2-Bromobenzoic acid → HCID 12249440, compound

Participants

Reaction Steps

To a cold (ice/water bath) stirred mixture of 2-bromobenzoic acid (20.1 g, 0.1 mol) and ethyl acetoacetate (13.01 g, 0.1 mol) in 1,4-dioxane (200 ml) sodium hydride (8 g, 0.2 mol, 60% dispersion in mineral oil) was added in small portions. After addition the cold bath was removed and the reaction mixture was allowed to stir at ambient temperature for 10 min. Copper (I) bromide (15.2 g, 0.106 mol) was added in portions and the obtained mixture was heated at reflux for 1 h. It was allowed to cool and stirred overnight at ambient temperature. The obtained green suspension was quenched with ethyl acetate (200 ml) and ice (300 g) and acidified with concentrated HCl (50 ml). The organic phase was washed with aq. 2 M HCl (2×100 ml) and brine, dried (Na2SO4) and evaporated in vacuo. The remaining mineral oil was removed by decantation after shaking with heptane (3×100 ml) and evaporation. Yield ca. 20 g, pale-yellow oil. The crude product was used in the next step without further purification. LC-MS (m/z) 205 ([M−CO2]+); tR=0.91. 1H NMR (500 MHz, DMSO-d6): mixture of at least 3 tautomers.

Provenance & Evidence