Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Surprise shift

14.04.2009
A first-of-a-kind switch in chemical bonding by a zirconium atom spotted by scientists

A zirconium atom can switch easily between two different bonding patterns in an unusual molecule created by Japanese scientists.

The molecule’s odd behavior is the first example of this particular type of chemical bonding shift, according to Noriyuki Suzuki of RIKEN's Advanced Science Institute in Wako, and his colleagues at Saitama University and Saitama Institute of Technology. “These complexes have very unique structures and show interesting movement,” says Suzuki.

The team discovered the phenomenon when they were experimenting with a molecule (hexapentaene) made from a chain of six carbon atoms, all doubly bonded to each other. The chain is surrounded by a long cloud of delocalized electrons, which can bond with a zirconium-based compound to create a new complex.

Once the new complex has formed, the zirconium atom normally tends to bridge between carbon atoms in different parts of the chain, creating a five-membered ring. But when very bulky groups were added to each end of the chain, the zirconium switches its allegiance so that it sticks to just the central carbon–carbon double bond.

The complex could be toggled between its two bonding modes by adding or removing other chemical groups such as phosphines around the zirconium atom. Further experiments showed that this sort of shift was the first step in a reaction the scientists had previously studied, where adding an isocyanide chemical to the zirconium complex created a compound with a small ring of four carbon atoms at its heart.

This switching behavior is well known in certain ring-shaped organic molecules, but is much rarer in these molecular chains, and is unprecedented with this particular compound. “It suggests the possibility of a molecular motion like scissors or tongs,” says Suzuki. The research is published in the Journal of the American Chemical Society (1).

Suzuki’s team has spent several years investigating a range of such zirconium complexes, which were long assumed to be too unstable to isolate2,3.

Although there are no immediate applications for this family of complexes, Suzuki suggests that it may be possible to use the scissoring action identified in their latest research to capture another molecule or ion. “We might be able to achieve a molecular machine that catches a certain target,” says Suzuki.

Reference

1. Suzuki, N., Hashizume, D., Yoshida, H., Tezuka, M., Ida, K., Nagashima, S. & Chihara, T. Reversible haptotropic shift in zirconocene–hexapentaene complexes. Journal of the American Chemical Society 131, 2050-2051(2009) .

2. Suzuki, N., Nishiura, M. & Wakatsuki, Y. Isolation and structural characterization of 1-zirconacyclopent-3-yne, five-membered cyclic alkynes. Science 295, 660–663 (2002).

3. Suzuki, N., Hashizume, D., Koshino, H. & Chihara, T. Transformation of a 1-zirconacyclopent-3-yne, a five-membered cycloalkyne, into a 1-zirconacyclopent-3-ene and formal “1-zirconacyclopenta-2,3-dienes”. Angewandte Chemie International Edition 47, 5198–5202 (2008).

The corresponding author for this highlight is based at the RIKEN Chemical Analysis Team

Saeko Okada | Research asia research news
Further information:
http://www.rikenresearch.riken.jp/research/670/
http://www.researchsea.com

More articles from Life Sciences:

nachricht Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute

nachricht Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>