Careful study of the reaction of lla and PCls revealed that desired 3-sulfolene 16 could be obtained as long as the molar ratio of the reactantas, the reaction time, and the reaction temperature were properly controlled (Table 1). Long reaction time and high temperature brought
![2-phenyl-4,6-dihydrothieno[3,4-d][1,3]oxazole 5,5-dioxide Structure](https://image.chemsrc.com/caspic/088/156144-31-9.png)
