Vapour-phase O-methylation of Catechol with Methanol on Ti-containing Phosphate Catalysts  

作　　者：ZHU Xiao-mei LI Xue-mei LIU Gang ZOU Xiu-jing WANG Yan-li JIA Ming-jun ZHANG Wen-xiang 

机构地区：[1]College of Chemistry, Jilin University, Changchun 130021, P. R. China [2]Shanghai Huayi Acrylic Acid Co. Ltd. , Shanghai 200137, P. R. China

出　　处：《Chemical Research in Chinese Universities》2006年第4期533-536,共4页高等学校化学研究（英文版）

基　　金：Supported by the Development Project of Science and Technology of Jilin Province(Nos. 20050309-1 and 20040563), the Spe-cialized Research Fund for the Doctoral Program of Higher Education(No.20040183003), CNPC(No.JTGS 20040010), and the Na-tional Natural Science Foundation of China(No.20403006)

摘　　要：Ti-containing phosphate（ Ti-P-O ） catalysts with different molar ratios of P to Ti （0--2. 0 ） were synthesized and characterized by XRD, N2-adsorption/desorption, IR and temperature-programmed desorption （TPD） methods. The catalytic properties of Ti-P-O samples in the vapor-phase O-methylation of catechol with methanol were also studied. The catechol conversion increases with the increase of the molar ratio of P to Ti in a range of 0-0. 33, while a further increase in the P content leads to a decrease of the catalytic activity. Meanwhile, the selectivities of the catalysts to the main product（guaiacol） increase gradually with the increase of the molar ratio of P to Ti. The presence of relatively strong Lewis acidic and/or basic sites in the P-free catalyst should be responsible for the formation of C-alkylation products. The weak acid-base characteristics of the catalysts are favourable for the mono-O-methylation of catechol. In comparison with the Lewis acidic sites, the Bronsted acidic sites on the catalysts are more active for the title reaction.Ti-containing phosphate（ Ti-P-O ） catalysts with different molar ratios of P to Ti （0--2. 0 ） were synthesized and characterized by XRD, N2-adsorption/desorption, IR and temperature-programmed desorption （TPD） methods. The catalytic properties of Ti-P-O samples in the vapor-phase O-methylation of catechol with methanol were also studied. The catechol conversion increases with the increase of the molar ratio of P to Ti in a range of 0-0. 33, while a further increase in the P content leads to a decrease of the catalytic activity. Meanwhile, the selectivities of the catalysts to the main product（guaiacol） increase gradually with the increase of the molar ratio of P to Ti. The presence of relatively strong Lewis acidic and/or basic sites in the P-free catalyst should be responsible for the formation of C-alkylation products. The weak acid-base characteristics of the catalysts are favourable for the mono-O-methylation of catechol. In comparison with the Lewis acidic sites, the Bronsted acidic sites on the catalysts are more active for the title reaction.

关 键 词：PHOSPHATES Acid-base catalysis GUAIACOL CATECHOL O-METHYLATION 

分 类 号：O625.312[理学—有机化学] O643.3[理学—化学]