Thiazoline-azetidinone(7) 화합물은 $CH_2Cl_2-H_2O$ 용매에서 요오드와 반응하면 직접 3-iodo-3-methylcepham(4)을 준다. 이 반응은 상이동 촉매를 사용하면 훨씬 빨라지며 0.1당량의 요오드를 사용하면 약산성 존건하의 가수분해 반응과 비슷하게 thiazole(10)이 주생성물이었다. 고리화 반응과 가수분해 반응차이는 사용된 요오드량 및 thiazoline-azetidinone 화합물에 따라 설명될 수 있다.
The reaction of thiazoline-azetidinone (7) with $I_2$ in $CH_2Cl_2-H_2O$ gave directly 3-iodo-3-methylcepham (4). A phase transfer catalyst considerably increased the reaction rate. Similar to the hydrolysis of thiazoline-azetidinone (7) under a weak acidic condition, thiazole (10) was given as major product in the treatment with 0.1 eq. of iodine. The difference between cyclization reaction and hydrolysis could be explained in terms of solvents, the amount of iodine and the nature of thiazoline-azetidinones (7).
