Release Subtitle: Scientists report the first instance of an
electrochemical reaction that produces thienoacenes, useful materials
used in organic semiconductors
Release Summary Text:
In the field of electronics, developing novel strategies for organic
semiconductor synthesis are crucial. Derivatives of compounds called
“thienoacenes” have been known for their role as organic semiconductors,
but conventional methods for the synthesis of thienoacenes require the
use of expensive transition metal catalysts. To overcome this
limitation, scientists at Okayama University developed a novel
electrochemical reaction that successfully produced thienoacene
derivatives in a cost-effective manner.
Full text of release:
Organic solar cells have a variety of applications in the field of
electronics, especially in the development of novel electronic devices
like wearable devices. Often, these batteries are composed of organic
semiconductor molecules, which are light and robust. Thus, finding novel
strategies for the development of these semiconductor molecules has
been the goal of many scientists globally. But usually, synthesizing
these molecules involves the use of expensive rare metal catalysts. Not
only does this result in a high manufacturing cost, but the possibility
of the metal catalysts being contaminated makes the process challenging.
To this end, in a new study published in Angewandte Chemie International
Edition, a research group at Okayama University, including Professor
Seiji Suga and Associate Professor Koichi Mitsudo, developed a novel
reaction system to synthesize thienoacene derivatives—key building
blocks in organic semiconductor synthesis. The scientists focused on
constructing carbon–sulfur (C–S) bonds through organic electrolysis,
which is an environment-friendly reaction. Prof Suga explains, “We
focused on C–S bonds, as they are an abundant and significant in the
field of pharmaceuticals and materials science, such as in certain
antidepressant and antifungal medications. ”
Conventionally, C–S bonds are constructed via a method called
“transition metal-catalyzed cross-coupling,” which requires the use of
rare metal catalysts. This makes the reaction expensive and, thus,
infeasible. Thus, in this study, the scientists focused on a different
approach, called “electrochemical carbon-heteroatom bond formation,”
which is an eco-friendly reaction requiring mild conditions. Although
several novel electrochemical carbon-heteroatom coupling reactions have
been reported in the past, these reactions had never been used to
synthesize thienoacenes until now. Prof Suga says, “Over the past
several years, we were interested in the development of new methods for
thienoacene synthesis, acene derivatives that have a good track record
in organic electrochemistry and are attractive candidates for useful
organic materials .”
Having established the basis of their study, the scientists then dug
deeper to find novel electrochemical methods for thienoacene synthesis.
They found that the desired C–S bond formation occurred smoothly in the
presence of a “bromide” ion, which acts as a powerful promoter of the
reaction. Using this strategy, the scientists successfully synthesized
types of thienoacene derivatives called the “π-expanded thienoacene
derivatives.” Interestingly, this study is the first to report
successful C–S bond formation for the synthesis of thienoacene
derivatives. Prof Suga explains, “Our study was the first to report an
electro-oxidative dehydrogenative reaction to produce C–S bonds for
thienoacenes. We found that bromide ion, which catalytically promotes
the reaction as a halogen mediator, is essential to the reaction .”
This study offers hope that, in the future, organic semiconductor
molecules can be produced using a cost-efficient technique, without the
need to use expensive metal catalysts. Prof Suga concludes, “The key to
this research lies in the method of ‘electrochemical synthesis,’ which
is a clean and renewable source of energy .” Through these findings, the
scientists at Okayama University hope to achieve sustainable organic
synthesis with minimal impact on the environment. Thus, this study is
also a significant step towards achieving the UN sustainable development
goals and hence promoting a better future for humanity.
Release URL: https://www.eurekalert.org/pub_releases/2020-06/ou-nee060720.php
Reference:
Title of original paper: Electrochemical Synthesis of Thienoacene
Derivatives: Transition Metal-Free Dehydrogenative C–S Coupling Promoted
by a Halogen Mediator
Journal: Angewandte Chemie International Edition
DOI: http://dx.doi.org/10.1002/anie.202001149
Contact Person: SUGA Seiji
E-mail: suga(a)cc.okayama-u.ac.jp
For inquiries, please contact us by replacing (a) with the @ mark.
Website: http://achem.okayama-u.ac.jp/reacteng/
0 件のコメント:
コメントを投稿