Polyoxometalates dehydrogenation

Marchal-Roch, C. Bayer, R. Moisan, J.F. Teze, A. Herve, G. Oxidative dehydrogenation of isobu-tyric acid Characterization and modeling of vanadium containing polyoxometalate catalysts. Top. Catal. 1996, 5,407-419. 

Studies with unpromoted and Pt-promoted solid acids, specifically, H morde-nite,308 Pt Beta-zeolite,313 and acidic polyoxometalate cesium salts314,315 applied in the presence of hydrogen, showed that the isomerization of n-butane follows a monomolecular pathway. This consists of dehydrogenation on the metal site and isomerization on acidic sites. A new study using isotope labeling provided direct... 

Polyoxometalate-pillared hydrotalcites were also screened for activity for the dehydrogenation of t-butylethylbenzene to t-butylstyrene. Table III shows that molybdate-pillared hydrotalcites outperformed other pillared hydrotalcites. 

Fig. 2. Photocatalytic Oxidation/Dehydrogenation of Substrates, SubH2, by Polyoxometalates. Pox represents the oxidized and resting form of the polyoxometalate Pf d represents the reduced form of the polyoxometalate.

Dimitratos, N. and Vedrine, J.C. Role of acid and redox properties on propane oxidative dehydrogenation over polyoxometallates. Catal Today 2003, 81, 561-571. 

As can be concluded from the details presented in this section of the review, the variety of properties available in polyoxometalate compounds enables them to be used for aerobic oxidation, which may proceed by a number of mechanistic schemes. In some cases, practical synthetic techniques are already available, especially for aerobic alcohol oxidation and other oxidative dehydrogenation reactions. In other... 

---