Related Experiment Video
Updated: May 29, 2026

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
Ethylene-promoted versus ethylene-free enyne metathesis
Anne G D Grotevendt1, Justin A M Lummiss, Melanie L Mastronardi
1Department of Chemistry; Centre for Catalysis Research & Innovation, University of Ottawa, Ottawa, ON, Canada K1N 6N5.
Abstract:
The role of ethylene in promoting metathesis of acetylenic enynes is probed within the context of ring-closing enyne metathesis, using first- and second-generation Grubbs catalysts. Under inert atmosphere, rapid catalyst deactivation is observed by calibrated GC-FID analysis for substrates with minimal propargylic bulk. MALDI-TOF mass spectra reveal a Ru(enyne)(2) derivative that exhibits very low reactivity toward both enyne and ethylene. Under ethylene, formation of this species is suppressed. Enynes with bulky propargylic groups are not susceptible to this catalyst deactivation pathway, even under N(2) atmosphere.
Related Concept Videos
Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
Olefin Metathesis Polymerization: Overview
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists of a...
Cycloaddition Reactions: MO Requirements for Photochemical Activation
Free-Radical Chain Reaction and Polymerization of Alkenes
Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
Preparation of Alkynes: Alkylation Reaction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
