SYNTHESIS OF ACTIVE-SITES FOR ALKENE METATHESIS REACTION ON MOLYBDENUM AND TUNGSTEN-OXIDE FILMS

Two methods were developed for the synthesis of active sites for the alkene metathesis reaction on sublimed oxide films (MoOx and WOx). One method involves the reaction of the oxide films with alkyl radicals which are themselves produced by reacting condensed alkenes on the films at liquid nitrogen temperature with atomic hydrogen. The other method is the reaction of the oxide films with CH2 radicals which are produced by the reaction of CH2I2 on Al or Mg metals. Both methods were effective for activation of the MoOx films, yielding catalysts with turnover frequencies as large as 0.6 s-1 (3 Torr propene at room temperature). However, the first method was less effective for the activation of WOx film. The isomerization and the hydrogen scrambling reactions of alkenes were also studied. © 1990.