[Cl:1][C:2]1[N:7]=[C:6]([C:8]([OH:10])=[O:9])[CH:5]=[CH:4][CH:3]=1.[CH3:11]N(C=O)C.C(Cl)(=O)C(Cl)=O.CO>C(Cl)Cl>[Cl:1][C:2]1[N:7]=[C:6]([C:8]([O:10][CH3:11])=[O:9])[CH:5]=[CH:4][CH:3]=16-Chloropyridine-2-carboxylic acid (15.0 g, 0.11 mol) was dissolved in DCM (300 mL) and DMF (1.5 mL) and oxalyl chloride (27.4 g, 0.22 mol) was added dropwise over 10 min. The reaction mixture was stirred for 1 h, MeOH (50 mL) was added dropwise over 5 min and the reaction mixture was stirred for 1.5 h. The solvents were removed in vacuo and the residue azeotroped with DCM (2×150 mL) to give the crude title compound (16.5 g, 100%) as a green solid. LCMS (ES+): 154.5 [MH]+.
Wird geladen…