Triethylamine → HCID 131713497, compound

Participants

Reaction Steps

Sodium (5R,6R)-3-[(E)-2-acetamidoethenylthio]-6-[(S)-1-hydroxyethyl]-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate (200 mg; 85% pure) in water (10 ml) was treated with dichloromethane (10 ml) containing Aliquat 336 (600 mg). After shaking and separating the aqueous layer was again treated with dichloromethane (10 ml) containing Aliquat 336 (600 mg). The two dichloromethane extracts were dried (MgSO4) and evaporated to leave a mixture of Aliquat 336 and the quaternary ammonium salt corresponding to the starting sodium salt. This mixture was taken up in dry dichloromethane (10 ml), cooled to -70° and treated with triethylamine in dichloromethane (0.55 ml; 100 mg/ml), followed by bromine in carbon tetrachloride (0.82 ml; 100 mg/ml). After stirring in the cold for 25 minutes the mixture was warmed to room temperature, washed with water (3.5 ml) and extracted with saturated aqueous NaCl (2×5 ml). The NaCl extracts were combined and loaded onto a column of DIAION HP20 (18×1 cm). The column was eluted with saturated aqueous NaCl (25 ml) and then with deionised water. Some fractions containing the title compound (λmax ca 299 and 248 nm) were obtained. The column was then eluted with water containing 10% ethanol to give further fractions containing the title compound. Fractions containing the title compound were combined and evaporated in vacuo to low volume, ethanol was added and evaporated to low volume (4×), and toluene added and evaporated to dryness (3×) to give the title compound (29 mg) of estimated purity of ca 40%:λmax (H2O) 300(6,100), 246 (9,000) nm; λmax(KBr) 1750, 1690, 1620 cm-1.

Provenance & Evidence