With transition metals, Pd, Pt, Co, loaded on the mesoporous materials, organic reactions (hydrogenation, hydrogenolysis, Heck reaction, and Pauson-Khand reaction) were investigated and new selectivity, compared with the reaction of other catalyst, was found.
Pd@MCM48 selectively hydrogenolyzed benzyl ether of molecules including double bonds while other Palladium catalysts have no selectivity between hydrogenation and hydrogenolysis. And benzyl bromide makes hydrogenolysis to be 3 times faster, but it has no effect on hydrogenation. Pd@MCM48 hydrogenolyzed completely 1° benzyl ether but the hydrogenolysis of 2° and 3° benzyl ether wasn’t observed in the mixture of 1°, 2° and 3° benzyl ethers.
Hydrogenation of the olefin including benzyl ether with Pt/CMK-1 gave no debenzylated product until the hydrogenation finished, while the hydrogenation with Pt/C gave 10% debenzylated product. The relative rates of hydrogenation with Pt/CMK-1 of di- and tri-substituted olefins were about two orders of magnitude slower than mono-substituted olefin. In the case of Pt/C, the relative rates of di- and tri-substituted olefins were about 3 times slower than mono-substituted olefin.
The heterogeneous Pauson-Khand reaction with $Co_2(CO)_8$/MCM48 and $Co_2(CO)_8$/CMK-1 gave 20% yield and 26% yield. In according to the mechanism of Pauson-Khand reaction only one carbonyl group is participated. But we observed that only 0.35 equivalent of $Co_2(CO)_8$ in DME under a Ar atm gave 70% yield.