Amine functionalized silica catalysts, including (3-aminopropyltrimethoxysilane (APTMS)) NH2/SiO2, (Diazabicycloundecene/SiO2) DBU/SiO2 and (1, 5, 7-triazabicyclo [4, 4, 0] dec-5-ene/SiO2) TBD/SiO2, which were characterized by 29Si NMR, elemental analysis and indicator dye adsorption, were prepared by ultrasonic technique under mild conditions. Such hybrid solid bases showed high catalytic activity and well reusability towards the methylation reaction of phenol with dimethyl carbonate (DMC).

Xuehong Zhang, Shubin Liu, Yanlei Gao, Yunxiao Zhang, Lei Ren Ruisheng Hu and Rufen Chen