Reaktion #460511

Reaktionsgleichung

diphenylmethyl 2-[(3R,4R)-4-(p-toluenesulfonylthio)-3-phenoxyacetamido-2-oxo-azetidin-1-yl]-3-trifluoromethanesulfonyloxy-2-butenoate

triethylamine

→

diphenylmethyl 2-[(3R,4R)-4-(p-toluenesulfonylthio)-3-phenoxyacetamido-2-oxo-azetidin-1-yl]-2,3-butadienoate

Ausbeute 103.9%

Lösungsmittel

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   WaschenReverse-phase chromatography (C-18 column, eluting with 65% acetonitrile - 35% of 0.01M phosphate pH 6.5 buffer)
2. 2
   Sonstigeconsumption of the starting material after 45 min with formation of a single,
3. 3
   Waschenfaster-eluting product
4. 4
   workup.ADDITION0.05M sulfuric acid and ethyl acetate was added to the reaction mixture
5. 5
   Sonstigeby separating the two phases
6. 6
   TrocknenThe organic phase was dried with sodium sulfate
7. 7
   Sonstigeevaporated

Vorschrift

Embodiment a: A solution of diphenylmethyl 2-[(3R,4R)-4-(p-toluenesulfonylthio)-3-phenoxyacetamido-2-oxo-azetidin-1-yl]-3-trifluoromethanesulfonyloxy-2-butenoate (XVa, 0.300 g, 0.00036 mole) in dry tetrahydrofuran (3 mL) was treated with triethylamine (0.077 mL, 0.00036 mole) for 1 h at room temperature. Reverse-phase chromatography (C-18 column, eluting with 65% acetonitrile - 35% of 0.01M phosphate pH 6.5 buffer) showed complete consumption of the starting material after 45 min with formation of a single, faster-eluting product. 0.05M sulfuric acid and ethyl acetate was added to the reaction mixture, followed by separating the two phases. The organic phase was dried with sodium sulfate and evaporated to give 0.245g of diphenylmethyl 2-[(3R,4R)-4-(p-toluenesulfonylthio)-3-phenoxyacetamido-2-oxo-azetidin-1-yl]-2,3-butadienoate (Ia) as a colorless foam (quantitative yield).

Quelle