Reaktion #332630

Reaktionsgleichung

Ethyl 2-(5-((tert-butyldiphenylsilyloxy)methyl)-4-((2R,6S)-2,6-dimethylmorpholino)-2,3-difluorophenyl)-2-oxoacetate

Intermediate 114

Ethyl 2-(5-((tert-butyldiphenylsilyloxy)methyl)-4-((2R,6S)-2,6-dimethylmorpholino)-2,3-difluorophenyl)-2-oxoacetate

hydroxylamine hydrochloride

→

title compound

Ethyl 2-(5-((tert-butyldiphenylsilyloxy)methyl)-4-((2R,6S)-2,6-dimethylmorpholino)-2,3-difluorophenyl)-2-(hydroxyimino)acetate

Lösungsmittel

pyridine

Reaktionsbedingungen

Aufarbeitung

1. 1
   EinengenThe reaction was concentrated
2. 2
   Sonstigeto remove excess pyridine
3. 3
   workup.DISSOLUTIONThe residue was dissolved in ethyl acetate
4. 4
   Waschenwashed with water and brine 3×
5. 5
   TrocknenThe organic layer was dried over MgSO4
6. 6
   Einengenconcentrated
7. 7
   SonstigeThe residue was purified by silica gel column chromatography

Vorschrift

Ethyl 2-(5-((tert-butyldiphenylsilyloxy)methyl)-4-((2R,6S)-2,6-dimethylmorpholino)-2,3-difluorophenyl)-2-oxoacetate (Intermediate 114, 2.808 g, 4.71 mmol) and hydroxylamine hydrochloride (0.360 g, 5.18 mmol) were dissolved in pyridine (40 ml) and stirred at 115° C. for 16 hours. The reaction was concentrated to remove excess pyridine. The residue was dissolved in ethyl acetate and washed with water and brine 3×. The organic layer was dried over MgSO4 and concentrated. The residue was purified by silica gel column chromatography using a gradient of hexanes to ethyl acetate to give the title compound as a mixture of oxime isomers (1.924 g, 3.15 mmol, 66.8%).

Quelle