464913-11-9

66952-65-6

464913-11-9

Step 7 Synthesis of 3-amino-2-hydroxy-N,N-dimethylbenzamide: 33.5 g of 2-hydroxy-N,N-dimethyl-3-nitrobenzamide was dissolved in 600 mL of ethanol to form a solution. To this solution was added 3.35 g of Pd/C catalyst (suspended in 10 mL of 70 mL of ethanol). The reaction mixture was placed under 2 bar hydrogen atmosphere and the reaction was stirred overnight. The progress of the reaction was monitored by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) (HPLC retention time t = 0.66 min, molecular ion peak M + 181). Upon completion of the reaction, the reaction mixture was filtered through a diatomaceous earth pad to remove the catalyst. The filtrate was concentrated under reduced pressure to give 29 g of brown oily solid, 3-amino-2-hydroxy-N,N-dimethylbenzamide, in 100% yield.