CO.[CH3:3][O:4][C:5]([C:7]1[C:12](=[O:13])[CH:11]=[C:10]([CH3:14])O[C:8]=1[C:15]1[CH:20]=[CH:19][C:18]([Cl:21])=[CH:17][CH:16]=1)=[O:6].[CH2:22]([NH2:24])[CH3:23].Cl>O.C(O)(=O)C>[CH2:22]([N:24]1[C:10]([CH3:14])=[CH:11][C:12](=[O:13])[C:7]([C:5]([O:4][CH3:3])=[O:6])=[C:8]1[C:15]1[CH:20]=[CH:19][C:18]([Cl:21])=[CH:17][CH:16]=1)[CH3:23]A 1000 ml flask is fitted with a magnetic stirring bar and a sidearm addition funnel. 500 ml of methanol, 30 ml of glacial acetic acid and 60 g of 3-methoxycarbonyl-6-methyl-2-(4'-chlorophenyl)-4-pyrone are added. 120 ml of 70% aqueous ethylamine is placed in the addition tunnel and added very slowly (4 hr. addition time). 50 ml of water is then added followed by 100 ml of concentrated HCl (cooling required). The reaction mixture is allowed to stand undisturbed for 30 minutes. The bulk of the methanol is then removed in vacuo leaving 46.1 g of methyl 1-ethyl-6-methyl-2-(4'-chlorophenyl)-4-oxonicotinate. mp (methylene chloride/ether)=217°-219° C.
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