Efficient synthesis of tetrahydro-1H-pyrazolo3,4-bpyridines based on the recyclization of N-arylitaconimides with aminopyrazoles

摘要

New polyfunctional hydrogenated pyrazolo3,4-bpyridines were obtained by the chemoselective reaction between N-aryl-itaconimides and 5-aminopyrazoles. The transformation is the cascade reaction including Michael addition at the active double bond of the itaconimide followed by the intramolecular transamidation and recyclization.