反应详情

To a −78C solution of LDA (generated from 8 ml of 2.5 M nBuLi and 2.1 ml of diisopropylamine) in THF (120 ml) was added dropwise, over 80 min, a solution a 4′-bromoacetophenone (2.98 g, 14.97 mmol) in THF (45 ml). The mixture continued to stir at −78C for 1 h, followed by addition of 1-(cyclopropylcarbonyl)-1H-1,2,3-benzotriazole (2.56 g, 13.65 mmol) in THF (45 ml). The mixture was warmed to rt overnight. The yellow mixture was poured into water and extracted with Et2O (2×300 ml). The combined organic phases were washed with water, dried with MgSO4, and concentrated in vacuo. The crude material was purified by flash chromatography (CH2Cl2/hexanes, 10:90 to 30:70) to yield 1-(4-bromophenyl)-3-cyclopropyl-1,3-propanedione as an orange solid (1.60 g, 44%).

1. extractionextracted with Et2O (2×300 ml)
2. washThe combined organic phases were washed with water
3. dry with materialdried with MgSO4
4. concentrationconcentrated in vacuo
5. customThe crude material was purified by flash chromatography (CH2Cl2/hexanes, 10:90 to 30:70)