title: Tripodal tetrahedral titanium coordination in the silica-grafted titania epoxidation catalysts: is not it only a myth? Selective formation of [Cy7Si7O12Ti]2(mu-OR)2(mu-ROH) cores on thermal "dissociation" of alkoxytitanasilsesquioxanes.
abstract: The molecular structures of the species crystallizing from solutions of alkoxytitanasilsesquioxanes in hydrocarbons upon reflux confirm the partial release of solvating alcohol. They feature, however, distinctly the formation of a dinuclear core with preserved hexacoordination for the metal atoms. The active titanium centers in the silica-titania epoxidation catalysts, lacking the sterically demanding ligands, are thus quite probably also hexacoordinated.
authors.affiliation: Department of Chemistry, SLU, Box 7015, 75007 Uppsala, Sweden.
authors.forename: Olle
authors.initials: O
authors.lastname: Viotti
authors.forename: Gulaim A
authors.initials: GA
authors.lastname: Seisenbaeva
authors.forename: Vadim G
authors.initials: VG
authors.lastname: Kessler