Alum-Catalyzed Synthesis of 3-(1H-Pyrrol-2-yl)-2H-chromen-2-ones: A Water–PEG 400 Binary Solvent Mediated, One-Pot, Three-Component Protocol

The single-crystal X-ray structure of 4c (Figure 4 of the article) shows that the actual products 4a–p are 3-(1H-pyrrol-3-yl)-2H-chromen-2-ones and not 3-(1H-pyrrol-2-yl)-2H-chromen-2-ones as drawn throughout the manuscript and the supporting information. The corrected structures are now shown below.

In addition, the original mechanism outlined in Scheme 2 of the article should be revised to involve N-alkylation of 1 by IV rather than the C-alkylation, which is followed by condensation of the enamine to afford the correct constitutional isomer. ��

The authors apologize for these mistakes.

Synthesis 2013, 45, 1191.