Reaktion #53918

Reaktionsgleichung

trans-[4-(3-Hydroxy-prop-1-ynyl)-cyclohexyl]-methyl-carbamic acid tert-butyl ester

Red-Al

KHSO4

Red-Al

→

trans-(1E)-[4-(3-Hydroxy-propenyl)-cyclohexyl]-methyl-carbamic acid tert-butyl ester

Ausbeute 79.3%

Lösungsmittel

Et2O

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturcooled (0° C.)
2. 2
   workup.WAITAfter 2 h at RT
3. 3
   Temperaturthe reaction was cooled (−50° C.)
4. 4
   SonstigeThe cooling bath was removed
5. 5
   workup.ADDITIONTHF was added
6. 6
   Filtrationthe mixture was filtered
7. 7
   SonstigeAfter evaporation
8. 8
   workup.DISSOLUTIONthe residue was dissolved in CH2Cl2
9. 9
   Trocknendried over Na2SO4
10. 10
    Sonstigeevaporated

Vorschrift

A suspension of 4.5 g (16.8 mmol) of trans-[4-(3-Hydroxy-prop-1-ynyl)-cyclohexyl]-methyl-carbamic acid tert-butyl ester in 180 ml Et2O was cooled (0° C.) and treated slowly with a solution of 13.46 ml (47.1 mmol) of Red-Al (70% in toluene). The solution was stirred 2 h at RT, cooled (0° C.) and treated again with 1.3 ml (4.7 mmol) of Red-Al (70% in toluene). After 2 h at RT, the reaction was cooled (−50° C.) and hydrolyzed with a suspension of 3 g MgSO4.7H2O, 3 g silicagel in 4 ml aqueous 10% KHSO4. The cooling bath was removed, THF was added, the mixture was filtered. After evaporation, the residue was dissolved in CH2Cl2, dried over Na2SO4 and evaporated to yield 3.59 g (quantitative) of trans-(1E)-[4-(3-Hydroxy-propenyl)-cyclohexyl]-methyl-carbamic acid tert-butyl ester, MS: 270 (MH+).

Quelle