(R)-Methyl 2-((tert-butoxycarbonyl)amino)pent-4-enoate → methyl(2R,4E)-4-[(2R)-1-{[{(1R)-1-[3,5-bis(trifluoromethyl)phenyl]ethyl}(methyl)amino]carbonyl}-2-(4-fluoro-2-methylphenyl)-4-piperidinylidene]-2-({[(1,1-dimethylethyl)oxy]carbonyl}amino)butanoate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of (2R)-N-{(1R)-1-[3,5-bis(trifluoromethyl)phenyl]ethyl}-2-(4-fluoro-2-methylphenyl)-N-methyl-4-methylidene-1-piperidinecarboxamide (intermediate 53 3 g, 5.97 mmol) and methyl (2R)-2-({[(1,1-dimethylethyl)oxy]carbonyl}amino)-4-pentenoate (4.11 g, 17.91 mmol) in dry, degassed dichloromethane (DCM) (24 ml), was added to a flame dried round bottomed flask containing (1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene)dichloro(o-isopropoxyphenylmethylene)ruthenium, Hoveyda-Grubbs catalyst 2nd generation, (0.187 g, 0.299 mmol) under a nitrogen atmosphere. The green mixture was stirred and heated at reflux for 30 h (T bath=47° C.).

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