Dimethylformamide → HCID 19737922, compound

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of the 1,3-dibromobenzofuran 11 (10 g, 30.9 mmol) in anhydrous THF (250 mL) at -78° C. under nitrogen was added a 2.5M butyllithium in hexane solution (13.6 mL, 33.9 mmol). The resulting red solution was warmed to -50° C. and held there for 10 min. before anhydrous DMF (2.6 mL, 33.9 mmol) was added dropwise. The resulting rust colored solution was stirred an additional 20 min. at -50° to -40° C. before being quenched with saturated ammonium chloride solution (25 mL). The THF was removed under vacuum and the residue was dissolved in ethyl acetate (EtOAc) and washed sequentially with water, saturated aqueous ammonium chloride solution, water and brine. The organic solution was then dried with magnesium sulfate and decolorized with Norite. The mixture was then filtered and concentrated under vacuum. The residue was triturated with ether/hexane to provide 4.0 g of pale yellow flakes of dibenzofuran 35. The mother liquor was then chromatographed (silica gel, 30% EtOAc in hexanes) to provide an additional 2.1 g of dibenzofuran 35 (total yield: 73%).

Provenance & Evidence