Iron-Catalyzed [2+1+2+1] Annulation of Amines and N,N-Dimethyl Enaminones using N,N-dimethylaminoethanol as One Carbon Synthon for the Synthesis of 1,4-Dihydropyridines.

A simple and efficient method for the synthesis of 1,4-dihydropyridines from amines, N,N-dimethyl enaminone and N,N-dimethylaminoethanol in a four-component [2+1+2+1] annulation catalyzed by FeCl3 has been established, where N,N-dimethylaminoethanol was applied as a methine source. The procedure was executed smoothly, resulting in the synthesis of a wide range of 1,4-dihydropyridines with moderate to good yields. Additionally, these fluorophores exhibited good photophysical characteristics.