摘要
以丙醛为原料,经自缩合合成了中间体2-甲基-2-戊烯醛,再经NaClO2氧化合成了2-甲基-2-戊烯酸。较佳反应条件为:第一步,NaOH/丙醛(摩尔比)=0.09:1,w(NaOH)=2%,40℃反应45min,收率为93%;第二步,NaClO2/醛(摩尔比)=1.6:1,H2O2/醛(摩尔比)=1.2:1,反应时间3h,乙腈用量50mL,反式2-甲基-2-戊烯酸摩尔收率约85%,产物经IR和1HNMR确证了结构。
(E)-2-methyl-2-pentenoic acid was prepared from propanal as raw material in two steps. Firstly, the intermediate 2-methyl-2-pentanal was synthesized by self-condensation of propanal on the conditions; sodium hydrate/propanal (molar ratio)=0.09∶1, w( sodium hydrate) =2%. reaction temperature 40℃. reaction time 45 min, the yield of aldehyde was 93%; in the second step, (E)-2-methyl-2-pentenoic acid was synthesized by oxidation of 2-methyl-2-pentanal with a cheap efficient oxidant-sodium chlorite(NaClO2). The optimum conditions of oxidation reaction were as follows: NaClO2/aldchyde(molar ratio) = 1. 6∶1, H2 O2/aldehyde( molar ratio) = 1.2∶1, reaction time 3 h. acetonitrile 50 mL, the yield of the product was up to 85% , and its structure was confirmed by IR and 1H NMR.
出处
《精细石油化工》
CAS
CSCD
北大核心
2005年第2期22-24,共3页
Speciality Petrochemicals