Hydrochloric Acid → HCID 21886421, compound

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Reaction Steps

4-Bromo-5-methyl-3-nitrobenzoic acid methyl ester ((Example 294: step a (11.6 g, 42.3 mmol) was dissolved in MeOH (400 mL) at rt and 2N NaOH (43 mL) was added dropwise over 30 min via addition funnel. The solution was stirred for 12 hr during which, precipitate appeared, and sm disappeared (TLC shows only baseline spot in 30% EtOAc). The pH was adjusted to ˜2 with conc HCl and the methanol was removed in vacuo. EtOAc (300 mL) was added to the aqueous slurry and the layers were separated. The aqueous layer was extracted with EtOAc (2×50 mL) and then discarded. TLC analysis of the combined organic extracts showed two products (40% EtOAc in Hexanes, 4% AcOH). The combined organic extracts were washed with a 3:1 solution of 0.5N NaH2PO4/0.5N NaOAc (˜30×50 mL portions) until removal of the o-nitrobenzoic acid (lower spot on TLC, 40% EtOAc in Hex, 4% AcOH) was complete. The organic layer was then washed with brine and dried over sodium sulfate. Concentration of the solution yielded 5.4 g (47%) of a white solid. 1H NMR (CD3OD) δ 8.10 (m, 2H), 2.54 (s, 3H).

Provenance & Evidence