Microwave-assisted liquid-phase combinatorial synthesis of quinoxaline-2-ones is reported. Immobilized aryl fluoride was aminated via ipso-fluoro displacement and then reduced the adjacent nitro group to give polymer bound o-phenylenediamine in the microwave oven. Spontaneous condensation and intramolecular cyclization of diamines with chloroacetyl chloride under microwave irradiation resulted in the formation of quinoxaline-2-ones as a combinatorial scaffold. Analytically pure target molecules were isolated after cleavage of the polymer support. All reactions involved were performed completely within a few minutes under microwave exposure.
- Combinatorial synthesis