[O:1]1[C:5]2[C:6]([C:10]([OH:12])=O)=[CH:7][CH:8]=[CH:9][C:4]=2[CH2:3][CH2:2]1.O[N:14]1C2C=CC=CC=2N=N1.Cl.CN(C)CCCN=C=NCC.N.CO>C(Cl)Cl.CN(C=O)C.C(OCC)(=O)C>[O:1]1[C:5]2[C:6]([C:10]([NH2:14])=[O:12])=[CH:7][CH:8]=[CH:9][C:4]=2[CH2:3][CH2:2]12,3-Dihydrobenzofuran-7-carboxylic acid (15.0 g, 91 mmol) was dissolved in DCM (150 ml) and DMF (150 ml). 1-Hydroxybenzotriazole (12.3 g, 91 mmol) was added. The solution was cooled to 0° C. N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (17.5 g, 91 mmol) was added. The reaction mixture was stirred for 20 min at 0° C. A 1 N solution of ammonia in methanol (200 ml, 200 mmol) was added. The reaction mixture was stirred for 16 hours, while it was warming up to room temperature. It was diluted with ethyl acetate (200 ml) and washed with a 10% aqueous sodium hydrogensulphate solution. The aqueous phase was extracted with ethyl acetate (2×100 ml). The combined organic layers were washed with a saturated aqueous solution of sodium hydrogen carbonate (400 ml) and dried over magnesium sulphate. The solvent was removed in vacuo. The remaining crystals were washed with ethyl acetate (3×100 ml) and dried in vacuo to give 5.21 g of 2,3-dihydrobenzofuran-7-carboxylic acid amide.
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