2,2-Dimethoxypropane → 2-[(4R, 6S)-2,2-dimethyl-6-benzoyloxymethyl-1,3-dioxan-4-yl]acetic tert-butyl ester

HRID 10132

Reaktionsgleichung

Reaktionsgleichung von HRID 10132
[C:1]([O:5][C:6](=[O:23])[CH2:7][CH:8]([OH:22])[CH2:9][C@H:10]([OH:21])[CH2:11][O:12][C:13](=[O:20])[C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1)([CH3:4])([CH3:3])[CH3:2].CO[C:26](OC)([CH3:28])[CH3:27].C(=O)([O-])O.[Na+]>C(Cl)Cl>[C:1]([O:5][C:6](=[O:23])[CH2:7][C@H:8]1[CH2:9][C@@H:10]([CH2:11][O:12][C:13](=[O:20])[C:14]2[CH:15]=[CH:16][CH:17]=[CH:18][CH:19]=2)[O:21][C:26]([CH3:28])([CH3:27])[O:22]1)([CH3:4])([CH3:2])[CH3:3]

Komponenten

5

Edukt 3

HCID 64952,2-DimethoxypropaneHCID 516892Sodium BicarbonateHCID 21040752(5S)-6-benzoyloxy-3,5-dihydroxyhexanoic tert-butyl ester

Produkt 1

HCID 101333842-[(4R, 6S)-2,2-dimethyl-6-benzoyloxymethyl-1,3-dioxan-4-yl]acetic tert-butyl esterAusbeute 72 %

Reagenzien, Katalysatoren, Lösungsmittel 1

HCID 6344DichloromethaneLösungsmittel

Reaktionsbedingungen

Temperatur
20 °C

Versuchsvorschrift

To a solution composed of 8.94 g (27.6 mmol) of (5S)-6-benzoyloxy-3,5-dihydroxyhexanoic tert-butyl ester produced in Example 15, 35.8 mL of 2,2-dimethoxypropane, and 2.5 mL of methylene chloride was added 269 mg (1.4 mmol) of p-toluenesulfonic acid-1H2O, and the mixture was stirred at 20° C. for 4 hours, after which 500 mL of saturated sodium hydrogen carbonate solution was added. The aqueous layer was separated and further extracted with 2 portions of methylene chloride, 20 mL each, and the organic layers were combined. The combined solution was dehydrated over anhydrous sodium sulfate and the solvent was distilled off under reduced pressure to give a colorless oil. This residue was purified by silica gel column chromatography (Kieselgel 60, product of Merck; hexane:acetone=10:1) to give 7.24 g of 2-[(4R,6S)-2,2-dimethyl-6-benzoyloxymethyl-1,3-dioxan-4-yl]acetic tert-butyl ester (white solid). Yield: 72%.

Aufarbeitung

  1. customThe aqueous layer was separated
  2. extractionfurther extracted with 2 portions of methylene chloride, 20 mL each
  3. distillationthe solvent was distilled off under reduced pressure
  4. customto give a colorless oil
  5. customThis residue was purified by silica gel column chromatography (Kieselgel 60, product of Merck; hexane:acetone=10:1)

Quellen und Nachweise

ORD-Eintrag
ord-980177fca8a041c8ab1d3755eefdece6
Quelldatensatz
uspto-grants-2006_08
Patentnummer
US07094594B2

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