(E)-4-(3,5-dibromo-4-hydroxyphenyl)-4-oxobut-2-enoic acid → 4-(3,5-Dibromo-4-hydroxyphenyl)-4-oxobutanoic acid

To a stirred solution of (E)-4-(3,5-dibromo-4-hydroxyphenyl)-4-oxobut-2-enoic acid (G) (2.852 g, 8.149 mmol) in ethyl acetate (27 mL) and water (3 mL) was added zinc power (5.7 g) portion wise until no further gas evolution was observed. At this point, the reaction mixture was diluted with diethyl ether (50 mL) and HCl (2 M solution, 8 mL) and the resulting mixture was filtered through a pad of Celite. After filtration, the organic solution was washed with HCl (2 M solution, 10 mL), followed by water (3×10 mL). The organic layer was then dried (MgSO4) and concentrated in vacuo to give a brown solid. This was then triturated with cold ethanol to give the title compound as a pale brown solid (1.025 g, 36%). 1H NMR δ (ppm) (DMSO-d6): 2.58 (2 H, t, J=6.12 Hz), 3.17-3.27 (2 H, m), 8.15 (2 H, s), 10.99 (1 H, s), 12.19 (1H, s)

1. filtrationthe resulting mixture was filtered through a pad of Celite
2. filtrationAfter filtration
3. washthe organic solution was washed with HCl (2 M solution, 10 mL)
4. dry with materialThe organic layer was then dried (MgSO4)
5. concentrationconcentrated in vacuo
6. customto give a brown solid
7. customThis was then triturated with cold ethanol

ORD-Eintrag

ord-4e844d73be424d60a5fbcabd6f4dd706

Quelldatensatz

uspto-grants-2012_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08283351B2