An unexpected transformation of 2H-chromene-3-carboxaldehydes to coumarin derivatives{,} mediated by NHC{,} is reported.
Vijay Nair, C. R. Sinu, Rejithamol, R., K. C. Seetha Lakshmi, and Eringathodi Suresh, “A novel NHC-catalyzed transformation of 2H-chromene-3-carboxaldehydes to 3-methyl-2H-chromen-2-ones”, Org. Biomol. Chem., vol. 9, pp. 5511-5514, 2011.