[Br:1]N1C(=O)NC(=O)N(Br)C1=O.[CH:12]1([C:15]2[CH:24]=[CH:23][C:18]([C:19]([O:21][CH3:22])=[O:20])=[C:17]([O:25][CH2:26][CH3:27])[CH:16]=2)[CH2:14][CH2:13]1.S([O-])([O-])(=O)=S.[Na+].[Na+]>CN(C=O)C>[Br:1][C:24]1[C:15]([CH:12]2[CH2:14][CH2:13]2)=[CH:16][C:17]([O:25][CH2:26][CH3:27])=[C:18]([CH:23]=1)[C:19]([O:21][CH3:22])=[O:20]Dibromoisocyanuric acid (2.54 g) was added at room temperature to a DMF (60 mL) solution of methyl 4-cyclopropyl-2-ethoxybenzoate (3.25 g), and the mixture was stirred at 90° C. for 1 hour in a nitrogen atmosphere. Dibromoisocyanuric acid (423 mg) was added to the reaction mixture, and the mixture was stirred at 90° C. for 30 minutes in a nitrogen atmosphere. An aqueous sodium thiosulfate solution was added to the reaction mixture at room temperature, followed by extraction with ethyl acetate. The obtained organic layer was washed with water and saturated saline in this order and dried over anhydrous magnesium sulfate, and then, the solvent was distilled off under reduced pressure. The obtained residue was purified by silica gel column chromatography (hexane/ethyl acetate) to obtain the title compound (4.08 g).
Loading…
