Boron tribromide → 1,3-Benzenediol, 5-chloro-

A solution of 5-chloro-1,3-dimethoxybenzene (5.41 g, 31.3 mM) in methylene chloride (75 mL) at −78° C. was stirred with a 1M solution of BBr3 in methylene chloride (63 mL) for 45 minutes. The reaction was allowed to warm to room temperature overnight and diluted with water (75 mL). The layers were separated and the aqueous layer washed two times with methylene chloride. The aqueous layer was acidified with 1N HCl and extracted 3 times with ethyl acetate. The combined organic layers were washed with 1N sodium thiosulfate (1×35 mL) and water (1×25 mL). The organic layer was dried (MgSO4), filtered and concentrated under reduced pressure and purified by chromatography (methylene chloride/acetone) to provide the titled compound. MS ESI(−)) m/e 143 (M−H)+; 1H NMR (300 MHz, CDCl3) δ 6.45 (d, 2H), 6.25 (t, 1H), 5.41 (bs, 2H).

1. customThe layers were separated
2. washthe aqueous layer washed two times with methylene chloride
3. extractionextracted 3 times with ethyl acetate
4. washThe combined organic layers were washed with 1N sodium thiosulfate (1×35 mL) and water (1×25 mL)
5. dry with materialThe organic layer was dried (MgSO4)
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure
8. custompurified by chromatography (methylene chloride/acetone)

ORD-Eintrag

ord-d02b4d6792e54ef49b8f8bdf66bdb5ba

Quelldatensatz

uspto-grants-2005_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06972340B2