Quinazoline-2,4（1H,3H）-diones are core structural subunits frequently found in many biologically important compounds. The reaction of 2- aminobenzonitrile and CO2, which was frequently studied, only provided N3-unsu...Quinazoline-2,4（1H,3H）-diones are core structural subunits frequently found in many biologically important compounds. The reaction of 2- aminobenzonitrile and CO2, which was frequently studied, only provided N3-unsubstituted quinazoline-2,4（1H,3H）-dione compounds. Herein we report palladium-catalyzed cyclization reactions of o-haloanilines, CO2 and isocyanides to prepare N3-substituted quinazoline-2,4（1H,3H）-diones. Electron-rich o-bromoanilines participated in the cyclization reaction using Cs2CO3 at high temperature, and electron-deficient o-bromoaniline or o-iodoaniline sub- strates conducted the reaction using CsF as base to deliver corresponding quinazoline-2,4（1H,3H）-dione products in good yields.展开更多
基金This work was supported by the Natural Science Foundation of Liaoning Province （20170540156）. X.-B. Lu acknowledges the Program for Changjiang Scholars and Innovative Research Team in University （IRT13008, IRT_17R14）.
文摘Quinazoline-2,4（1H,3H）-diones are core structural subunits frequently found in many biologically important compounds. The reaction of 2- aminobenzonitrile and CO2, which was frequently studied, only provided N3-unsubstituted quinazoline-2,4（1H,3H）-dione compounds. Herein we report palladium-catalyzed cyclization reactions of o-haloanilines, CO2 and isocyanides to prepare N3-substituted quinazoline-2,4（1H,3H）-diones. Electron-rich o-bromoanilines participated in the cyclization reaction using Cs2CO3 at high temperature, and electron-deficient o-bromoaniline or o-iodoaniline sub- strates conducted the reaction using CsF as base to deliver corresponding quinazoline-2,4（1H,3H）-dione products in good yields.
