Featured Research

from universities, journals, and other organizations

Chemists Create Class Of Carbenes Used To Make Catalysts

Date:
December 14, 2009
Source:
University of California - Riverside
Summary:
Researchers have successfully created in the laboratory a class of carbenes used to make catalysts. Until now, chemists believed these carbenes, called "abnormal N-heterocyclic carbenes" or aNHCs, were impossible to make. The aNHCs are stable at room temperature both in the solid state and in solution, which means their application as metal-free catalysts is extremely wide, greatly benefiting industry by making possible scores of new chemical reactions.

Molecular structure of the C5-Abnormal N-Heterocyclic Carbene (blue: nitrogen atoms; violet: abnormal carbene carbon atom; gray: normal carbon atoms).
Credit: Bertrand lab, UC Riverside

Researchers at the University of California, Riverside have successfully created in the laboratory a class of carbenes, highly reactive molecules, used to make catalysts -- substances that facilitate chemical reactions. Until now, chemists believed these carbenes, called "abnormal N-heterocyclic carbenes" or aNHCs, were impossible to make.

Carbenes are made up of unusual carbon atoms and are usually unstable in nature. They attach themselves to metals to form metal-carbene complexes that serve as efficient catalysts used widely in the pharmaceutical industry.

The metal-carbene complexes are formed in two ways: (a) the complex is created in one step, without first preparing carbene independently, and (b) a metal and an independent carbene are brought together to make the complex.

Most often the metal used in a metal-carbene complex is rhodium, gold, platinum or palladium -- all of which are very expensive and, in some cases, even toxic. To bring down the cost of catalysts, when possible, carbenes are used independently (without metals) in many chemical reactions.

Until now, aNHCs have been used as only metal-carbene complexes, never independently. Chemists had assumed that aNHCs cannot exist freely, which made them impossible to make.

Now UC Riverside's Guy Bertrand, a distinguished professor of chemistry, and colleagues have challenged that assumption by successfully creating aNHCs that are metal-free and can be used to make any desired complex.

"Many chemical species are believed to be unstable because they do not obey the rules we learned at school, and consequently nobody tries to make them," said Bertrand, who led the research project. "The role of scientists, however, is to challenge former hypotheses. That is just what we did in the case of the aNHCs, and we were successful.

"The aNHCs are stable at room temperature both in the solid state and in solution, which means their application as metal-free catalysts is extremely wide, greatly benefiting industry by making possible scores of new chemical reactions."

Results of the study appear in the Oct. 23 issue of Science.

"This study, reporting the synthesis and characterization of an entirely different class of metal-free NHCs, could open new horizons and have a huge impact on the field of catalysis," said John Schwab, who oversees organic synthesis grants at the National Institutes of Health's National Institute of General Medical Sciences. "The potential applications to drug discovery and manufacture are exciting, since catalytic processes can help keep costs in check and be environmentally friendly, to boot."

Bertrand is interested in making aNHCs commercially available. "We hope many chemists in the world will use these carbenes and find some new applications," he said.

The UCR Office of Technology Commercialization has filed a patent application on the technology and is currently seeking partners in industry interested in developing the technology commercially.

Bertrand was joined in the research by Eugenia Aldeco-Perez, Amos J. Rosenthal, and Bruno Donnadieu of UCR; and Gernot Frenking and Pattiyil Parameswaran of Phillips-Universitat Marburg, Germany.

The research project was funded by the National Institutes of Health. The National Council for Science and Technology (CONACYT), Mexico, provided Aldeco-Perez, the first author of the research paper, with financial support.


Story Source:

The above story is based on materials provided by University of California - Riverside. Note: Materials may be edited for content and length.


Cite This Page:

University of California - Riverside. "Chemists Create Class Of Carbenes Used To Make Catalysts." ScienceDaily. ScienceDaily, 14 December 2009. <www.sciencedaily.com/releases/2009/10/091022141119.htm>.
University of California - Riverside. (2009, December 14). Chemists Create Class Of Carbenes Used To Make Catalysts. ScienceDaily. Retrieved September 19, 2014 from www.sciencedaily.com/releases/2009/10/091022141119.htm
University of California - Riverside. "Chemists Create Class Of Carbenes Used To Make Catalysts." ScienceDaily. www.sciencedaily.com/releases/2009/10/091022141119.htm (accessed September 19, 2014).

Share This



More Matter & Energy News

Friday, September 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

MIT BioSuit A New Take On Traditional Spacesuits

MIT BioSuit A New Take On Traditional Spacesuits

Newsy (Sep. 19, 2014) The MIT BioSuit could be an alternative to big, bulky traditional spacesuits, but the concept needs some work. Video provided by Newsy
Powered by NewsLook.com
Virtual Reality Headsets Unveiled at Tokyo Game Show

Virtual Reality Headsets Unveiled at Tokyo Game Show

AFP (Sep. 18, 2014) Several companies unveiled virtual reality headsets at the Tokyo Game Show, Asia's largest digital entertainment exhibition. Duration: 00:48 Video provided by AFP
Powered by NewsLook.com
Apple's iOS8 Includes New 'Killswitch' To Curb Theft

Apple's iOS8 Includes New 'Killswitch' To Curb Theft

Newsy (Sep. 18, 2014) Apple's new operating system, iOS 8, comes with Apple's killswitch feature already activated, unlike all the models before it. Video provided by Newsy
Powered by NewsLook.com
Stocks Hit All-Time High as Fed Holds Steady

Stocks Hit All-Time High as Fed Holds Steady

AP (Sep. 17, 2014) The Federal Reserve signaled Wednesday that it plans to keep a key interest rate at a record low because a broad range of U.S. economic measures remain subpar. Stocks hit an all-time high on the news. (Sept. 17) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins