[Br-:1].[K+].C1OCCOCCOCCOCCOCCOC1.ClC1C=C(C=CC=1)C(OO)=O.[CH:32]([C:35]1[CH:40]=[CH:39][CH:38]=[CH:37][C:36]=1[O:41][CH3:42])([CH3:34])[CH3:33]>C(Cl)Cl>[Br:1][C:39]1[CH:38]=[CH:37][C:36]([O:41][CH3:42])=[C:35]([CH:32]([CH3:34])[CH3:33])[CH:40]=1
To a suspension of potassium bromide (18.8 g, 157.7 mmol) in 400 mL of methylene chloride at 0° C. were added 18-Crown-6 (2.08 g, 7.88 mmol), 3-chloroperoxy benzoic acid (27.2 g, 157.7 mmol) and 2-isopropylanisole (12.0 g, 78.8 mmol). After stirring for 3 hours at 0° C., the reaction mixture was poured into ice water (500 mL), and stirred for 30 minutes. The organic layer was separated, washed with saturated NaHCO3 solution (400 mL), followed by water (300 mL), and dried (MgSO4). The solvent was evaporated to give an oil, which was purified by flash column chromatography (silica gel, 98:2 hexane/ethylacetate) to give 13 g (56.7 mmol, 72%) of 4-bromo-2-isopropylanisole (3) as an oil; 1HNMR (CDCl3) δ 1.2 (d, 6H), 3.3 (heptet, 1H), 6.7 (d, 1H), 6.84 (d, 1H), 7.29 (s, 1H).
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