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

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.