Boron tribromide → 4,4'-Dihydroxybenzil

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

1,2-bis(4-methoxyphenyl)ethane-1,2-dione (5 g, 18.52 mmol) was dissolved in CH2Cl2 and cooled to −78° C. (solid occurred again). BBr3 (8.3 m, 87.82 mmol) was added and mixture was allowed to warm to room temperature and stirred for 15 hrs. TLC check showed 1,2-bis(4-methoxyphenyl)ethane-1,2-dione completely disappeared. The reaction mixture was poured into ice, extracted by EtOAc, washed with NaCl solution, dried over MgSO4. The solvent was removed by vacuum, and the residue was purified by column chromatography to give compound 5, 1,2-bis(4-hydroxyphenyl)ethane-1,2-dione, as confirmed by the following nuclear magnetic resonance (NMR) data obtained therefrom: 1H NMR (500 MHz, DMSO): δ 10.8 (s, 2H), 7.71 (d, J=8.8 MHz, 4H), 6.90 (d, J=8.8 MHz, 4H) ppm.

Herkunft & Nachweise