Boron trifluoride etherate → HCID 56613986, compound

Participants

Reaction Steps

90 μl of boron trifluoride etherate were added to a suspension of 564 mg (3.0 mmol) (1R,5S)-3-phenyl-4-oxa-2,6-diazabicyclo[3.2.0]hept-2-en-7-one and 1.08 g (5.4 mmol-1.8 equiv.) tert.-butyl 2-diazo-4-hydroxy-3-oxo-butanoate in 12 ml of anhydrous tetrahydrofuran at 0° C. The cooling bath was removed and after 10 minutes a clear, light yellow solution formed. After 20 minutes it was poured into a mixture of NaHCO3 solution, ice and methylene chloride. The mixture was extracted with methylene chloride (3×), washed with water and dried over magnesium sulphate. After the solvent had been evaporated off in vacuo and the residue had been crystalized from methylene chloride-ether-pentane, 861 mg (74%) of the title compound were obtained as light yellow crystals, melting point: 98° C., RF : 0.29 (toluene:ethyl acetate 2:3). Spectroscopical data identical to Example 4.

Provenance & Evidence