α-(2-carbo-tert.-butyloxy-3,3-dimethyl-7-oxo-4-thia-2,6-diaza-6-bicyclo[3,2,0]heptyl)-α-chloroacetic acid 2,2,2-trichloroethyl ester 在
sodium 作用下,
以
苯 为溶剂,
生成
α-(2-carbo-tert.-butyloxy-3,3-dimethyl-7-oxo-4-thia-2,6-diaza-6-bicyclo[3,2,0]heptyl)-α-(tri-n-butyl-phosphoranylidene)-acetic acid 2,2,2-trichloroethyl ester