摘要
采用溴化氢的冰乙酸溶液与苯酚的混合物快速脱除N–苯磺酰基–4–乙酰基哌啶–4–羧酸乙酯中的苯磺酰基,避免了酸解法脱除苯磺酰基引起反应物的脱羧反应,得到了目标产物4–乙酰基哌啶–4–羧酸乙酯,产率和纯度高。通过对脱除反应液的分析,表明溴化氢的冰乙酸溶液与苯酚的混合物对苯磺酰基的脱除可能是一个氧化-还原过程,苯酚在其中起了消除溴并防止脱除产物溴化的作用。
Hydrogen bromide in acetic acid in presence of phenol was employed as a reagent for the rapid cleavage of benzenesulfonyl group from ethyl -4-carboxylate. Decarboxylation of the reactant, which occurred when acidic hydrolysis was used as a method for the cleavage of benzenesulfonyl group, was avoided. The target product obtained was in high yield and purity. It was deduced that the cleavage mechanism may be an oxidation-reduction process involving the benzenesulfonyl group and hydrogen bromide by analyzing compounds in cleavage solution. Bromination of cleavage product was prevented by removing bromine with phenol.
出处
《广东化工》
CAS
2009年第5期29-30,95,共3页
Guangdong Chemical Industry
关键词
溴化氢
苯酚
苯磺酰基
氧化-还原过程
hydrogen bromide
phenol
benzenesulfonyl group
oxidation-reduction process
