N<sub>2</sub>H<sub>4</sub>–H<sub>2</sub>O Enabled Umpolung Cyclization of <i>o</i>-Nitro Chalcones for the Construction of Quinoline <i>N</i>-Oxides
Guan Zhang, Kai Yang, Shihui Wang, Qiang Feng, Qiuling Song
Abstract
Umpolung is a unique strategy which converts the property of an atom into the opposite one. An efficient and general method for the construction of quinoline N-oxides via umpolung of carbonyl groups was developed from ortho-nitro chalcones and hydrazine in basic conditions. The strategy is transition-metal free and has good functional group tolerance, environmental friendliness, as well as mild reaction conditions with nitrogen gas as the byproduct.
Topics & Concepts
UmpolungChemistryQuinolineNitroHydrazine (antidepressant)NitrogenNitrogen atomFunctional groupMedicinal chemistryCombinatorial chemistryGroup (periodic table)Organic chemistryCatalysisNucleophilePolymerAlkylChromatographyN-Heterocyclic Carbenes in Organic and Inorganic ChemistrySynthesis and Biological EvaluationCatalytic C–H Functionalization Methods