Alkene Cross‐Metathesis with 2,5‐Dimethyl‐2,4‐Hexadiene Enables Isobutylenyl/Prenyl Functionalizations and Rubber Valorization

2,5‐Dimethyl‐2,4‐hexadiene is a readily available and easily managable compound, whose symmetric and polymethylated dienic structure should be prone to engage in cross‐metathesis reactions with other alkenes, but this has not been apparently exploited so far. Here we show that this reactant enables...

Full description

Saved in:
Bibliographic Details
Published in:Chemistry : a European journal 2024-07, Vol.30 (37), p.e202400860-n/a
Main Authors: Mingueza‐Verdejo, Paloma, Rodríguez‐Nuévalos, Silvia, Oliver‐Meseguer, Judit, Leyva‐Pérez, Antonio
Format: Article
Language:English
Subjects:
2,5-Dimethyl-2,4-hexadiene
Alkene cross-metathesis
Alkenes
and Isobutenyl
Catalysts
Decomposition reactions
Hexadiene
Isoprene
Metathesis
Polymers
Prenylation
Rubber
Rubber valorization
Citations: Items that this one cites
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:2,5‐Dimethyl‐2,4‐hexadiene is a readily available and easily managable compound, whose symmetric and polymethylated dienic structure should be prone to engage in cross‐metathesis reactions with other alkenes, but this has not been apparently exploited so far. Here we show that this reactant enables the easy synthesis of tri‐ and tetra‐susbtituted alkenes (i. e. isobutylenyl and prenyl groups) from simple alkenes under mild reaction conditions, not only with the conventional 2nd generation Grubbs catalyst but also with other Grela‐type catalyts such as StickyCat,TM AquaMetTM and GreenCatTM. The use of liquid and low volatile 2,5‐dimethyl‐2,4‐hexadiene avoids the use of gaseous alkene reactants and, besides, showcases the reactivity of polyisoprene (rubber), thus allowing to optimize the reaction conditions for rubber upcycling, after metathesis reaction of the pristine or used polymer with simple alkenes. These results bring low volatile isoprene‐type compounds as privileged poly‐substituted reactants for alkene cross‐metathesis reactions. 2,5‐Dimethyl‐2,4‐hexadiene is presented here as a suitable and selective reactant for delivering either prenyl or isobutylenyl groups to alkenes through a cross‐metathesis reaction. The process smoothly operates at room temperature, give high yields of products, includes a late‐stage transformation, and enables the valorization of real samples of recycled rubber.
ISSN:0947-6539
1521-3765
1521-3765
DOI:10.1002/chem.202400860