A facile approach to 6-amino-2H-pyrano[2,3-g]isoquinolin-2-ones via a sequential Sonogashira coupling of 6-cyanoumbelliferone triflate and annulations with amines

Abstract

Palladium-catalyzed synthesis of 2H-pyrano[2,3-g]isoquinolinones have been described from easily accessible precursor 6-cyanoumbelliferone triflate via sequential of Sonogashira coupling and the following annulations with several primary alkylamines under basic conditions The so obtained 6-propargylamino-2H-pyrano[2,3-g]isoquinolinones were involved in the CuAAC reaction with 2-azidobenzoic acid for obtaining 2H-pyrano[2,3-g]isoquinoline-benzoic acid hybrid compounds containing a 1,2,3-triazole linker.

Graphical Abstract

Keywords:

• Alkynes
• Click chemistry
• coumarin
• heterocyclization
• Sonogashira reaction

Acknowledgments

Authors would like to acknowledge the Multi-Access Chemical Research Service Center SB RAS for spectral and analytical measurements.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

Financial support from the Russian Science Foundation [Grants No 17-73-10099, 18-13-00361] is acknowledged.