反应详情

N-(heptan-4-yl)-3,4-dihydroxybenzamide (example 18a) (0.29 mmol, 75 mg) was dissolved in dry acetone with 6 eq excess (242 mg) of potassium carbonate then 1.2 eq excess (36 μl) of propynoic acid ethyl ester was added and a mixture was refluxed for 24 h. The solvent was evaporated and a solid was dissolved in dichloromethane and extracted with 10% NaHCO3 and water. The crude product was purified by chromatography on silica gel to give 72 mg of desired product (71%). 1H NMR (500 MHz, CDCl3): δ 0.91-0.94 (t, 6H), 1.23-1.30 (m, 4H), 1.37-1.41 (4H), 2.97-2.98 (d, 2H), 3.70-3.74 (dd, 2H), 4.12-4.17 (m, 1H), 4.2-4.24 (m, 3H), 5.61-5.64 (d, 1H), 6.58-6.60 (t, 1H), 6.79-6.81 (d, 1H), 7.23 (s, 1H), 7.60-7.85 (b, 1H). MS (M+H, 350.1).

1. temperaturea mixture was refluxed for 24 h
2. customThe solvent was evaporated
3. dissolutiona solid was dissolved in dichloromethane
4. extractionextracted with 10% NaHCO3 and water
5. customThe crude product was purified by chromatography on silica gel