Enantioselective Synthesis of 3,3-Disubstituted Oxindoles Bearing Two Different Heteroatoms at the C3 Position by Organocatalyzed Sulfenylation and Selenenylation of 3‑Pyrrolyl-oxindoles

Catalytic
asymmetric sulfenylation and selenenylation of 3-pyrrolyl-oxindoles
for the synthesis of 3,3-disubstituted oxindoles bearing two different
heteroatoms at the C3 position have been achieved with commercially
available cinchonidine as catalyst. A wide range of optically active
3-thio-3-pyrrolyl-oxindoles and 3-seleno-3-pyrrolyl-oxindoles could
be smoothly obtained under mild conditions with satisfactory results.
The promising applicability of the protocol was also demonstrated
by large-scale production.