Synthesis of 2-Amino-4-(2-hydroxynaphthyl)-4H-chromene-3-carbonitriles by Michael Addition and Their Transformation into New Pentacyclic Compounds

Abstract

2-Amino-4-(2-hydroxynaphthyl)-4H-chromene-3-carbonitriles were synthesized by Michael addition of various 3-cyanoiminocoumarins and β-naphthol in good yield. The heterocyclization of these materials in an acidic medium leads new heterocyclic compounds, which have not previously been described, in moderate to good yields and good selectivity. The synthesized compounds were characterized by infrared, ¹H NMR, ¹³C NMR, two-dimensional NMR, and elemental analysis.

GRAPHICAL ABSTRACT

Keywords:

• 2-Amino-4H-chromene
• heterocyclization
• iminocoumarin
• Michael addition
• β-naphthol

Notes

^a Isolated yield.

^a Isolated yield.