Sodium Hydroxide → Thieno[3,4-c]pyridine-6-carboxylic acid

Reaktionsgleichung

[CH:1]1[S:2][CH:3]=[C:4]2[C:9]=1[CH:8]=[C:7]([C:10]([O:12]C)=[O:11])[N:6]=[CH:5]2.[OH-].[Na+]>CO.O>[CH:1]1[S:2][CH:3]=[C:4]2[C:9]=1[CH:8]=[C:7]([C:10]([OH:12])=[O:11])[N:6]=[CH:5]2

Komponenten

Versuchsvorschrift

Methyl thieno[3,4-c]pyridine-6-carboxylate (250 mg, 1.3 mmol) is dissolved in MeOH (7 ml) and water (1 ml). 2M NaOH (0.72 ml, 1.43 mmol) is added drop-wise. The reaction is stirred overnight at rt and is monitored by TLC. The volatiles are removed in vacuo and the residue is dissolved in water (2 ml). 10% HCl is used to adjust the pH to 3, and the reaction again stirred overnight at rt. The aqueous solution is extracted repeatedly with EtOAc (20×10 ml). The combined organics are dried over MgSO4, filtered, and concentrated to a yellow solid. The amount of isolated product via extraction is minimal (67 mg), so the aqueous layer is concentrated and found to contain the majority of product. Extraction of the solid aqueous residue with EtOAc provided 225 mg (97%) of thieno[3,4-c]pyridine-6-carboxylic acid as a yellow solid. MS (EI) m/z: 179 (M+).