Sodium hydride → 4-[5-(3-Ethoxycarbonyl-2-oxo-propoxymethyl)-2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy]-3-oxo-butyric acid ethyl ester

HRID 1248

Reaktionsgleichung

Reaktionsgleichung von HRID 1248
[H-].[Na+].[CH3:3][C:4]1([CH3:13])[O:8][CH:7]([CH2:9][OH:10])[CH:6]([CH2:11][OH:12])[O:5]1.Cl[CH2:15][C:16](=[O:23])[CH2:17][C:18]([O:20][CH2:21][CH3:22])=[O:19]>O1CCCC1.S([O-])(O)(=O)=O.C([N+](CCCC)(CCCC)CCCC)CCC>[CH2:21]([O:20][C:18](=[O:19])[CH2:17][C:16](=[O:23])[CH2:15][O:10][CH2:9][CH:7]1[CH:6]([CH2:11][O:12][CH2:15][C:16](=[O:23])[CH2:17][C:18]([O:20][CH2:21][CH3:22])=[O:19])[O:5][C:4]([CH3:13])([CH3:3])[O:8]1)[CH3:22]

Komponenten

6

Edukt 3

HCID 24758Sodium hydrideHCID 69484Ethyl 4-chloroacetoacetateHCID 318275[5-(Hydroxymethyl)-2,2-dimethyl-1,3-dioxolan-4-yl]methanol

Produkt 1

HCID 867521794-[5-(3-Ethoxycarbonyl-2-oxo-propoxymethyl)-2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy]-3-oxo-butyric acid ethyl esterAusbeute 43,7 %

Reagenzien, Katalysatoren, Lösungsmittel 2

HCID 94433Tetrabutylammonium hydrogen sulfateKatalysatorHCID 8028TetrahydrofuranLösungsmittel3×

Versuchsvorschrift

To a suspension of sodium hydride (4.0 g, 60% dispersion in oil) in tetrahydrofuran (150 mL) under a nitrogen atmosphere was added a solution of 2,2-dimethyl-[1,3]dioxolane-4,5-dimethanol (VII, 4.05 g) in tetrahydrofuran (25 mL) over 2 min at room temperature, followed by solid tetrabutylammonium hydrogen sulfate (0.4 g). The resulting mixture was cooled in an ice bath and a solution of ethyl 4-chloroacetoacetate (VIII, 8.1 g) in tetrahydrofuran (25 mL) was added dropwise over a period of 15 min. The reaction mixture was warmed to room temperature over 1 h then refluxed for 6 h. On cooling to room temperature, the reaction mixture was quenched with 1N hydrochloric acid (20 mL) and volatile materials were removed under reduced pressure. The aqueous phase was extracted with ethyl acetate (3×30 mL). The combined organic fractions was washed with brine, dried (sodium sulfate), filtered and concentrated in vacuo. The residue was purified by flash chromatography on silica gel (grade 9385, Merck, 230-400 mesh, 60 Å) using a mixture of hexane and ethyl acetate (8:2, 7:3 and 6:4; 500 mL each) as eluent, thereby affording the title compound (IX 4.5 g) as an oil and the mono O-alkylated compound, 4-(2-chlorophenyl)-2-(5-hydroxymethyl-2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy-methyl-1,4-dihydro-6-methyl-3,5-pyridinedicarboxylic acid 3-ethyl 5-methyl ester (X, 1.95 g). Compound IX. IR (neat, cm-1): 1723, 1636; MS (CI): 436 (100%, [M+NH4 ]+). Compound X. IR (neat, cm-1): 3455, 1734;

Aufarbeitung

  1. temperatureThe resulting mixture was cooled in an ice bath
  2. temperaturethen refluxed for 6 h
  3. temperatureOn cooling to room temperature
  4. customthe reaction mixture was quenched with 1N hydrochloric acid (20 mL) and volatile materials
  5. customwere removed under reduced pressure
  6. extractionThe aqueous phase was extracted with ethyl acetate (3×30 mL)
  7. washThe combined organic fractions was washed with brine
  8. dry with materialdried (sodium sulfate)
  9. filtrationfiltered
  10. concentrationconcentrated in vacuo
  11. customThe residue was purified by flash chromatography on silica gel (grade 9385, Merck, 230-400 mesh, 60 Å)
  12. additiona mixture of hexane and ethyl acetate (8:2, 7:3 and 6:4; 500 mL each) as eluent

Quellen und Nachweise

ORD-Eintrag
ord-70ae7882edfe4b59882bded66d4f531c
Quelldatensatz
uspto-grants-1998_03
Patentnummer
US05723618

Verknüpfte Notizen

Wird geladen…