Triethylamine → Tert-butyl 4-bromo-3-methylbenzoate

Participants

Reaction Steps

4-Bromo-3-methyl-benzoic acid (2.06 g, 9.6 mmol) and thionyl chloride (2.2 ml, 30.2 mmol) in toluene (50 ml) were heated at reflux for 2 h then concentrated in vacuo and azeotroped with toluene. The residue was dissolved in THF (100 ml) and triethylamine (2.8 ml, 20.1 mmol), cooled down to 0° C. and lithium tert-butoxide (1.24 g, 15.5 mmol) was added portionwise. The mixture was stirred for 18 h at room temperature then concentrated in vacuo. The residue was dissolved in EtOAc, washed with 1M HCl, saturated NaHCO3 then brine, dried and concentrated in vacuo. The residue was purified by flash chromatography on silica gel (eluant; 5% EtOAc:95% pet. ether) to yield the title compound (1.86 g, 71%).

Provenance & Evidence