反应详情

Potassium nitrate (8.6 g) was added portionwise over 1/2 h to a solution of 7-amino-2,3-dihydrobenzofuran (D3) (10 g) in concentrated sulphuric acid (75 ml) at 5°-10° C. The resulting solution was stirred for a further 2 h, then added to ice, basified with 40% NaOH, and extracted into ethyl acetate. The organic phase was dried (Na2SO4) and the solvent evaporated under reduced pressure to give the title compound (10.1 g, 76%) as a red/brown foam.

1. additionadded to ice
2. extractionextracted into ethyl acetate
3. dry with materialThe organic phase was dried (Na2SO4)
4. customthe solvent evaporated under reduced pressure