[CH:1]([C:3]1[N:4]=[C:5]([C:8]2[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=2)[NH:6][CH:7]=1)=[O:2].[OH-].[K+].S(OC)(O[CH3:20])(=O)=O>C(Cl)Cl.[Br-].C([N+](CCCC)(CCCC)CCCC)CCC>[CH3:20][N:4]1[C:3]([CH:1]=[O:2])=[CH:7][N:6]=[C:5]1[C:8]1[CH:9]=[CH:10][CH:11]=[CH:12][CH:13]=1To a solution of 4-formyl-2-phenylimidazole (100 mg, 0.58 mmol) in CH2Cl2 (2 mL) was added aqueous KOH (2 mL of a 30% solution), followed by dimethyl sulfate (66 μL, 0.70 mmol), and tetrabutylammonium bromide (10 mg; 0.039 mmol). The reaction mixture was stirred overnight at RT and then was partitioned between ETOAc and water; the organic phase was washed with brine and then concentrated in vacuo. The residue was chromatographed (SiO2; continuous gradient from 1:1 hexane:EtOAc to 100% EtOAc) to give 1-methyl-2-phenyl-imidazole-5-carboxaldehyde as a solid (35 mg; 32%; 1st eluted fraction; Part A compound) and Part B compound
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