1093759-59-1

General procedure for the synthesis of N-Boc-4-methoxyindole from 4-methoxyindole and di-tert-butyl dicarbonate: 1.6 g of 4-methoxyindole was dissolved in 20 mL of acetonitrile, followed by the addition of 2.6 g of di-tert-butyl dicarbonate and 0.03 g of 4-dimethylaminopyridine (DMAP). The reaction mixture was stirred at room temperature overnight. After completion of the reaction, the mixture was poured into a pH 2 buffer solution and extracted with ethyl acetate (EtOAc). The organic phase was washed with saturated sodium chloride (NaCl) solution and dried over anhydrous magnesium sulfate (MgSO4). After concentration under reduced pressure to remove the solvent, the residue was purified by silica gel column chromatography using a gradient elution of cyclohexane/ethyl acetate (98/2 v/v to 95/5 v/v). 2.4 g of N-Boc-4-methoxyindole was finally obtained.

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