Facile one pot synthesis of furo/pyrano [3,2-c]-1, 2, 3, 4-tetrahydroquinolines from nitro benzenes and 2,3-dihydrofuran or 3,4-dihydro-2H-pyran in methanol catalyzed by SnCl2.2H2O

B.C.Goudarshivannanavar, H.C.K

Abstract

Various nitro benzenes react immediately with 2,3-dihydrofuran or 3,4-dihydro-2H-pyran in one pot to produce 1,2,3,4-tetrahydrofuro/pyrano quinolines in presence of SnCl2.2H2O as reducing agent and catalyst at reflux temperature in methanol.SnCl2.2H2O was found to reduce -NO2 to -NH2 efficiently, also facilitate imino Diels- Alder reaction of imine formed by the reaction between aryl amines,whichwas generated during reduction of aryl nitro compounds and with 2,3-dihydrofuran or 3,4-dihydro-2H-pyran.