噻唑衍生物的Vilsmeier甲酰化反应活性的比较

Comparison of the reactivity of Vilsmeier formylation on thiazole derivatives

目的考察不同取代基对噻唑环Vilsmeier反应活性的影响。方法设计合成了含7种不同取代的噻唑底物,并考察了Vilsmeier反应的活性。结果和结论含有芳香族取代基的底物进行Vilsmeier反应的收率要低于含脂肪族取代基的底物,不同脂肪族取代基之间,随着碳链的增长,底物的反应活性也有增加的趋势,但是当取代基为正丁基或叔丁基时,反应活性又较异丁基有所下降。

OBJECTIVE To investigate the effects of different substituents on the reactivity of Vilsmeier formylation of thiazole ring.METHODS Seven thiazole derivatives containing different substituents were designed and synthesized.Their reactivity of Vilsmeier formylation were investigated.RESULTS and CONCLUSION Substrates with aromatic substituents have low reactivity in Vilsmeier reactions comparing substrate with aliphatic substituents.Among the aliphatic substrate,reactivity of the substrates tends to be higher when the carbon chain is longer.But as the subsituents is n-butyl or t-butyl,reactivity is lower than i-butyl,which might be the results of steric factor.