Nitrogen → HCID 21694197, compound

Participants

Reaction Steps

A solution of 3-bromo-2-hydroxybenzaldehyde (20 g, 0.1 mol) in 150 mL of CH2Cl2 was added HBF4.Et2O (1.5 mL, 0.01 mmol). A solution of ethyl diazoacetate (27.36 g, 0.24 mol) in CH2Cl2 (50 mL) was introduced into the reaction mixture, during about 3-6 min and the evolution of N2 gas observed, and the reaction was not allowed to go above 38° C. Once gas evolution ceased, the reaction mixture was concentrated by rotary evaporator and H2SO4 (20 mL) was added to the mixture while stirring. After 30 min, the mixture was diluted with CH2Cl2 (200 mL) and the H2SO4 was quenched with solid NaHCO3. The mixture was then filtered through silica gel (100 g), and concentrated by rotary evaporator to give an oil, then exacted with EtOAc (500 mL), and washed with brine (100 mL), dried over Na2SO4. The solvent was concentrated in vacuo. The residue was separated and purified with silica gel chromatography to give product ethyl 7-bromo-1-benzofuran-3-carboxylate.

Provenance & Evidence