摘要 |
Bromhexine drug intermediates N-methyl-N-o-nitrobenzyl cyclohexylamine synthesis method , comprising the following steps: equipped with a stiffer, a thermometer and a reflux condenser, the reaction vessel was added 600-650ml cyclohexane, 0.69mol N cyclohexyl-methyl-amine (2), slowly added 0.71 -0.73mol o-nitro benzyl amine (3), continued the reaction for 7-8h, 200ml sodium chloride solution was added, cyclohexane was distilled off, the solution temperature is reduced to 10 - 13 0C, sodium sulfite solution was added to adjust the pH of solution to 8-9, extracted with the ethyl acetate solution, dehydrated with dehydrating agent, molecular sieve bleaching, ethyl acetate was distilled off under reduced pressure to get an oily liquid, vacuum distillation, collecting fractions of 105--110 0 C, got N-methyl-N-o-nitrobenzyl cyclohexylamine . |