Reaktion #1447130
ord-f4ff62e636f846fa89a20d0515c7123c
Reaktionsgleichung
Edukte
Reagenzien
Lösungsmittel
Reaktionsbedingungen
Aufarbeitung
- 1workup.ADDITIONwas treated under dry nitrogen
- 2Einengenconcentrated in vacuo
- 3Sonstigethe residue partitioned between 5% aqueous ammonium chloride solution and ethyl acetate (2×60 mL)
- 4WaschenThe organic layers were washed with brine
- 5Trocknendried over magnesium sulfate
- 6Filtrationfiltered
- 7Sonstigeevaporated to dryness
- 8Sonstigechromatographed on silica gel (60 g)
- 9WaschenElution with 2% methanol in chloroform
Vorschrift
A suspension of 2.6-diaza-bicyclo[5.2.0]non-1(7)-ene-8,9-dione (2) (4 mmol, 608 mg) in N,N-dimethylformamide (60 mL) was treated under dry nitrogen and under stirring with 60% sodium hydride in oil (4.1 mmol, 164 mg). After 30 minutes at ambient temperature the yellow reaction mixture was cooled to 0° C. and a solution of diethyl 3,3′-[(vinylphosphoryl)bis(oxy)]dibenzoate (3) (4 mmol, 1.618 g) in N,N-dimethylformamide (30 mL) was added at once under vigorous stirring. The reaction mixture was then stirred at ambient temperature overnight, concentrated in vacuo and the residue partitioned between 5% aqueous ammonium chloride solution and ethyl acetate (2×60 mL). The organic layers were washed with brine, dried over magnesium sulfate, filtered and evaporated to dryness. The residue (>1.5 g) was flash chromatographed on silica gel (60 g). Elution with 2% methanol in chloroform afforded 600 mg (27%) of the desired title compound as a white powder; mp 116-7° C. MS (ES+): m/e 557.2 [M+H]+.