The reaction of tetrabutyltin with an alumina-containing inorganic oxide su
ch as alumina, silica-alumina or boria-alumina, gives active catalysts for
olefin metathesis. Infrared results obtained with tin-modified gamma-alumin
a and boria-alumina suggest that the active sites arise from an interaction
between (n-Bu)(4)Sn and a coordinatively unsaturated Al site, which is cre
ated when bridging OH groups react with the tetraalkyltin compound. (C) 199
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