An efficient, catalyst-free continuous flow procedure for the condensation of acid chlorides and alcohols was developed. Different esters could be obtained using this protocol with excellent conversions starting from the corresponding acid chlorides and alcohols in very short reaction times (5–7 min). The reaction was performed solventless for liquid reagents but requires a solvent for solid reagents in order to prevent clogging of the microreactor. Since no catalyst is needed, the purification of the reaction mixture is very straightforward. Scale-up of the reaction to a microreactor with an internal volume of 13.8 ml makes it possible to produce 2.2 g min−1 of ester with an isolated yield of 98% and recuperation of the formed HCl.
开发了一种高效、无催化剂的连续流动工艺,用于酸
氯化物和醇的缩合反应。通过这一工艺,从相应的酸
氯化物和醇出发,在非常短的反应时间内(5-7分钟)即可获得高转化率的
酯类化合物。该反应对于液体试剂是无溶剂进行的,但对于固体试剂则需要溶剂,以防止微反应器堵塞。由于无需催化剂,反应混合物的纯化过程非常直接。将反应规模扩大至内体积为13.8毫升的微反应器,能够实现以98%的分离产率每分钟生产2.2克酯,并回收生成的HCl。