Chloroacetaldehyde → Methyl imidazo(1,2-a)pyridine-6-carboxylate
Reaction equation
Cl[CH2:2][CH:3]=O.[CH3:5][O:6][C:7](=[O:15])[C:8]1[CH:13]=[CH:12][C:11]([NH2:14])=[N:10][CH:9]=1>C(O)C>[CH3:5][O:6][C:7]([C:8]1[CH:13]=[CH:12][C:11]2[N:10]([CH:2]=[CH:3][N:14]=2)[CH:9]=1)=[O:15]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
To a solution of 50% aq. chloroacetaldehyde (1.1 eq, 36 mmol, 4.6 ml) in ethanol (120 ml) is added 6-amino-nicotinic acid methyl ester (1 eq, 33 mmol, 5 g) at room temperature. The reaction mixture is heated at reflux for 18 hours. The solvent is removed in vacuo and the crude product is dissolved in water (400 ml). The aqueous solution is treated with sodium bicarbonate to pH=8 and extracted with DCM (3×250 ml). The organic layer is dried (MgSO4) and evaporated to give the title compound as a beige solid.