1,8-Diazabicyclo(5.4.0)undec-7-ene → ethyl 2-[4-[((3S)-1-tert-butoxycarbonyl-3-pyrrolidinyl)oxy]phenyl]-3-(7-cyano-2-naphthyl)acrylate

Participants

Reaction Steps

8.40 g of (7-cyano-2-naphthyl)methyltriphenylphosphonium bromide and 5.0 g of ethyl 2-[4-[((3S)-1-tert-butoxycarbonyl-3-pyrrolidinyl)oxy]phenyl]-2-oxoacetate were suspended in a mixture of 100 ml of tetrahydrofuran and 100 ml of ethanol. With stirring, to the resulting suspension was added 2.51 g of 1,8-diazabicyclo[5.4.0]-7-undecene, followed by stirring for 3 hours at room temperature. After distilling off the solvent, the residue thus obtained was subjected to silica gel column chromatography using a n-hexane/ethyl acetate mixture as an elution solvent, thereby obtaining 6.06 g of ethyl 2-[4-[((3S)-1-tert-butoxycarbonyl-3-pyrrolidinyl)oxy]phenyl]-3-(7-cyano-2-naphthyl)acrylate as a mixture of E and Z forms. A portion of the thus obtained compound was separated into E and Z forms.

Provenance & Evidence