An efficient and practical synthesis of methylene dioximes by combination of ultrasound and phase transfer catalyst.
The reaction of oximes with dichloromethane was carried out in 71-98% yields at 20-30 degrees C for 2-3.5h in the presence of sodium hydroxide by combination of benzyldimethyltetradecylammonium chloride and ultrasonication. The main advantage of the present procedure is that the reaction time is much shorter than classical methods.
Li
Ji-Tai
JT
College of Chemistry and Environmental Science, Hebei University, Key Laboratory of Analytical Science and Technology of Hebei Province, Baoding 071002, PR China. lijitai@mail.hbu.edu.cn
Li
Xiao-Liang
XL