Click here to sign in with

or

Forget Password?

Learn more

September 8, 2020

by Wiley

Carbon dioxide (CO2) is not just an undesirable greenhouse gas, it is also an interesting source of raw materials that are valuable and can be recycled sustainably. In the journal Angewandte Chemie, Spanish researchers have now introduced a novel catalytic process for converting CO2 into valuable chemical intermediates in the form of cyclic carbonates.

googletag.cmd.push(function() { googletag.display(‘div-gpt-ad-1449240174198-2’); });

Getting CO2 to react is unfortunately not easy. Currently, most research is focused on the conversion of CO2 into methanol, which can be used as an alternative fuel as well as a feedstock for the chemical industry. Innovative catalytic processes could allow CO2 to be converted into valuable chemical compounds without taking a detour through methanol, perhaps for the production of biodegradable plastics or pharmaceutical intermediates.

One highly promising approach is the conversion of CO2 into organic carbonates, which are compounds that contain a building block derived from carbonic acid, comprising carbon atom attached to three oxygen atoms. Researchers working with Arjan W. Kleij at the Barcelona Institute of Science and Technology (Barcelona), the Institute of Chemical Research of Catalonia (Tarragona), and the Catalan Institute of Research and Advanced Studies (Barcelona), have developed a conceptually new process to produce carbonates in the form of six-membered rings, starting from CO2 and basic, easily accessible building blocks. These cyclic carbonates have great potential for the creation of new CO2-based polycarbonates.

The starting materials are compounds with a carbon-carbon double bond and an alcohol group (-OH) on a neighboring carbon atom (homoallylic alcohols). In the first step of the reaction, the double bond is converted into an epoxide, a three-membered ring with one oxygen and two carbon atoms. The epoxide is able to react with CO2 in the presence of a specific catalyst. The product is a cyclic carbonate in the form of a five-membered ring with three carbon and two oxygen atoms. The carbon atom at the “tip” of the five-membered ring is attached to an additional oxygen atom. In the next step, an organic catalyst (N-heterocyclic base) activates the OH group and causes the five-membered ring to rearrange into a six-membered ring. The oxygen atom from the OH group is integrated into the new ring, while one of the oxygen atoms from the original five-membered ring forms a new OH group. However, the reverse reaction also takes place because the original five-membered ring is significantly more energetically favorable, and only a vanishingly small amount of the six-membered ring is present at equilibrium. The trick is to trap the six-membered ring. The new OH group binds to a reagent (acylation) because its different position makes it considerably more reactive than the original OH group.

This newly developed process gives access to a broad palette of novel, six-membered carbonate rings in excellent yields, with high selectivity and under mild reaction conditions. This widens the repertoire of CO2-based heterocycles and polymers, which are difficult to produce by conventional methods.

Thank you for taking your time to send in your valued opinion to Science X editors.

You can be assured our editors closely monitor every feedback sent and will take appropriate actions. Your opinions are important to us.

We do not guarantee individual replies due to extremely high volume of correspondence.

Your email address is used only to let the recipient know who sent the email. Neither your address nor the recipient’s address will be used for any other purpose.
The information you enter will appear in your e-mail message and is not retained by Phys.org in any form.

Get weekly and/or daily updates delivered to your inbox.
You can unsubscribe at any time and we’ll never share your details to third parties.

This site uses cookies to assist with navigation, analyse your use of our services, and provide content from third parties.
By using our site, you acknowledge that you have read and understand our Privacy Policy
and Terms of Use.

Source: https://phys.org/news/2020-09-cascades-carbon-dioxide.html

Carbon dioxide, Chemistry, Greenhouse gas

World news – US – Cascades with carbon dioxide

En s’appuyant sur ses expertises dans les domaines du digital, des technologies et des process , CSS Engineering vous accompagne dans vos chantiers de transformation les plus ambitieux et vous aide à faire émerger de nouvelles idées, de nouvelles offres, de nouveaux modes de collaboration, de nouvelles manières de produire et de vendre.

CSS Engineering s’implique dans les projets de chaque client comme si c’était les siens. Nous croyons qu’une société de conseil devrait être plus que d’un conseiller. Nous nous mettons à la place de nos clients, pour aligner nos incitations à leurs objectifs, et collaborer pour débloquer le plein potentiel de leur entreprise. Cela établit des relations profondes et agréables.

Nos services:

  1. Création des sites web professionnels
  2. Hébergement web haute performance et illimité
  3. Vente et installation des caméras de vidéo surveillance
  4. Vente et installation des système de sécurité et d’alarme
  5. E-Marketing

Toutes nos réalisations ici https://www.css-engineering.com/en/works/

LEAVE A REPLY

Please enter your comment!
Please enter your name here