A nonhydrolytic sol‐gel route based on the condensation between chlorides
and oxygen donors such as ethers and alkoxides is presented. Four examples,
silica, alumina, titania and binary oxides in the Al/Si system show that
this is a general route. The mechanism of this condensation is completely
different from the one of classical sol‐gel process, since it implies
nucleophilic substitution at the carbon center instead of the metal center.
As a consequence, the differences in reactivity between different metals are
reduced. In addition, the structure of the precursors may be retained in the
gel. Thus, the nonhydrolytic sol‐gel process is very efficient for the
preparation of homogeneous bicomponent oxides. Futhermore, nonhydrated gels
are formed, which allowed us to prepare amorphous aluminas with high surface
areas.