Synthesis of Spirooxindoles Bearing 1,3‐Oxathiolane‐2‐thione Moiety From Isatin‐Derived Propargylic Alcohols

Spirooxindoles bearing 1,3‐oxathiolane‐2‐thione moiety were synthesized from isatin‐derived propargylic alcohols and carbon disulfide in the presence of 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU). The spirooxindoles were formed stereoselectively via attack of the alkoxide of propargylic alcohol to carbon disulfide to form xanthate anion and a following 5‐exo‐dig cyclization process. Synthesis of spirooxindoles bearing 1,3‐oxathiolane‐2‐thione moiety.