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ChemicalBook CAS DataBase List 5-BROMOPROTOCATECHUALDEHYDE
16414-34-9

5-BROMOPROTOCATECHUALDEHYDE synthesis

6synthesis methods
-

Yield: 100%

Reaction Conditions:

Stage #1:5-bromo-4-hydroxy-3-methoxybenzaldehyde with boron tribromide in dichloromethane at 0 - 20; for 2.83333 h;
Stage #2: with methanol in dichloromethane at 0;

Steps:

31.b
(b) 3-Bromo-4,5-dihydroxybenzaldehydeTo a solution of 3-bromo-4-hydroxy-5-rnethoxybenzaldehyde (12. Ig, 0.52 mol) in dichloromethane (200 ml) was added 1.0 M boron tribromide in dichloromethane (2.2 eq, 115 ml) at 0°. The reaction was stirred at 0° for 20 min, then at ambient temperature for 2.5h. The reaction was then cooled to 0°, and quenched by the slow addition of methanol. The solvents were removed under reduced pressure and the trimethyl borate was removed by azeotropation with added methanol. Drying in vacuo yielded the desired product (11.5 Ig, 100%). MS (ES) m/z 217 (M+H)+

References:

GLAXO GROUP LIMITED WO2007/122258, 2007, A1 Location in patent:Page/Page column 44-45

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