反应详情

温度

2.5 °C

To a solution of 5-methoxy-[1,2,5]triazepane-1-carboxylic acid ethyl ester hydrochloride salt (1.33 g, 4.84 mmol), triethylamine (1.68 ml, 1.22 g, 12.07 mmol) and a catalytic amount of 4-dimethylaminopyridine in tetrahydrofuran (20 ml) at 0-5° C. was added a solution of (2,5-dimethyl-phenyl)-acetyl chloride (0.93 g, 5.09 mmol) in tetrahydrofuran (5 ml) dropwise. The suspension was stirred at 0-5° C. for one hour, and at room temperature for 4 hours. The solvent was evaporated, the residue diluted with ethyl acetate (50 ml) and water (20 ml), the layers separated and the aqueous phase extracted with ethyl acetate (2×25 ml). The combined organic layers were washed with water (2×20 ml) and brine (20 ml), dried over sodium sulfate and concentrated. The residue was purified by chromatography on silica gel (cyclohexane/ethyl acetate 2:1). Yield: 1.1 g of 2-[2-(2,5-dimethyl-phenyl)-acetyl]-5-methoxy-[1,2,5]triazepane-1-carboxylic acid ethyl ester (compound P3.3) as a viscous oil. 1H-NMR (400 MHz, CD3OD): δ 1.14-1.39 (br m, 3H), 2.18 (s, 3H), 2.26 (s, 3H), 2.83-3.09 (br m, 4H), 3.13-3.32 (br m, 2H), 3.48 (s, 3H), 3.62 (br s, 2H), 3.78-4.32 (br m, overlapping signals, total 4H), 6.91 (s, 1H), 6.95 (d, J=7.8 Hz, 1H), 7.03 (d, J=7.8 Hz, 1H) ppm.

1. waitat room temperature for 4 hours
2. customThe solvent was evaporated
3. additionthe residue diluted with ethyl acetate (50 ml) and water (20 ml)
4. customthe layers separated
5. extractionthe aqueous phase extracted with ethyl acetate (2×25 ml)
6. washThe combined organic layers were washed with water (2×20 ml) and brine (20 ml)
7. dry with materialdried over sodium sulfate
8. concentrationconcentrated
9. customThe residue was purified by chromatography on silica gel (cyclohexane/ethyl acetate 2:1)