Imidazole → (3S)-3-(tert-Butyldimethylsiloxy)-3-cyclohexylprop-1-yne

Reaktionsgleichung

N1[CH:5]=[CH:4]N=C1.[C:6]([Si:10]([CH3:13])([CH3:12])Cl)([CH3:9])([CH3:8])[CH3:7].O.[CH3:15][CH2:16][CH2:17][CH2:18][CH2:19][CH3:20].CN(C)[CH:23]=[O:24]>>[Si:10]([O:24][C@@H:23]([CH:17]1[CH2:16][CH2:15][CH2:20][CH2:19][CH2:18]1)[C:4]#[CH:5])([C:6]([CH3:9])([CH3:8])[CH3:7])([CH3:13])[CH3:12]

Komponenten

Edukt 5

HCID 795Imidazole

HCID 962Water

HCID 6228Dimethylformamide

HCID 8058Hexane

HCID 28928tert-Butyldimethylsilyl chloride

Produkt 1

HCID 11983898(3S)-3-(tert-Butyldimethylsiloxy)-3-cyclohexylprop-1-yne

Versuchsvorschrift

To a solution of (S)-3-cyclohexylprop-1-yn-3-ol, (obtained according to Preparation 10) (2.76 g, 0.02 mol), in 10 ml N,N-dimethylformamide (DMF), cooled to 0° C., was added imidazole (2.1 g), followed by tert-butyldimethylchlorosilane (3.1 g, 0.02 mol). The mixture was stirred for 3 h. Water (80 ml) and hexane (80 ml) were added; the organic layer was separated and combined with 2×80 ml of hexane extractions of the aqueous layer. The solvent was removed (in vacuo), after drying over sodium sulfate, to give a crude residue (4.3 g) which was chromatographed on silica gel (80 g), eluting with ethyl acetate-hexane (2:1, v/v) to afford (S)-3-tert-butyldimethylsilyloxy-3-cyclohexylprop-1-yne.