[Cl:1][C:2]1[CH:7]=[C:6]([Cl:8])[CH:5]=[CH:4][C:3]=1[C:9]1[N:10]([C:20]2[CH:25]=[CH:24][C:23]([O:26][CH3:27])=[CH:22][CH:21]=2)[C:11]([CH3:19])=[C:12]([C:14]([O:16]CC)=[O:15])[N:13]=1.[Li+].[OH-].O.Cl>C1COCC1.C(OC(=O)C)C>[Cl:1][C:2]1[CH:7]=[C:6]([Cl:8])[CH:5]=[CH:4][C:3]=1[C:9]1[N:10]([C:20]2[CH:21]=[CH:22][C:23]([O:26][CH3:27])=[CH:24][CH:25]=2)[C:11]([CH3:19])=[C:12]([C:14]([OH:16])=[O:15])[N:13]=1Part B: To a stirred solution of ethyl 2-(2,4-dichlorophenyl)-5-methyl-1-(4-methoxyphenyl)-1H-imidazole-4-carboxylate (8.00 gram, 0.0198 mol) in THF (80 mL) is added LiOH (0.59 gram, 2 molar equivalents) and water (80 mL). The resulting mixture is stirred for 16 hours at 80° C. After cooling to room temperature, HCl (2N solution, 12.3 mL) is added to give an oily precipitate. After addition of water and extraction with ethylacetate, the ethylacetate layer is collected, dried over Na2SO4, filtered and concentrated in vacuo. The residue is crystallised from diisopropyl ether and dried to give 2-(2,4-dichlorophenyl)-5-methyl-1-(4-methoxyphenyl)-1H-imidazole-4-carboxylic acid (4.04 gram, 87% yield) as a pale grey solid. Melting point: 189–191° C.
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