[OH2:1].Cl[C:3]1[C:13]([N+:14]([O-:16])=[O:15])=[CH:12][CH:11]=[C:10]([Cl:17])[C:4]=1[C:5]([N:7]([CH3:9])[CH3:8])=[O:6].[H-].[Na+].Cl>O1CCCC1>[Cl:17][C:10]1[C:4]([C:5]([N:7]([CH3:9])[CH3:8])=[O:6])=[C:3]([OH:1])[C:13]([N+:14]([O-:16])=[O:15])=[CH:12][CH:11]=13.2 ml (177.6 mmol, 4.2 eq) of water and 11.04 g (41.96 mmol; 1.0 eq) of 2,6-dichloro-N,N-dimethyl-3-nitrobenzamide (41.96 mmol; 1.00 eq.) in solution in 130.00 ml of tetrahydrofuran were added to a suspension of 7.16 g (179.01 mmol; 4.3 eq) sodium hydride in 250 ml of tetrahydrofuran cooled to 0° C. After 10 min, the reaction medium was stirred at ambient temperature for 19 hours. The reaction medium was hydrolyzed with a 1 N aqueous hydrochloric acid solution and extracted with ethyl acetate. The organic phase was washed with a 1 N aqueous hydrochloric acid solution, dried over anhydrous sodium sulfate, filtered and concentrated. The residue (11.82 g) was chromatographed on silica gel (300 g prepacked column, eluent heptane/ethyl acetate from 40% to 80% of ethyl acetate, 150 ml/min). 6.10 g of 6-chloro-2-hydroxy-N,N-dimethyl-3-nitrobenzamide were obtained in the form of a yellow solid. Yield=59%.
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