1,8-Diazabicyclo(5.4.0)undec-7-ene → 2-Benzyloxycarbonylamino-3-bicyclo[2.2.1]hept-2-yl-acrylic acid methyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

In a round bottom flask was placed N-(benzyloxycarbonyl)-α-phosphonoglycine methyl ester (2.05 g, 6.18 mmol) in dichloromethane (5 mL) and cooled to 0° C. in an ice bath. To this mixture was then added slowly 1,8-diazabicyclo[5.4.0]undec-7-ene (801 μL, 5.36 mmol) and it was stirred at 0° C. for 20 min. The mixture was then treated with a solution of bicyclo[2.2.1]heptane-2-carbaldehyde (512 mg, 4.12 mmol) in dichloromethane (5 mL). After the addition was complete, the mixture was allowed to warm to 25° C. and stirred overnight. The mixture was concentrated in vacuo and then dissolved in ethyl acetate (50 mL) and washed with a saturated aqueous ammonium chloride solution (2×25 mL). The organic layer was dried over sodium sulfate, filtered and concentrated in vacuo. Purification by AnaLogix IntelliFlash chromatography (25 g column, 15% ethyl acetate/hexanes to 34% ethyl acetate/hexanes) afforded 2-benzyloxycarbonylamino-3-bicyclo[2.2.1]hept-2-yl-acrylic acid methyl ester (491 mg, 36%) as a clear colorless oil.

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