反应详情

2-Benzoylbenzoic acid (0.341 g, 1.51 mmol) was taken up in a 2M solution of oxalyl chloride in methylene chloride (1.5 mL, 3.0 mmol). One drop of N,N-dimethylfornamide was added and the frothy mixture was stirred overnight and concentrated. A solution of the crude 2-benzoylbenzoyl chloride in methylene chloride (4 mL) followed by triethylamine (0.25 mL, 1.8 mmol) was added to the product of step 2 (0.220 g, 0.502 mmol). The mixture was heated at reflux for 2 hours and concentrated. The residue was taken up in 5:1 methanol/1 N aqueous lithium hydroxide (12 mL) and stirred for 1 hour. The reaction was again concentrated and the residue was partitioned between ethyl acetate and aqueous sodium bicarbonate solution. The organic layer was dried (sodium sulfate) and concentrated to afford a foamy amber solid. Flash chromatography over silica (methylene chloride/methanol) provided 0.229 g (71%) of product as a foamy pale amber solid: 1H NMR (CDCl3) δ 7.91-6.92 (m, 26H), 6.54-6.39 (m, 1H), 6.34-6.06 (m, 1H), 4.83-4.31 (m, 2H), 3.97-2.82 (m, 3H), 2.70-2.39 (m, 3H), 2.35-2.09 (m, 2H) ppm. MS (ESI) m/z 648 (M+H+).

1. additionOne drop of N,N-dimethylfornamide was added
2. concentrationconcentrated
3. temperatureThe mixture was heated
4. temperatureat reflux for 2 hours
5. concentrationconcentrated
6. stirringstirred for 1 hour
7. concentrationThe reaction was again concentrated
8. customthe residue was partitioned between ethyl acetate and aqueous sodium bicarbonate solution
9. dry with materialThe organic layer was dried (sodium sulfate)
10. concentrationconcentrated
11. customto afford a foamy amber solid