Methyl propiolate → 1,2,3,5-Tetrahydro-1-(2-chloro-5-pyridylmethyl)-8-nitroimidazo[1,2-a]pyridin-5-one
Reaction equation
[N+:1]([CH:4]=[C:5]1[N:9]([CH2:10][C:11]2[CH:12]=[CH:13][C:14]([Cl:17])=[N:15][CH:16]=2)[CH2:8][CH2:7][NH:6]1)([O-:3])=[O:2].C[O:19][C:20](=O)[C:21]#[CH:22]>CO>[Cl:17][C:14]1[CH:13]=[CH:12][C:11]([CH2:10][N:9]2[C:5]3=[C:4]([N+:1]([O-:3])=[O:2])[CH:22]=[CH:21][C:20](=[O:19])[N:6]3[CH2:7][CH2:8]2)=[CH:16][N:15]=1Participants
4
Procedure
A mixed solution of 2-nitromethylene-3-(2-chloro-5-pyridylmethyl) imidazolidine (12.7 g), propiolic acid methyl ester (4.2 g) and methanol (100 ml) was refluxed under heating for about 20 hours. Subsequently methanol was distilled off under reduced pressure, and the residue was refined by a silica-gel column chromatography to give the desired 1,2,3,5-tetrahydro-1-(2-chloro-5-pyridylmethyl)-8-nitroimidazo[1,2-a]pyridin-5-one (8 g).