反应详情

A solution of 2-chloro-5-hydroxybenzoic acid (1.0 g, 5.8 mmol) in DCM (10 ml) was treated with triethylamine (2.5 eq, 2.0 ml, 14.5 mmol) and 2,2-dimethylpropanoyl chloride (2.0 eq, 1.43 ml, 11.6 mmol). Mixture stirred at room temperature for 2 hours. A solution of methyl 4-(aminomethyl)benzoate hydrochloride (1.5 eq, 1.75 g, 8.7 mmol) and triethylamine (2.0 eq, 1.6 ml, 11.6 mmol) in DCM (10 ml) was then added and the mixture stirred at room temperature for another 2 hours. The mixture was diluted with DCM (300 ml) and aqueous sodium bicarbonate (100 ml), layers separated and aqueous layer extracted again with DCM (200 ml). Organic layers combined, washed with brine, dried over magnesium sulphate and evaporated. Residue purified by column chromatography (Biotage SP4) eluting with 0-30% EtOAc in Hex to give the title compound as a white solid. MS (ES+) m/z 404 [M+H]+ (C21H2235ClNO5). 1H-NMR (400 MHz, d6-DMSO) δ 1.30 (9H, s), 3.85 (3H, s), 4.51 (2H, d, J 6), 7.24 (1H, dd, J 8.8, J 2.8), 7.29 (1H, d, J 2.8), 7.51 (2H, d, J 8.8), 7.56 (2H, d, J 8.4), 7.95 (2H, m).

1. stirringthe mixture stirred at room temperature for another 2 hours
2. customseparated
3. extractionaqueous layer extracted again with DCM (200 ml)
4. washwashed with brine
5. dry with materialdried over magnesium sulphate
6. customevaporated
7. customResidue purified by column chromatography (Biotage SP4)
8. washeluting with 0-30% EtOAc in Hex