Abstract The tautomeric system of 3-hydroxy-2-(2-thienylcarbonyl) cyclohex-2-en-1-one 1 has been investigated by NMR spectroscopy between 224 and 298 K. At all temperatures an endocyclic enol tautomer was the major isomer; however, at low temperatures two other enol isomers were found. Conformational search of the potential energy surfaces of all tautomers of cyclohexenone 1 was also carried out. Extensive calculations were ...
![2-[hydroxy(phenyl)methylidene]cyclohexane-1,3-dione结构式](https://image.chemsrc.com/caspic/164/61834-43-3.png)