Ultrasonically-promoted synthesis of mandelic acid by phase transfer catalysis in an ionic liquid
Qian Hua1, Liu Dabin, Lv Chunxu
1Chemical Engineering School, Nanjing University of Science and Technology, Nanjing, People's Republic of China. jyqianhua@yahoo.com.cn
Abstract:
An efficient and facile process to synthesize mandelic acid through phase transfer catalysis (PTC; also phase transfer catalyst) using ultrasound in an ionic liquid has been developed. Mandelic acid was synthesized from benzaldehyde with chloroform in an 89.6% yield at 60°C for 2h by using tetrabutyl ammonium bromide (TBAB) as a phase transfer catalyst. Effects of different factors, such as frequency of ultrasound, reaction temperature, kinds of PTC and solvents had been investigated to obtain the optimum condition. It was observed that the ultrasonically promoted synthesis of mandelic acid by PTC in the ionic liquid exhibited significant enhancement in reaction yields under ambient conditions.
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