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

Participants

Reaction Steps

Into a Solution of 2-bromo-1,3-dimethoxy-5-(methoxymethyl)benzene (121.3 g) in tetrahydrofuran (730 mL), n-butyllithium (2.64M hexane solution; 182 mL) was dropped at −78° C., and the mixture was stirred for 20 minutes. To the reaction mixture was added a solution of trimethoxyborane (61.7 mL) intetrahydrofuran (20 mL) at −78° C. The temperature was raised until the inner temperature of the reaction mixture reached −10° C., a saturated ammonium chloride aqueous solution (730 mL) was added, and the mixture was further stirred for 15 minutes. To the resulting reaction mixture was added ethyl acetate, extraction with ethyl acetate was performed, and the resulting organic layer was washed with saturated saline, and dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure. The resulting residue was purified by silica gel column chromatography, and from a fraction of n-hexane:ethyl acetate (2:3), 90.4 g of a title compound was obtained as white solid.

Provenance & Evidence