AbInitio Study on the Isomerization of 3-Hydroxy-2-pyridone

Ab initio calculations at RHF/6 31G and MP2/6 31G levels have been applied to study the isomerization of 3 hydrox 2 pyridone.The results obtained show that this isomerization proceeds to itself isomer via a four center cyclic transition state (TS1) in the gas phase,and vis six center cyclic transition state (TS2) in water.The activation energy of the route(2) through a six center cyclic transition state TS2 is lowest(79.274 8(RHF/4 31G),82.413 8(RHF/6 31G) and 59.403 5(MP2/6 31G)kJ·mol -1 ).