Versatile reaction could help greenhouse gas become a more useful synthetic chemical
RIKEN chemists have developed a catalyst that should allow carbon dioxide to be used as a versatile synthetic chemical.
Carbon dioxide (CO2) is produced whenever fossil fuels are burned, and it is a powerful greenhouse gas that traps heat in our atmosphere, contributing to global warming. As such, turning the gas into a chemical feedstock, rather than allowing it to escape into the atmosphere, is an extremely appealing idea.
In fact, industry has long used carbon dioxide as a chemical building block—in the manufacture of the painkiller aspirin, for example—but its use is limited by the difficulty of breaking open its strong carbon-oxygen double bonds.
Carbon compounds activated by lithium or magnesium are often needed to attack and incorporate carbon dioxide successfully, but these reagents are extremely reactive and quite hazardous on a large scale.
Chemists have recently developed milder, boron-based alternatives, which require a rhodium catalyst to speed up the reaction. Unfortunately, this catalyst tends to break down particularly sensitive chemical groups in the product.
Zhaomin Hou, of RIKEN's Advanced Science Institute, Wako, along with colleagues Takeshi Ohishi and Masayoshi Nishiura, has now developed a copper catalyst that helps the boron compounds to react with carbon dioxide without destroying sensitive chemical groups.
This makes the reaction particularly useful for building complex molecules containing several different types of chemical group, something that would not be possible with the harsh lithium reagents. “We have tried many different metal compounds, among which the copper catalyst was the best,” says Hou.
The team was also able to study exactly how the catalyst works, by isolating key molecules at various intermediate stages of the reaction. They found that the active copper catalyst first displaces the boron group from the starting molecule, forming a new copper–carbon bond. Carbon dioxide then inserts itself into this bond before the copper catalyst is finally removed, leaving behind a carboxylic acid (-CO2H) group1.
Various forms of the boron compounds, known as boronic esters, are commercially available, says Hou. “And they can also be easily prepared in the lab.”
Hou adds that their method is also amenable to large-scale, commercial synthesis. “Since CO2 is a renewable carbon resource, exploration of new reactions and catalysts for its efficient use is of great importance,” he says. “One of our goals is to find a catalyst that can transform CO2 in exhaust gasses of automobile vehicles or chemical plants into useful materials.”
1. Ohishi, T., Nishiura, M. & Hou, Z. Carboxylation of organoboronic esters catalyzed by N-heterocyclic carbene copper(I) complexes. Angewandte Chemie International Edition 47, 5792–5795 (2008)
The corresponding author for this highlight is based at the RIKEN Organometallic Chemistry Laboratory
Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute
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
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...
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...
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,...
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...
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...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy