tert-butyl 3-(2-ethoxy-2-oxoethylidene)-2-oxoindole-1-carboxylate 在
13-Hydroxy-10-(13-hydroxy-13-oxo-12,14-dioxa-13lambda5-phosphapentacyclo[13.8.0.02,11.04,9.016,21]tricosa-1(15),2,4,6,8,10,16,18,20,22-decaen-10-yl)-12,14-dioxa-13lambda5-phosphapentacyclo[13.8.0.02,11.04,9.016,21]tricosa-1(15),2,4,6,8,10,16,18,20,22-decaene 13-oxide 、
三氟乙酸 作用下,
以
二氯甲烷 为溶剂,
反应 4.25h,
生成
ethyl (1'S,3R,3'R)-2,5'-dioxo-1'-phenyl-6',7'-dihydro-1'H,3'H,5'H-spiro[indoline-3,2'-pyrazolo[1,2-a]pyrazole]-3'-carboxylate