A Convenient Method for the Synthesis of Chromeno[4,3-b]pyridines Via Three-component Reaction

Comb Chem High Throughput Screen. 2018;21(5):344-348. doi: 10.2174/1386207321666180524110635.

Abstract

Aim and objective: The importance of Chromeno[4,3-b]pyridines in bioactive compounds, highlighted the ongoing research on developing novel methods for the construction of this heterocyclic scaffold. Regarding the advantageous features of multi-component reactions in organic synthesis, we will try to synthesize pyridocoumarins through this method.

Materials and methods: Chromeno[4,3-b]pyridines were conveniently prepared from a threecomponent condensation reaction between 4-hydroxy coumarin, ammonia and ethyl 2,4-dioxo-4- arylbutanoates in refluxing n-propanol. The synthesized compounds were characterized by NMR, IR and Mass spectroscopy.

Results: The reaction proceeded through an in situ formed 4-amino coumarin, affording eight new target compounds in good yields.

Conclusion: This method introduce a novel approach to ethyl 4-aryl-5-oxo-5H-chromeno[4,3- b]pyridine-2-carboxylate derivatives and allow organic chemists to prepare 4-aminocoumarin in reaction medium.

Keywords: 4-amino coumarin; 4-hydroxy coumarin; Pyridocoumarin; ammonia; multi-component reaction; one-pot..

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aminocoumarins / chemical synthesis
  • Ammonia / chemistry
  • Benzopyrans / chemical synthesis*
  • Butyric Acid / chemistry
  • Molecular Structure
  • Pyridines / chemical synthesis*
  • Solvents / chemistry
  • Temperature

Substances

  • Aminocoumarins
  • Benzopyrans
  • Pyridines
  • Solvents
  • Butyric Acid
  • Ammonia