Catalytic behaviors of silica-supported chitin–platinum complex for asymmetric hydrogenation of α-phenylethanol

✍ Scribed by Guo-Li Yuan; Mao-Ya Yin; Ting-Ting Jiang; Mei-Yu Huang; Ying-Yan Jiang

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 129 KB
• Volume: 159
• Category: Article
• ISSN: 1381-1169
• DOI: 10.1016/s1381-1169(00)00169-2

✦ Synopsis

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. Silica-supported chitin-platinum complex SiO -CT-Pt has been prepared and found to be a high stereoselective 2 Ž . catalyst for asymmetric hydrogenation of racemic a-phenylethanol to Rq -1-cyclohexyl ethanol at 308C and under an Ž . atmospheric hydrogen pressure. The optical selectivity of Rq -1-cyclohexyl ethanol amounted to 100% when a fitting condition was selected. In this case, the yield and optical selectivity were affected greatly by many factors, such as Pt content in SiO -CT-Pt complex, the reaction temperature, the solvent, and the amount of the additive of hydrochloric acid, 2 Ž . etc. SiO -CT-Pt catalyst also has shown high stability. The optical selectivity for Rq -1-cyclohexyl ethanol was almost 2 keeping at 100% when the catalyst was reused for many times. Moreover, SiO -CT-Pt complex is an economical chiral 2 catalyst. The chitin is an abundant natural biopolymer and the procedure for preparation of the complex is very simple.