[Cl:1][C:2]1[CH:20]=[CH:19][C:5]([CH2:6][O:7][C:8]2[CH:9]=[CH:10][C:11]([NH:14]C(=O)OC)=[N:12][CH:13]=2)=[CH:4][CH:3]=1.C(Cl)(Cl)Cl.O>[OH-].[Na+].CO>[NH2:14][C:11]1[CH:10]=[CH:9][C:8]([O:7][CH2:6][C:5]2[CH:19]=[CH:20][C:2]([Cl:1])=[CH:3][CH:4]=2)=[CH:13][N:12]=1A slurry of methyl 5-(4-chlorobenzyloxy)-2-pyridylcarbamate (0.75 g, 2.6 mmol) in 10% sodium hydroxide (20 ml) and methanol (40 ml) is heated to 90° under nitrogen gas. After 1 hour, 10 ml of 10% sodium hydroxide and 10 ml of methanol are added. Heating is continued, and after 2 hours, 10 ml of methanol is added. The reaction is heated under reflux overnight. The reaction is then rotoevaporated, and chloroform and water are added. The residue is extracted with chloroform (4×). The combined chloroform extracts are washed with water until neutral and with brine, dried over calcium sulfate, filtered and rotoevaporated to yield 2-amino-5-(4-chlorobenzyloxy)pyridine.
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