Selective Synthesis of “Left-Handed” or “Right-Handed” Chemicals

Highlight Date: 
08/30/2013
Display Section: 
Division of Chemical and Biological Sciences
Broad Audience Highlights
Article Title: 
Highly Enantioselective Zirconium-Catalyzed Cyclization of Aminoalkenes
Author(s): 
K. Manna, W. C. Everett, G. Schoendorff, A. Ellern, T. L. Windus, and A. D. Sadow
Article Link: 
Journal Name: 
Journal of the American Chemical Society
Volume: 
135
Year: 
2013
Page Number(s): 
7235-7250
Highlight Text: 

A new series of catalysts is able to selectively make “left-handed” or “right-handed” nitrogen-containing compounds known as amines. Left-handed and right-handed molecules contain the same components, but are mirror images of each other. Researchers were able to take strings of nitrogen-containing molecules and make five-, six- and seven-membered rings with enantiomeric excess of 90%.  Most other catalysts produce a mixture of both enantiomers.  Researchers studied hafnium, titanium and zirconium (Group 4) containing catalysts and found the zirconium catalysts to be the best at producing one enantiomer in high yield over the other.  The new zirconium catalysts do what no other Group 4 catalyst has done before — they can operate at room temperature and down to minus 20 °F.  All other zirconium catalysts operate at 300 °F.  These new catalysts are also tolerant of various functional groups attached to the amines. Researchers performed detailed studies of the structure, activity and selectivity of this system of catalysts and were able to characterize the reaction pathways. The pursuit of these optically active amines is important for improved syntheses of commodity and specialty chemicals. 

Even though its research is already underway, the Critical Materials Institute will be officially launched with a grand opening celebration on Tuesday, Sept. 10 on the front steps of Willhelm Hall. The CMI is one of the Department of Energy's Energy Innovation Hubs and the event will include speakers from DOE, Ames Laboratory, Iowa State University and the CMI.

The event, scheduled to begin at 10 a.m., will feature speeches by representatives of the various groups mentioned and an official ribbon cutting ceremony. DOE will be represented by David Danielson, Assistant Secretary, Energy Efficiency & Renewable Energy. Ames Lab Interim Director Tom Lograsso, Iowa State University President Steven Leath and CMI Director Alex King are also scheduled to speak.

Following the ceremony, a lunch for invited guests will be held in a tent to be set up in the south end of the parking lot in front of TASF. Information on parking will be provided next week. Pammel Drive will also be closed during the dedication event.

"We first started working on this back in January of 2011," King said, "so it has taken a while to come to fruition. It's evidence that hard work pays off ... and the reward is more hard work. So be careful what you wish for."

"I think it was Winston Churchill who said, 'This isn't the end. In fact, it's not even the beginning of the end. But it might be considered the end of the beginning'" King said. "We're excited to get started."

The grand opening festivities are just the start of two and a half days of meetings for the Institute. Staff from all of the CMI's 18 partner institutions - four national labs, seven universities and seven industrial partners - will be on hand. Tuesday afternoon and Wednesday morning, there will be plenary sessions that are open to Ames Lab and ISU staff. The balance of the meetings will be closed and focus on specific research efforts. The plenary sessions will be held in the Spedding Hall auditorium, 301 Spedding.

The CMI was created to develop solutions to domestic shortages of rare earth metals and other materials vital to U.S. energy security. These materials are essential in many modern clean energy technologies – such as wind turbines, solar panels, electric vehicles, and energy-efficient lighting.

DOE announced in January that the Ames Laboratory had been selected to lead the Critical Materials Institute with federal funding of $120 million over five years. The hub is a collaboration of leading researchers from academia, four DOE national laboratories, and the private sector.

Energy Innovation Hubs are major integrated research centers with researchers from many different institutions and technical backgrounds that combine basic and applied research with engineering to accelerate scientific discovery in critical energy areas. The CMI is only the fifth such Hub to be launched by DOE.

Image
The main reception area in the CMI office on first floor Willhelm gets some finishing touches.
Image
Workmen (green shirts) were installing the main door while technicians from Storey-Kenworthy (blue shirts) installed furniture fixtures.
Image
Cabinetry throughout the space, including the kitchenette, has been installed but the countertop contractor hasn't completed the job.

Ames Laboratory will be boosting its characterization capabilities when it acquires a Dynamic Nuclear Polarization-NMR spectrometer The new equipment represents a giant step forward in the laboratory’s world-class solid state NMR capabilities.

The Ames Laboratory’s instrument will be the first of its kind to be focused on materials and materials chemistry in the United States.

In traditional nuclear magnetic resonance (NMR) technology, researchers are able to discover physical, chemical, electronic, and structural information about materials, based on the way atomic nuclei in the sample absorb electromagnetic radiation in a strong magnetic field.

Dynamic Nuclear Polarization (DNP)-NMR uses microwaves to polarize electrons, and then transfer that polarization from the electrons to the nuclei of the sample being analyzed.

