Ruthenium alkylidene-catalyzed reaction of 1,6-heptadiynes with alkenes
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Updated: Apr 17, 2026

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Silvia Alvarez1, Sandra Medina, Gema Domínguez
1Facultad de Farmacia, Departamento Química y Bioquímica, Universidad San Pablo CEU , Urb. Montepríncipe, ctra. Boadilla km 5,300 Boadilla del Monte, 28668 Madrid, Spain.
Abstract:
Ruthenium carbene catalysts are able to catalyze cross [2 + 2 + 2] cyclotrimerizations of 1,6-diynes with cyclic and acyclic double bonds. A plausible mechanistic competition is described in which electron-deficient alkenes follow similar pathways as those of other ruthenium catalysts previously utilized and produce mixtures of trienes and cyclohexadienes. On the contrary, allylethers give different isomers of the same final products, suggesting that a metathetic cascade pathway operates in these cases.
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