College of Chemistry & Chemical Engineering, Yangzhou University, Yangzhou, 225002, China.
Mol Divers. 2011 Feb;15(1):115-23. doi: 10.1007/s11030-010-9278-x. Epub 2010 Sep 17.
New, highly-functionalized dihydrothiophenes are conveniently synthesized from the novel tandem, four-component reactions of 1,3-thiazolidinedione, aldehyde, arylamine, and ethyl cyanoacetate, catalyzed by triethylamine. The reaction mechanism involves the use of Knoevenagel condensation, Michael addition, and ring-opening of 1,3-thiazolidinedione, followed by intramolecular ring closure process. The reaction is diastereoselective and only trans-2,3-dihydrothiophenes were produced in moderate yields. The functionalized dihydrothiophenes can be converted efficiently to the corresponding thiophenes by DCC dehydrogenation reaction.
新型高官能化二氢噻吩可通过 1,3-噻唑烷二酮、醛、芳胺和氰基乙酸乙酯的新型串联四组分反应，在三乙胺催化下方便地合成。反应机理涉及 Knoevenagel 缩合、迈克尔加成和 1,3-噻唑烷二酮的开环，然后进行分子内环化过程。反应具有立体选择性，仅生成中等产率的反式 2,3-二氢噻吩。通过 DCC 脱氢反应，官能化二氢噻吩可有效地转化为相应的噻吩。
