反应详情

A solution of 5.0 g (30.82 mmol) of 2,2-dimethylchroman (Compound 56) in 50 ml of nitromethane was treated, under nitrogen, with 2.53 g (32.35 mmol) of acetyl chloride followed by 4.4 g (33 mmol) of aluminum chloride. The reaction mixture was stirred at room temperature for 3 hours and then cooled in an ice-bath and treated slowly with 50 ml of 6M HC1. The mixture was diluted with water and extracted with ether. The ether extracts were washed successively with saturated NaHCO3 solution, water and saturated NaCl solution and then dried (MgSO4). The solvent was removed in-vacuo and the resultant residue was purified by flash chromatography (silica; 10% ethyl acetate in hexane) to give the title compound as a white solid. PMR (CDCl3) : & 1.36 (6H, s), 1.84 (2H, t, J~6.8 Hz), 2.54 (3H, s), 2.82 (2H, t, J~6.8 Hz), 6.80 (1H, d, J~8.4 Hz), 7.69-7.76 (2H, m). MS exact mass, m/e 204.1140 (calcd. for C13H16O2, 204.1150).

1. temperaturecooled in an ice-bath
2. additiontreated slowly with 50 ml of 6M HC1
3. extractionextracted with ether
4. washThe ether extracts were washed successively with saturated NaHCO3 solution, water and saturated NaCl solution
5. dry with materialdried (MgSO4)
6. customThe solvent was removed in-vacuo
7. customthe resultant residue was purified by flash chromatography (silica; 10% ethyl acetate in hexane)