Reaktionsgleichung
[CH3:1][C:2]([Si:5]([CH3:23])([CH3:22])[O:6][CH2:7][CH:8]1[CH:11]([CH2:12][O:13][Si:14]([C:17]([CH3:20])([CH3:19])[CH3:18])([CH3:16])[CH3:15])[CH2:10][C:9]1=[O:21])([CH3:4])[CH3:3].C([BH-](C(CC)C)C(CC)C)(CC)C.[K+].C(O)(=O)C>O1CCCC1>[CH3:4][C:2]([Si:5]([CH3:23])([CH3:22])[O:6][CH2:7][CH:8]1[CH:11]([CH2:12][O:13][Si:14]([C:17]([CH3:20])([CH3:19])[CH3:18])([CH3:16])[CH3:15])[CH2:10][CH:9]1[OH:21])([CH3:1])[CH3:3]Komponenten
Edukt 3
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Reaktionsbedingungen
- Temperatur
- -78 °C
Versuchsvorschrift
2,3-Bis(((1,1-dimethylethyl)dimethylsilyl)oxymethyl)cyclobutanone (10.2 g, 28.4 mmol) from Step B was dissolved in tetrahydrofuran (THF) and the solution was cooled to -78° C. under a nitrogen atmosphere. To the THF solution at -78° C. was slowly added, with stirring, 31 mL (31 mmol) of potassium tri-sec-butylborohydride (sold by Aldrich Chemical Company as a 1M solution in THF under the registered trademark K-Selectride®). After stirring for 0.5 h at -78° C., the reaction mixture was allowed to warm to 0° C. and it was stirred for 40 minutes at 0° C. One equivalent (1.9 mL) of glacial acetic acid was added and the reaction mixture was concentrated in vacuo to approximately 50 mL. The concentrate was diluted with 1 L of methylene chloride and the resultant solution was washed with 400 mL of 5% aqueous sodium bicarbonate solution, dried over anhydrous magnesium sulfate, filtered and concentrated to a syrup. The syrup (15.5 g) was chromatographed on a 4.5×45 cm silica gel column eluted @ 2-5 psi with 2 L of methylene chloride. All fraction containing the desired product were combined and concentrated. The residue (10 g) was rechromatographed as described above to give 6.3 g (62% yield) of the title compound as a syrup; 1H NMR (CDCl3) δ 0.07 (d, 12H), 0.92 (d, 18H), 2.01 (m, 1H), 2.13 (m, 2H), 2.25 (m, 1H), 2.40 (m, 1H), 3.35 (d, 1H), 3.55 (m, 2H), 3.86 (dd, 1H), 3.98 (dd, 1H); MS DCI-NH3M/Z: 361 (M+H)+.
Aufarbeitung
- stirringAfter stirring for 0.5 h at -78° C.
- temperatureto warm to 0° C.
- stirringit was stirred for 40 minutes at 0° C
- concentrationthe reaction mixture was concentrated in vacuo to approximately 50 mL
- additionThe concentrate was diluted with 1 L of methylene chloride
- washthe resultant solution was washed with 400 mL of 5% aqueous sodium bicarbonate solution
- dry with materialdried over anhydrous magnesium sulfate
- filtrationfiltered
- concentrationconcentrated to a syrup
- customThe syrup (15.5 g) was chromatographed on a 4.5×45 cm silica gel column
- washeluted @ 2-5 psi with 2 L of methylene chloride
- additionAll fraction containing the desired product
- concentrationconcentrated
- customThe residue (10 g) was rechromatographed
Quellen und Nachweise
- ORD-Eintrag
- ord-a85057aaa6914c52a223e4b75364a097
- Quelldatensatz
- uspto-grants-1993_09
- Patentnummer
- US05246931
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