Benzyl Bromide → 1-Benzyl-2,5-dimethoxy-3,4,6-trimethylbenzene

Beteiligte Stoffe

Reaktionsschritte

A 24.1 ml (38.6 mmole) of n-butyllithium.hexane solution was added dropwise to 10.0 g (38.6 mmole) of 1-bromo-2,5-dimethoxy-3,4,6-trimethylbenzene dissolved in anhydrous tetrahydrofuran (100 ml), under an atmosphere of argon at -40° C. over the period of 10 minutes, followed by stirring for another 20 minutes. Then, 3.32 g (38.6×0.6 mmole) of cuprous bromide was added, followed by stirring at -40° to -20° C. for 1 hour. After addition of a solution of 6.60 g (38.6 mmole) of benzyl bromide in tetrahydrofuran (15 ml), the cooling bath was removed, the reaction solution was stirred at 70° C. for 1 hour and cooled with ice, followed by addition of 1N hydrochloric acid (50 ml) and stirring. The tetrahydrofuran was distilled off under reduced pressure, and isopropyl ether was added to the residue. The insoluble matter was filtered through a bed of Hyflo Supercell, and the isopropyl ether layer was separated out, washed with water and aqueous sodium chloride solution successively, dried (magnesium sulfate) and evaporated. The residual solution was distilled under reduced pressure to give 8.62 g (83%) of 1-benzyl-2,5-dimethoxy-3,4,6-trimethylbenzene, b.p. 140°-142° C. (0.3 torr) and m.p. 70° to 71° C.

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