Synthesis of Thiophene Derivatives on Soluble Polymer-Support Using Gewald Reaction
Haiqing Zhang, Guichun Yang*, Jianian Chen, Zuxing Chen
*Faculty of Chemistry and Material Science, Hubei University, Wuhan, Hubei, 430062, P. R. China, Email: ygc33tom.com
H. Zhang, G. Yang, J. Chen, Z. Chen, Synlett, 2004, 3055-3059.
The Gewald reaction of PEG-bound cyanoacetic ester, elemental sulfur, DIPEA and carbonyl compounds carried out under microwave irradiation afforded PEG-supported thiophenes, which were acylated and treated with 1% KCN in methanol to give free thiophenes in good yields. This synthetic method is simple and mild.
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