161117-88-0

5-Nitropyridin-2-amine (1 eq.), di-tert-butyl dicarbonate (1.2 eq.) and 4-dimethylaminopyridine (0.2 eq.) were added to a reaction vial under nitrogen protection. Dichloromethane was added as solvent at room temperature and the reaction mixture was stirred overnight. Upon completion of the reaction, ethyl acetate was added to the crude product, the precipitate was collected by filtration and washed with ethyl acetate to afford the target product (5-nitropyridin-2-yl)carbamic acid tert-butyl ester. It was analyzed by HPLC-MS (Method A): retention time (Rt) = 2.88 min, m/z of [M + H]+: 240. 80% yield.

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