Rh(iii)-catalyzed sequential spiroannulation/lactonization of 3-aryl N-sulfonyl ketimines with 4-hydroxy-2-alkynoates by C–H bond activation

A rhodium(iii)-catalyzed C–H annulation strategy has been developed for the synthesis of a highly rigid spirobenzosultam lactones in good yields with high regioselectivity from 3-aryl N-sulfonyl ketimines and 4-hydroxy-2-alkynoates.