文献类型：期刊文献

中文题名：A One-pot Approach to Ethyl 1,4,5-Triaryl-lH-pyrazole-3- carboxylates via an Improved Claisen Condensation- Knorr Reaction Sequence

英文题名：A One-pot Approach to Ethyl 1,4,5-Triaryl-lH-pyrazole-3- carboxylates via an Improved Claisen Condensation- Knorr Reaction Sequence

作者：Jiaojiao Zhai[1];Chunhui Gu[1];Jianan Jiang[1];Shunli Zhang[1];Daohua Liao[1];Lei Wang[2];Dunru Zhu[2];Yafei Ji[1]

机构：[1]School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China;[2]State Key Laboratory of Materials-oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing, Jiangsu 210009, China

年份：2013

卷号：31

期号：12

起止页码：1526

中文期刊名：Chinese Journal of Chemistry

外文期刊名：中国化学（英文版）

收录：CSTPCD;;Scopus;CSCD:【CSCD2013_2014】；

基金：The authors are grateful to the National Natural Science Foundation of China (Nos.21176074 and 21171093) for financial support

语种：英文

中文关键词：one-pot approach;2,4-dioxo-3,4-diarylbutanoates;Claisen condensation;Knorr reaction;triarylpyrazole-3-carboxylates

外文关键词：one-pot approach, 2,4-dioxo-3,4-diarylbutanoates, Claisen condensation, Knorr reaction, triarylpyrazole-3-carboxylates

摘要：A one-pot approach to ethyl 1,4,5-triaryl-lH-pyrazole-3-carboxylates has been developed in moderate to high yields. The tert-BuOLi-mediated Claisen condensation of 1,2-diarylethanones and ethyl oxalyl chloride efficiently provided the enolized lithium salts of ethyl 2,4-dioxo-3,4-diarylbutanoates, which in situ reacted with arylhydrazine hydrochlorides via a hydrochloric acid-promoted Knorr reaction to produce the exquisite triarylpyrazole-3- carboxylates. The procedure promises a convenient access to this highly crowded framework for drug discovery.
A one-pot approach to ethyl 1,4,5-triaryl-lH-pyrazole-3-carboxylates has been developed in moderate to high yields. The tert-BuOLi-mediated Claisen condensation of 1,2-diarylethanones and ethyl oxalyl chloride efficiently provided the enolized lithium salts of ethyl 2,4-dioxo-3,4-diarylbutanoates, which in situ reacted with arylhydrazine hydrochlorides via a hydrochloric acid-promoted Knorr reaction to produce the exquisite triarylpyrazole-3- carboxylates. The procedure promises a convenient access to this highly crowded framework for drug discovery.