Featured Research

from universities, journals, and other organizations

Chemists Identify Organic Molecules That Mimic Metals

Date:
April 20, 2007
Source:
University of California - Riverside
Summary:
Chemists at UC Riverside report that a class of carbenes -- molecules that have unusual, highly reactive carbon atoms -- can mimic, to some extent, the behavior of metals. The organic molecules could be used to develop carbon-based systems for storing hydrogen, and transform ammonia into amino compounds used to make pharmaceuticals and bulk industrial materials.

A cartoon representation of a carbene splitting hydrogen and ammonia.
Credit: G. Frey

A limitation in using hydrogen as a fuel in hydrogen-powered vehicles is the difficulty involved in storing it in a cost-effective and convenient manner. While it is possible to store hydrogen using metals, the resulting products often can be prohibitively expensive and cause environmental problems.

Chemists at UC Riverside now offer a possible solution. A class of carbenes -- molecules that have unusual, highly reactive carbon atoms -- can mimic, to some extent, the behavior of metals, the chemists have found. Called cyclic alkyl amino carbenes or CAACs, these organic molecules, the researchers report, could be used to develop carbon-based systems for storing hydrogen.

Study results appear in the April 20 issue of Science.

In their experiments, the researchers found that the CAACs can split hydrogen under extremely mild conditions, a behavior that has long been seen in metals reacting with hydrogen.

"The mode of action of these organic molecules, however, is totally different from that of metals," said Guy Bertrand, a distinguished professor of chemistry who led the research. "Moreover, the CAACs are able to split ammonia as well -- an extremely difficult task for metals."

Bertrand explained that such a splitting of ammonia, under certain conditions, can pave the way for transforming abundant and inexpensive ammonia into useful amino compounds used to make pharmaceuticals and bulk industrial materials. "This is one of the top challenges for the 21st century," he said.

According to the UCR research team, the metal-mimicking carbenes offer another low-cost and low-toxicity benefit: Scientists now may be able to use non-metallic catalysts for a reaction, called "hydrogenation reaction," which plays a critical role in the food, petrochemical and pharmaceutical industries.

In their study, the researchers exposed a solution of CAACs to both gaseous hydrogen and liquid ammonia. "We used nuclear magnetic resonance spectroscopy to analyze the products," said Guido Frey, the first author of the research paper and a postdoctoral fellow, supported by the Alexander von Humboldt Foundation, in Bertrand's lab. "And we used single crystal X-ray diffraction analysis to confirm the structure of the products."

A carbene is a molecule that has a carbon atom with six electrons instead of the usual eight. Because of the electron deficiency, carbenes are highly reactive and usually unstable in nature.

The National Science Foundation and Rhodia, Inc., provided support for the study. Bertrand and Frey were joined in the research by the following individuals at UCR: Vincent Lavallo, a graduate student; Bruno Donnadieu, a research associate supported by the Centre National de la Recherche Scientifique; and Wolfgang Schoeller, an adjunct professor of chemistry.


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 Identify Organic Molecules That Mimic Metals." ScienceDaily. ScienceDaily, 20 April 2007. <www.sciencedaily.com/releases/2007/04/070419140923.htm>.
University of California - Riverside. (2007, April 20). Chemists Identify Organic Molecules That Mimic Metals. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2007/04/070419140923.htm
University of California - Riverside. "Chemists Identify Organic Molecules That Mimic Metals." ScienceDaily. www.sciencedaily.com/releases/2007/04/070419140923.htm (accessed July 24, 2014).

Share This




More Matter & Energy News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

TSA Administrator on Politics and Flight Bans

TSA Administrator on Politics and Flight Bans

AP (July 24, 2014) TSA administrator, John Pistole's took part in the Aspen Security Forum 2014, where he answered questions on lifting of the ban on flights into Israel's Tel Aviv airport and whether politics played a role in lifting the ban. (July 24) Video provided by AP
Powered by NewsLook.com
Creative Makeovers for Ugly Cellphone Towers

Creative Makeovers for Ugly Cellphone Towers

AP (July 24, 2014) Mobile phone companies and communities across the country are going to new lengths to disguise those unsightly cellphone towers. From a church bell tower to a flagpole, even a pencil, some towers are trying to make a point. (July 24) Video provided by AP
Powered by NewsLook.com
Algonquin Power Goes Activist on Its Target Gas Natural

Algonquin Power Goes Activist on Its Target Gas Natural

TheStreet (July 23, 2014) When The Deal's Amanda Levin exclusively reported that Gas Natural had been talking to potential suitors, the Ohio company responded with a flat denial, claiming its board had not talked to anyone about a possible sale. Lo and behold, Canadian utility Algonquin Power and Utilities not only had approached the company, but it did it three times. Its last offer was for $13 per share as Gas Natural's was trading at a 60-day moving average of about $12.50 per share. Now Algonquin, which has a 4.9% stake in Gas Natural, has taken its case to shareholders, calling on them to back its proposals or, possibly, a change in the target's board. Video provided by TheStreet
Powered by NewsLook.com
Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) 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