Related Experiment Video
Updated: Sep 7, 2025
08:12
Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
Published on: December 16, 2022
3.4K
Controlled Alternating Metathesis Copolymerization of Terminal Alkynes
Subhajit Pal1, Indradip Mandal1, Andreas F M Kilbinger1
1Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland.
ACS Macro Letters
|June 23, 2022
Summary
This study demonstrates controlled alternating copolymerization of terminal alkynes with 2,3-dihydrofuran using a Grubbs
Area of Science:
- Polymer Chemistry
- Organic Chemistry
- Materials Science
Background:
- Terminal alkynes exhibit high reactivity with ruthenium-carbene metathesis catalysts, but their homopolymerization is hindered by bulky carbene formation.
- Inefficient cross-propagation between terminal alkynes and less-hindered cycloalkenes limits their copolymerization.
- Terminal alkynes readily undergo cross-metathesis with vinyl ethers, suggesting potential for efficient copolymerization with cyclic enol ethers.
Purpose of the Study:
- To develop an efficient alternating copolymerization method for terminal alkynes and cyclic enol ethers.
- To investigate the controlled nature of the copolymerization process.
- To explore the utility of the synthesized copolymers for polymer conjugation and degradation.
Main Methods:
- Alternating copolymerization of terminal alkyne derivatives with 2,3-dihydrofuran using Grubbs' third-generation catalyst (G3).
- Characterization of copolymer molecular weight and structure using Size Exclusion Chromatography (SEC) and Nuclear Magnetic Resonance (NMR) spectroscopy.
- Exploitation of regioselective chain transfer and carbene reactivity for polymer conjugation.
- Assessment of copolymer degradation in the presence of an acid-labile backbone functionality.
Main Results:
- Achieved controlled alternating copolymerization of terminal alkynes and 2,3-dihydrofuran, confirmed by linear molecular weight dependence on monomer-to-initiator ratio and block copolymer synthesis.
- SEC and NMR analyses demonstrated excellent control over molecular weight and exclusive alternating copolymer structure.
- Successfully utilized regioselective chain transfer and carbene reactivity for polymer conjugation.
- Synthesized alternating copolymers with an acid-labile backbone exhibited rapid degradation.
Conclusions:
- Grubbs' third-generation catalyst enables controlled alternating copolymerization of terminal alkynes with 2,3-dihydrofuran.
- The synthesized alternating copolymers offer precise molecular weight control and possess an acid-labile backbone for tunable degradation.
- The methodology is suitable for polymer conjugation applications.
More Related Videos
07:28Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
13.3K
09:35Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
11.6K
Related Concept Videos
01:13Olefin Metathesis Polymerization: Overview
2.2K
Recently, the development of olefin metathesis polymerization advanced the field of polymer synthesis. Simply put, the reorganization of substituents on their double bonds between two olefins in the presence of a catalyst is known as the olefin metathesis reaction. The use of metathesis reaction for polymer synthesis is called olefin metathesis polymerization.
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists...
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists...
2.2K
00:53Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)
2.0K
Acyclic diene metathesis polymerization or ADMET polymerization involves cross-metathesis of terminal dienes, such as 1,8-nonadiene, to give linear unsaturated polymer and ethylene. As ADMET is a reversible process, the formed ethylene gas must be removed from the reaction mixture to complete the polymerization process.
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...
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...
2.0K
02:27Preparation of Alkynes: Alkylation Reaction
10.6K
Introduction
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.
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.
10.6K
02:35Free-Radical Chain Reaction and Polymerization of Alkenes
8.1K
The conversion of alkenes to macromolecules called polymers is a reaction of high commercial importance. The structure of the polymer is defined by a repeating unit, while the terminal groups are considered insignificant. The average degree of polymerization represents the number of repeating units in the polymer molecule and is denoted by the subscript n.
8.1K
01:16Olefin Metathesis Polymerization: Ring-Opening Metathesis Polymerization (ROMP)
2.7K
Ring-opening metathesis polymerization or ROMP involves strained cycloalkenes as starting materials. The mechanism of ROMP proceeds by reacting cycloalkene with Grubbs catalyst to give metallacyclobutane intermediate which undergoes a ring-opening reaction to form new carbene. The new carbene reacts with another molecule of cycloalkene. Repetition of these steps leads to the formation of an unsaturated open-chain polymer product. All these steps are reversible, however, relieving the ring...
2.7K
02:47Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
18.9K
Introduction
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
18.9K