supported transesterification catalyst models

Surface Characterization and Modification of Indium Tin Oxide in Ultrahigh Vacuum

“…Ligand groups in the coordination sphere of ITO surface bound Sn (or Zr) complexes react with organics of acidity greater than that of tert -butyl alcohol to give a variety of surface-modified ITO materials. Indeed, surface phenoxide and carboxylate derivatives of Sn have been prepared on other oxide surfaces by simple ligand exchange with phenols 35 and carboxylic acids …”

Reaction of Tetra(tert-Butoxy)Tin or -Zirconium with Hydroxylated Titanium in Ultrahigh Vacuum: Contrasting Reactivity with Hydroxylated Aluminum Substrate

“…We have previously reported 1 that tetra( tert -butoxy)zirconium ( 1 ) deposits on the hydroxylated oxide layer of Al − at 170 K, and on warming to 270 K, gives [Al]−[O]−Zr(OBu t ) 3 ( Al-2 ). If the Al surface was heavily hydroxylated, then [Al]−[O] 2 −Zr(OBu t ) 2 ( Al-3 ) formed on further heating to 350−400 K; however, if the surface was only lightly hydroxylated, then only total ligand decomposition occurred over 300 K. Analogous behavior was noted for the reaction of 1 with hydroxylated Al under “normal” laboratory conditions. , In contrast, tetra( tert -butoxy)tin ( 4 ) deposits on and reacts with hydroxylated Al to give [Al]−[O]−Sn(OBu t ) ( Al-5 ) as the only detectable tin organometallic, either in ultrahigh vacuum (UHV; 220−270 K), or at room temperature under “normal” conditions. , No intermediate polyalkoxide complex precursors were found: because desorption of the multilayer of 4 occurs only at ca. 220 K in UHV, observation of any chemisorbed species of low thermal stability that might have been formed was precluded.…”