Hydrogenation of m-xylene catalyzed by a silica-supported polysilazane–platinum complex

✍ Scribed by Chun-Wei Chen; Hong Yu; Mei-Yu Huang; Ying-Yan Jiang

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 363 KB
• Volume: 7
• Category: Article
• ISSN: 1042-7147
• DOI: 10.1002/(sici)1099-1581(199602)7:2<79::aid-pat444>3.0.co;2-k

✦ Synopsis

A new kind of inorganic polymer, silica-supported polysilazane (Si-N), and its platinum complex (Si-N-Pt) were prepared and characterized by X-ray photoelectron spectroscopy. It was found that Si-N-Pt can catalyze hydrogenation of m-xylene under mild conditions (30-50"C, 1 atrn). The products of the reaction were cis-and trans-l,3-dimethylcyclohexane. The formation of trans-1,3-dimethylcyclohexane may be adequately explained according to the "roll-over" model. The stereoselectivity was influenced by temperature and catalyst concentration, the proportion of the cis isomer decreasing with an increase in each of the two factors. The effects of other reaction parameters, such as the NIPt mole ratio in the complex, solvents and reaction time, etc., on the hydrogenation of m-xylene were also studied. The Si-N-Pt catalyst is very stable in reaction and turnover numbers amount to 520 in 70 hr.