Annulation of 1 H-pyrrole-2,3-diones by thioacetamide: an approach to 5-azaisatins

Beilstein J Org Chem. 2019 Feb 7:15:364-370. doi: 10.3762/bjoc.15.32. eCollection 2019.


A novel approach to 1H-pyrrolo[3,2-c]pyridine-2,3-diones (5-azaisatins) has been developed via an unprecedented annulation of pyrrolo[2,1-c][1,4]benzoxazine-1,2,4-triones by thioacetamide. A new way of C-H functionalization of thioacetamide has been discovered. The reaction proceeds under green catalyst-free conditions.

Keywords: annulation; domino reactions; isatin; nitrogen heterocycles; thioamides.