Hydrochloric Acid → 6-Methanesulfonamidopyridine-3-carboxylic acid

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Reaction Steps

To a solution of methyl 6-aminonicotinate (1.0 g, 6.57 mmol) in CH2Cl2 (50 mL) with TEA (0.96 mL, 6.90 mmol) cooled in an ice bath is added MsCl (0.54 mL, 6.90 mmol) slowly. The crude is allowed to stir at room temperature for 2 hrs. The crude is then concentrated. The crude is dissolved in MeOH (20 mL) and to the crude is added 1 N NaOH (30 mL, 30 mmol). The crude is stirred at room temperature for 18 hrs. The crude is quenched with 1N HCl (32 mL, 32 mmol). The crude is concentrated to remove MeOH and some water is removed as well. The crude is diluted in CH2Cl2 and basified with 1 N NaOH (30 mL). The aq. layer is extracted with CH2Cl2. The aq. layer is acidified with concentrated HCl to bring the PH to 1 via PH paper indicator. The crude is diluted in EtOAc and the aq. layer is extracted with EtOAc. The combined organic layer is washed with brine, dried over MgSO4, filtered, and concentrated to give 6-(methylsulfonamido)nicotinic acid (421 mg) as a yellow solid. HPLC retention time=0.40 minutes (condition D); MS (m+1)=217.2.

Provenance & Evidence