3-Hydroxythiophene 1 spontaneously dimerises to 4,5-dihydro-5-(3-hydroxythien-2-yl)thiophen-3(2H)-one 14. 3-Hydroxythiophenes 1E and 4–10E exist in solvent-dependent equilibrium with their thiophen-3(2H)-one 1K and 4–10K tautomers; the amount of hydroxy tautomer is greater than in the case of the corresponding 3-hydroxypyrroles. 3-Hydroxythiophenes are much less reactive to electrophiles than corresponding
3-羟基
噻吩 1自发二聚为4,
5-二氢-5-(3-羟基
噻吩-2-基)
噻吩-3(2 H)-one 14。3- Hydroxythiophenes 1E和4- 10E中存在与溶剂依赖性平衡他们的
噻吩3(2 H)-one 1K和4- 10K互变异构体; 羟基互变异构体的量大于相应的
3-羟基吡咯的情况。3-羟基
噻吩对亲电试剂的反应性远低于相应的
3-羟基吡咯,但是5-
甲基硫烷基衍
生物10在2位与甲
氧基亚
甲基Meldrum的酸会经历Vilsmeier甲酰化反应。通过用碱处理衍生自3-羟基
噻吩的
烯醇化物可以以高区域选择性被O-烷基化和O-酰化。
2,2-二取代
噻吩-3(2 H)-one与亲核试剂进行平衡共轭加成,但无法分离所得的加合物。