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The general procedure for the synthesis of 1-(3-amino-4-(benzyloxy)-2-hydroxy-3-nitrophenyl)ethanone from 1-(4-(benzyloxy)-2-hydroxy-3-nitrophenyl)ethanone was carried out as follows: zinc powder (5.50 g, 84.1 mmol) was added batchwise to 1-(4-(benzyloxy)-2-hydroxy-3-nitrophenyl)ethanone (5.50 g, 19.2 mmol) in a suspension in acetic acid (55 mL), and the reaction was carried out with an ice bath to control the internal temperature not to exceed 40 °C for 15 min. The reaction mixture was then warmed to room temperature and stirring was continued for 2 hours. Upon completion of the reaction, the mixture was filtered through diatomaceous earth and the filter cake was washed with acetic acid. The filtrate was slowly poured into an ice-water mixture (500 mL) and a solid was precipitated. The precipitate was collected by filtration, washed with water and dried under vacuum at 40 °C to afford the target product 1-(3-amino-4-(benzyloxy)-2-hydroxyphenyl)ethanone (4.80 g, 18.7 mmol, 97% yield) as a light brown solid. The mass spectrum (ESI+) showed the molecular ion peak m/z 258 [M + H]+.

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