2-Chloro-3-nitrobenzoic acid → 1-Bromo-2-chloro-3-nitrobenzene

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To an oven dried round-bottom flask fitted with stir bar and an oven dried condenser under N2 at room temperature was added 2-chloro-3-nitrobenzoic acid (6.0 g, 29.8 mmol), mercuric oxide, red (9.67 g, 44.7 mmol) and carbon tetrachloride (200 mL). The reaction mixture heated to 90° C. for 30 minutes with irradiation from a 150 W TYPE A utility light bulb. The reaction mixture was then cooled to approximately 60° C. and bromine (2.30 mL, 44.7 mmol) added dropwise via syringe and the nitrogen inlet was replaced with an Ar balloon. The reaction mixture was heated again to 90° C. for 4 hours under constant irradiation from the light bulb. The reaction was allowed to cool to room temperature, quenched with saturated aqueous NaHCO3 solution and DCM and stirred for 30 minutes. The phases partitioned upon standing and then were separated. The aqueous portion was extracted with DCM. The combined organic phases were washed with water, brine, dried (Na2SO4), filtered and concentrated in vacuo to afford 7.04 g of 1-bromo-2-chloro-3-nitrobenzene: 1H NMR (400 MHz, CDCl3) δ 7.31 (t, J=8.0 Hz, 1H) 7.74 (dd, J=8.2, 1.2 Hz, 1H) 7.87 (dd, J=8.0, 1.4 Hz, 1H).

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