Methyl iodide → 1-Bromo-4-(2-methoxypropan-2-yl)benzene

Beteiligte Stoffe

Reaktionsschritte

A mixture of 6.87 g of ethyl 4-bromobenzoate (10) was allowed to react with 64 mL (1.4 M in toluene) of methyl magnesium bromide in THF at −40° C. for 1 hour, and the reaction mixture was gradually warmed to 0° C. The reaction was quenched with saturated aqueous ammonium chloride solution and the resultant mixture was extracted with ethyl acetate. The organic layer was washed with brine, was dried over magnesium sulfate, was filtered, and the solvent was removed in vacuo. Purification by silica gel chromatography (50:1 to 10:1 hexanes-ethyl acetate) afforded 6.44 g (99% yield) of 2-(4-bromophenyl)propan-2-o1; MS (AP/CI) observed: 199.1 (M+H−H2O)+, 100%; 213.1, 215.1 (M−H)−, 60%, 80%. 2-(4-Bromophenyl)propan-2-o1 (1.77 g) and iodomethane (1.16 g) in THF (100 mL) were treated with sodium hydride, 60% in mineral oil (328 mg). After stirring for 24 h at room temperature, the reaction mixture was quenched with dilute aqueous hydrochloric acid, was extracted with ethyl acetate, and the organic layer was washed with brine, was dried over magnesium sulfate, was filtered, and the solvent was removed in vacuo. The resultant oil was purified by silica gel chromatography (200:1 hexanes-ethylacetate) to afford 0.5 g of 1-bromo-4-(1-methoxy-1-methyl-ethyl)-benzene; 13C NMR (400 MHz, CDCl3) δ 145.35, 131.53, 127.91, 121.00, 50.90, 28.60.

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