An improved process for the preparation of codeine from morphine comprises the steps of a) reacting morphine with a methylating agent in the presence of a hydrocarbon solvent at a temperature of 100 to 215° C. under reflux conditions such that approximately 50% or more of the hydrocarbon solvent is returned to the reaction mixture to substantially avoid the formation of codeine methyl ether; and b) recovering codeine from the reaction mixture. The process may include step a) above followed by b) cooling the reaction mixture to approximately 85° C. and adding water to terminate the reaction; c) raising the pH of the reaction mixture to approximately 11; d) separating the hydrocarbon solvent phase containing codeine and dimethylaniline; and e) adding a dilute mineral or organic acid and approximately 6 to 7 times the volume of water for each volume of hydrocarbon solvent to separate dimethylaniline and codeine.
一种改进的从
吗啡制备
可待因的工艺,包括以下步骤:a)在反流条件下,在100至215°C的温度下,在烃溶剂的存在下,将
吗啡与甲基化剂反应,使约50%或更多的烃溶剂回流到反应混合物中,以实现基本避免形成
可待因甲醚;和b)从反应混合物中回收
可待因。该工艺可以包括上述步骤a),然后进行b)步骤,即将反应混合物冷却至约85°C,并加入
水以终止反应;c)将反应混合物的pH值提高至约11;d)分离含有
可待因和二甲基
苯胺的烃溶剂相;和e)加入稀释的矿物质或有机酸以及每个烃溶剂体积的约6至7倍的
水来分离二甲基
苯胺和
可待因。