Potassium Carbonate → 1-Bromo-5-ethyl-2,4-dimethoxybenzene

Beteiligte Stoffe

Reaktionsschritte

A solution of tetrabutyl ammonium tribromide (15.4 g, 31.8 mmol) in CHCl3 (100 mL) was added to a stirred solution of 4-ethyl resorcinol (4 g, 29 mmol) dissolved in CHCl3 (50 mL). The reaction mixture was stirred for 2 hours and then quenched with 5% solution of sodium thiosulfate (30 mL). The biphasic mixture was stirred for 30 mins and then the layers were separated. The organic layer was washed with 1 N HCl, brine, dried over Na2SO4 and concentrated to yellow oil. The oil was dissolved in DMF (60 mL) and treated with K2CO3 (12.7 g, 92 mmol), followed by methyl iodie (2.9 mL, 46 mmol). The mixture was stirred for 15 hours and then partitioned between H2O and EtOAc. The organic layers were washed with 1 N HCl, brine, dried over Na2SO4 and concentrated to a dark red oil. Purification by flash column chromatography (0% to 10% EtOAc in hexanes) gave the product as a yellow oil (2.8 g, 39%). 1H NMR (400 MHz, CDCl3): δ 1.15 (t, J=7.6 Hz, 3 H), 2.54 (q, J=7.6 Hz, 2 H), 3.83 (s, 3 H), 3.89 (s, 3 H), 6.46 (s, 1 H), 7.26 (s, 1 H).

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