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Updated: Jun 10, 2026
09:35
Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
A general route to fully terminally tert-butylated linear polyenes
Dagmar Klein1, Pinar Kiliçkiran, Cornelia Mlynek
1Institut für Organische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|July 29, 2010
Summary
Researchers synthesized highly stable, conjugated polyolefins with up to 13 double bonds using McMurry dimerization or Wittig chain-elongation. These novel π systems are suitable for further chemical reactivity studies.
Area of Science:
- Organic Chemistry
- Polymer Science
- Materials Science
Background:
- α,β-unsaturated ketones are versatile starting materials in organic synthesis.
- Conjugated polyolefins with extended π systems are of interest for their unique electronic and optical properties.
Purpose of the Study:
- To synthesize novel, terminally tert-butylated polyolefins with extended conjugated double bond systems.
- To investigate the stability and structural characteristics of these highly unsaturated π systems.
- To prepare sufficient quantities for future chemical reactivity studies.
Main Methods:
- Synthesis of higher vinylogues and polyolefins starting from 3-tert-butyl-4,4-dimethyl-2-pentenal.
- Utilizing McMurry dimerization and Wittig chain-elongation reactions for chain extension.
- Characterization using spectroscopic methods (e.g., NMR, UV-Vis) and X-ray structural analysis.
Main Results:
- Successful preparation of polyolefins with up to 13 consecutive conjugated double bonds.
- Demonstration of remarkable stability in these highly unsaturated conjugated π systems.
- High yields achieved, facilitating further chemical investigations.
Conclusions:
- The study presents a viable synthetic route to novel, stable, and highly conjugated polyolefins.
- The synthesized compounds offer a platform for exploring the chemistry of extended π systems.
- The accessibility and stability of these materials open avenues for advanced applications.
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