1,3-Dibromopropane → 7-Bromo-8-fluoro-3,4-dihydro-2H-benzo-[1,4]-dioxepine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To 1.50 g (7.25 mmol) of 4-bromo-5-fluorobenzene-1,2-diol in 25 ml DMF are added 5.90 g (18.1 mmol) Cs2CO3 and 0.89 ml (8.70 mmol) 1,3-dibromopropane. The reaction mixture is stirred at 120° C. over night. The solvent is removed in vacuo and to the residue is added water. After extracting with EtOAc the org. phases are combined, washed with sat. aq. NaCl solution and dried over MgSO4. The solvent is removed in vacuo and the resulting residue is purified by column chromatography (silica gel, PE/EtOAc 9/1→7/3).

Herkunft & Nachweise