Trimethyl borate → 2,6-Dimethoxy-4-methoxymethylphenylboric acid

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

n-Butyllithium (2.64M hexane solution; 182 mL) was added dropwise to a solution of 2-bromo-1,3-dimethoxy-5-(methoxymethyl)benzene (121.3 g) in tetrahydrofuran (730 mL) at −78° C., and the mixture was stirred for 20 minutes. A solution of trimethoxyborane (61.7 mL) in tetrahydrofuran (20 mL) was then added to the reaction mixture at −78° C. When internal temperature was raised to −10° C., to the reaction mixture was added saturated aqueous ammonium chloride (730 mL), and stirring was continued for 15 minutes. The obtained reaction mixture was extracted with ethyl acetate, the extract was washed with brine and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography and the title compound (90.4 g) was obtained as a white solid from the n-hexane:ethyl acetate (2:3) fraction.

Herkunft & Nachweise