Methyl Isobutyl Ketone → Sodium (Z)-(2S,3S,5R)-3-(2-cyanoethenyl)-3-methyl-4,4,7-trioxo-4-thia-1-aza-bicyclo[3.2.0]heptane-2-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

95 mg (0.2 mmol) of benzhydryl (Z)-(2S,3S,5R)-3-(2-cyanoethenyl)- 3-methyl-4,4,7-trioxo-4-thia-1-aza-bicyclo[3.2.0]heptane-2-carboxylate were dissolved in 3 ml of m-cresol and stirred at 50° C. for 45 minutes. The reaction mixture was treated with 10 ml of isobutyl methyl ketone and 120 μl of sodium 2-ethylcaproate (2N in ethyl acetate, 1.1 eq.). The mixture was extracted twice with 3 ml of water each time, the combined aqueous phases are washed with 10 ml of isobutyl methyl ketone and lyophilized. The yellow lyophilizate was dissolved in 1.3 ml of water and chromatographed over polymeric hydrophobic gel. Yield: 50 mg (80%) of colorless lyophilizate IR (KBr): 2222, 1782, 1626, 1395, 1323, 1141 cm-1 1 H-NMR (250MHz, D2O): δ[ppm]=1.94(s,3H), 3.47(dd,1H,J=16Hz, 1.6Hz, 6-H), 3.73(dd, 1H, J=16Hz, 4.4Hz, 6-H), 4.80(s,1H,2-H), 5.19(dd, 1H, J=16Hz, 4.4Hz,5-H), 6.15(d.1H,J=12Hz,=CH), 6.68 (d,1 H,J=12Hz,=CH).

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