Silica-polyvinylpyridine-Pd(II) complexes as hydrogenation catalysts

Silica-supported polyvinylpyridine-Pd(OAc)2 and-PdCl2 complexes have been prepared and demonstrated to be very active catalysts for the hydrogenation of alkenes at room temperature and 1 atmosphere pressure. They are very active and more stable than other polymer-supported Pd catalysts reported earlier. A comparison of the activity of catalysts (I) and (II) in the hydrogenation of cyclohexane, a substrate often studied, with values reported in the literature on palladium-bound catalysts is shown. It is observed that under identical reaction conditions, the activities of catalysts (I) and (II) are much higher than those in most other documented reports. The higher activity of these catalysts may be attributed to their large surface area, which is found to be equal to 220m2g-1.