Hydrochloric Acid → 4-Ethoxy-2,3,3'-trifluorobiphenyl

関与物質

反応手順

Mixture of 20.0 g (79.3 mmol) of 4-ethoxy-2,3-difluoroiodobenzene [obtained by lithiating 4-ethoxy-2,3-difluorobenzene with sec-butyl lithium and then reacting with iodine], 18.9 g (118.9 mmol) of dihydroxy(3-fluorophenyl)borane [obtained by reacting a Grignard reagent, which was prepared from 3-fluorobromobenzene and magnesium, with trimethoxyborane and then hydrolyzing with hydrochloric acid], 21.9 g (158.6 mmol) of K2CO3, 2.0 g of 5% Pd—C, and 100 ml of mixed solvent of toluene/ethanol/ water (1/1/1) was heated to reflux for 13 hours. Subsequently, after the catalyst was filtered off, the mixture was subjected to extraction with toluene, and the organic layer thus obtained was washed with water thrice and then dried over anhydrous magnesium sulfate. The solvent was distilled off under a reduced pressure and the residue thus obtained was subjected to silica gel column chromatography (eluent: heptane/toluene=8/2) to obtain 17.3 g of a crude 4-ethoxy-2,3,3′-trifluorobiphenyl. (Yield: 86.2%)

情報源と証拠