Efficient synthesis of new functionalized 2-(alkylamino)-3-nitro-4-(aryl)-4H-benzo[g]chromene-5,10-dione.

Structurally diverse benzo[g]chromenes were conveniently synthesized by one-pot, multi-component reaction of N-alkyl-1-(methylthio)-2-nitroethenamine (derived from the reaction of nitroketene dithioacetal with various amines), aromatic aldehydes and 2-hydroxy-1,4-naphthoquinone in CHCN at room temperature within 10-25 min, without any catalyst. The notable advantages of the protocol are mild reaction conditions, absence of catalyst, very short reaction time, simple purification process involving no chromatographic process, compatibility with various functional groups and excellent product yields.