6-{2-[2,4-dichloro-6-(2-methoxyethoxymethoxy) phenyl]ethyl}-3,4,5,6-tetrahydro-4-hydroxy-2H-pyran-2-one → 6-{2-(2,4-Dichloro-6-hydroxyphenyl)-ethyl}-3,4,5,6-tetrahydro-4-hydroxy-2H-pyran-2-one

Zinc bromide (2.4 g, 10 mmole) was added to a solution of 6-{2-[2,4-dichloro-6-(2-methoxyethoxymethoxy) phenyl]ethyl}-3,4,5,6-tetrahydro-4-hydroxy-2H-pyran-2-one (780 mg, 2 mmole) in methylene chloride (12 ml). The resulting mixture was stirred at 20° C. for 2 hours, then quenched with saturated sodium bicarbonate solution (50 ml) and diluted with ether (200 ml). The ethereal layer was washed with brine, dried over MgSO4, filtered and evaporated. The residue was chromatographed on a 50 mm low-pressure column with 6 inches of silica gel (230-400 mesh). The column was eluted with 470 ml of methylene chloride-acetone (4:1, v:v). The next 330 ml provided the title compound as a golden glass (100 mg., 16%): pmr (CDCl3)δ2.62 (2H, d), 4.29 (H, m), 4.78 (H, m), 6.87 (2H, s).

1. customquenched with saturated sodium bicarbonate solution (50 ml)
2. additiondiluted with ether (200 ml)
3. washThe ethereal layer was washed with brine
4. dry with materialdried over MgSO4
5. filtrationfiltered
6. customevaporated
7. customThe residue was chromatographed on a 50 mm low-pressure column with 6 inches of silica gel (230-400 mesh)
8. washThe column was eluted with 470 ml of methylene chloride-acetone (4:1, v:v)

ORD-Eintrag

ord-8194bd8a3b384bcbb930c36bb46a90e5

Quelldatensatz

uspto-grants-1987_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US04710513