spiro[3H-chromene-2,1'-cyclobutane]-4-one

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To a solution of 3,4-Dihydro-4-oxo-spiro[2H-1-benzopyran-2,1′-cyclobutane] (Example 3) (10 mmol) in glacial acetic acid (2 ml), conc. H2SO4 (10 mmol) was added at 0° C. and the mixture was stirred for 10 min. A chilled nitrating mixture [prepared from HNO3 (9 mmol) and Conc. H2SO4 (10 mmol)] was then added very slowly and the reaction mixture was allowed to warm up to room temperature and stirred for 5 h. reaction mixture was then quenched with water and the compound was extracted in dichloromethane. Organic layer was separated, dried on anhydrous MgSO4 and concentrated under vacuum. The crude product was then purified by column chromatography to afford the desired compound as a yellow solid. was then added very slowly stirred for 5 h. reaction mixture was then quenched with water the compound was extracted in dichloromethane Organic layer was separated dried on anhydrous MgSO4 concentrated under vacuum The crude product was then purified by column chromatography