Reaktion #43568

Reaktionsgleichung

water

4-(4-(S)-Benzyl-2-oxo-oxazolidin-3-yl)-4-oxo-3-(R)-spiro[2.5]oct-6-ylmethyl-butyric acid tert-butyl ester

Et3N

TMS-OTf

→

4-(4-(S)-Benzyl-2-oxo-oxazolidin-3-yl)-4-oxo-3-(R)-spiro[2.5]oct-6-ylmethyl-butyric acid tert-butyl ester

4-(4-(S)-Benzyl-2-oxo-oxazolidin-3-yl)-4-oxo-3-(R)-spiro[2.5]oct-6-ylmethyl-butyric acid

Lösungsmittel

dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeet al. Synthesis 1996, 1443
2. 2
   Temperaturheated to 65° C. for 1.5 hours
3. 3
   Sonstigevolatiles were evaporated
4. 4
   workup.ADDITIONThe product was diluted with ethyl ether
5. 5
   Extraktionextracted with water, and brine
6. 6
   TrocknenThe organic layer was dried over MgSO4
7. 7
   Filtrationfiltered
8. 8
   Sonstigeevaporated

Vorschrift

4-(4-(S)-Benzyl-2-oxo-oxazolidin-3-yl)-4-oxo-3-(R)-spiro[2.5]oct-6-ylmethyl-butyric acid tert-butyl ester was prepared according to the procedures described in Example 26. A modified procedure was used for the t-Butyl ester deprotection from Trzeciak, A. et al. Synthesis 1996, 1443. 4-(4-(S)-Benzyl-2-oxo-oxazolidin-3-yl)-4-oxo-3-(R)-spiro[2.5]oct-6-ylmethyl-butyric acid tert-butyl ester (40 mg, 0.09 mmol, 1.0 eq.) was dissolved in dry dioxane (5 mL) under nitrogen followed by addition of Et3N (200 μL, 1.43 mmol, 16 eq.) and TMS-OTf (200 μL, 1.11 mmol, 12.3 eq.) via syringe. The reaction mixture stirred at room temperature overnight and then heated to 65° C. for 1.5 hours. Upon completion, 2 mL of water was added and volatiles were evaporated. The product was diluted with ethyl ether and extracted with water, and brine. The organic layer was dried over MgSO4, filtered and evaporated to provide 4-(4-(S)-Benzyl-2-oxo-oxazolidin-3-yl)-4-oxo-3-(R)-spiro[2.5]oct-6-ylmethyl-butyric acid (50 mg, quantitative) as white solid and used directly in the next step. HPLC-MS calcd. for C23H29NO5 (M+Na+) 422.2, found 422.1. 4-(4-(S)-Benzyl-2-oxo-oxazolidin-3-yl)-4-oxo-3-(R)-spiro[2.5]oct-6-ylmethyl-butyric acid was converted to the title compound according to the procedures described in example 21.

Quelle