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Published on: November 21, 2017
Polyolefin cyclization triggered by electrochemically generated alkoxycarbenium ions: batch and flow conditions.
Andraž Oštrek1, Yosuke Ashikari2, Cristiano Cassinera1
1Department of Chemistry, University of Pavia Viale Taramelli 10 Pavia 27100 Italy gz@unipv.it.
Chemical Science
|July 8, 2026
Summary
Electrochemical carbocations initiate polyolefin cascade cyclizations. This flow chemistry method rapidly generates cationic species for efficient synthesis of complex polycyclic products from aryl dienes.
Area of Science:
- Organic Chemistry
- Polymer Chemistry
- Flow Chemistry
Background:
- Cascade cyclizations are powerful tools for constructing complex molecular architectures.
- Initiation of polyolefin cascade cyclizations often requires harsh conditions or specific reagents.
- Electrochemical generation of reactive intermediates offers a tunable and potentially milder alternative.
Purpose of the Study:
- To investigate the use of electrochemically generated carbocations as initiators for intermolecular polyolefin cascade cyclizations.
- To optimize reaction conditions for efficient cascade cyclization under flow conditions.
- To demonstrate the versatility of the developed method for synthesizing diverse polycyclic compounds.
Main Methods:
- Utilized the cation pool method to assess the feasibility of carbocation-initiated cascade cyclizations.
- Developed a low-temperature flash generation technique for cationic species in a flow reactor.
- Performed rapid in-flow cascade cyclization reactions followed by product isolation and characterization.
Main Results:
- Successfully employed electrochemically generated carbocations to initiate intermolecular polyolefin cascade cyclizations.
- Optimized flow conditions enabled efficient generation of cationic species and subsequent rapid cyclization.
- Synthesized various polycyclic products from different aryl diene substrates using the developed flow setup.
Conclusions:
- Electrochemical generation of carbocations is a viable strategy for initiating polyolefin cascade cyclizations.
- The developed flow chemistry approach allows for rapid and efficient synthesis of polycyclic compounds.
- This method offers a promising alternative for constructing complex molecular structures under controlled conditions.
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