以多聚甲醛为原料,在三甲胺的催化下与正丁醛发生羟醛缩合反应制备2,2-二羟甲基丁醛.GC、GC - MS分析发现2,2-二羟甲基丁醛为主产物、2-乙基丙烯醛为最主要的副产物.通过对无机碱、有机碱催化剂进行筛选,发现三甲胺水溶液为较优催化剂.当以10％的水为反应溶剂,多聚甲醛∶正丁醛∶三甲胺=2.5∶1.0∶0.050(摩尔比)时,在80℃反应2h后,正丁醛转化率为91％,2,2-二羟甲基丁醛的选择性为78％,得率为71％.以固体甲醛替代甲醛水溶液有利于减少含醛废水的排放,符合绿色化学的发展趋势.%PFA was used instead of formaldehyde solution to react with butyraldehyde for preparing 2,2 - dimethylol - 1 - bu-tanal. GC and GC - MS results showed that the main product was 2,2- dimethylol - 1 - butanal while 2 - ethylacrylaldehyde was the principal by - product. Among the inorganic base and organic base catalysts, teimethylamine was found to be the optimal one. When using water as solvent and at PFA: butyraldehyde: trimethylamine (molar ratio) of 2. 5: 1.0: 0. 050,the conversion of butyraldehyde was 91 % after reaction for 2 h under 80 ℃ , corresponding to the selectivity and the yield of 2,2 - dimethylol - 1 - butanal of 78% and 71% Respectively.
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