“It’s essentially a combination of two techniques, electron paramagnetic resonance (EPR) spectroscopy with NMR, which yields an amazing increase in sensitivity,” said Cynthia Jenks, assistant director of scientific planning for the Ames Laboratory and director of chemical and biological sciences. “In the types of materials we use, we’ve been able to demonstrate an enhancement of anywhere from eight to 30 times in signal sensitivity. Results that used to take a week to obtain will now take hours or minutes.”

The increased capabilities of the DNP-NMR instrument will be in the hands of the lab’s six world-leading solid-state NMR scientists, and opens up possibilities for research that didn’t previously exist.

Image
Dynamic Nuclear Polarization (DNP)-NMR combines two techniques, electron
paramagnetic resonance (EPR) spectroscopy with NMR, producing more sensitive,
rapid research results. Photo courtesy of Bruker.

“Needless to say, we are all very pleased with this acquisition”, said Marek Pruski, the principal investigator of the research team. “The Ames Laboratory has an elite group of scientists specializing in the development and applications of solid-state NMR techniques. During the last 2 years we have conducted exploratory studies to demonstrate the critical importance of DNP NMR to our materials chemistry research, using the existing instrument in Lausanne, Switzerland and at the Bruker facility in Billerica, Massachusetts. All these factors, and the critical support from the Ames Laboratory leadership made this outcome possible.”

Laboratory scientists expect the instrument to greatly expand and accelerate the progress of research efforts in many areas, including catalysis, nanocomposites, fuel cell membrane materials, soil organic matter, carbon electrode  materials, plant cell walls, hydrogen storage materials, and complex states.

The concept of DNP-NMR was first theorized and demonstrated in the 1950s at the University of Illinois, but it took decades of progress in microwave and NMR technology, mainly at MIT, to make a commercially produced instrument possible, only in the last three years.

The instrument, manufactured by Bruker, will be delivered and installed next year.  The instrument is funded by DOE’s Office of Science,  which supports fundamental research to understand, predict, and ultimately control matter and energy at the electronic, atomic, and molecular levels, in an effort to provide the foundations for new energy technologies and to support DOE missions in energy, environment, and national security.

Occupational Medicine staff will administer flu shots from 10 a.m. to 4 p.m. Oct. 7 through Oct. 18 in 205 Technical Administrative Service Facility (TASF).  No appointment is necessary.  Be sure to bring your ISU ID card or your university ID number to the shot clinic. Please note there is limited parking in front of TASF.

Flu shots will be provided at no cost for the following eligible groups:

  • Faculty
  • Merit
  • Professional and Scientific
  • University Child Care (ISU employees only)
  • Miscellaneous affiliate employees enrolled in ISU health plans (ISU Foundation, Iowa State Daily, Greek house directors).  Some affiliate organizations will need to pay for their participating employees' vaccinations.
  • Retirees on university health plans who are not yet 65 

Students, post docs and visiting scholars are not eligible to receive flu shots at the clinic in TASF.  These individuals should contact the Thielen Student Health Center, 4-5801, for flu vaccine information.

Employees are encouraged to get vaccinated as soon as possible within the specified October time frame. For more information, call 4-0874.

Graphene for metamaterials

Could graphene – a one-layer thick sheet of carbon atoms – be the ingredient needed for super-efficient solar harvesting with metamaterials? Or for “light on wire” plasmonic data transmission? In the Aug. 9 issue of Science, Ames Laboratory physicists Costas Soukoulis, Philippe Tassin, and Thomas Koschny discuss the potential and challenges of using graphene in metamaterials and plasmonics in terahertz applications, which operate at frequencies between microwave and infrared waves.

Metamaterials are man-made structures that exhibit properties not possible in natural materials, such as refracting light “backward” or absorbing all the light that hits them.The Ames Lab trio found that graphene may be a good candidate to replace the metals currently used to build metamaterials.

“Graphene is a fascinating and promising material because it’s so thin, is very electronically responsive, and has electronic properties that are easily changed,” said Soukoulis, Ames Laboratory physicist and Iowa State University Distinguished Professor of physics and astronomy. “Our review of the findings shows hurdles to cross before graphene could replace the thin metal films currently used in metamaterials and plasmonics.”

“Graphene offers an advantage over metals because graphene’s properties can be more readily tuned to obtain the electrical response desired for a given application,” said Soukoulis.

Graphene’s tunability may also make it a good candidate for use in plasmonics, where a tiny structure uses light to carry information.

However, Soukoulis, Tassin and Koschny still see challenges. They surveyed both experimental measurements and theoretical simulations about graphene’s properties relevant for terahertz applications. In general, Soukoulis’ team noted that the data indicate a “discrepancy between the experimentally realizable and the theoretically predicted performance.” For instance, experimental data have shown significantly higher electrical losses than has been estimated by theoretical work.

“Overcoming those dissipative losses will be the major obstacle for using graphene in terahertz applications of metamaterials and plasmonics,” said Soukoulis.

Soukoulis, Tassin and Koschny’s work at Ames Laboratory was supported by the U.S. Department of Energy’s Office of Science (funding for the search for better optical materials, properties of metals at optical frequencies, and understanding electrical losses in metamaterials) and the U.S. Office of Naval Research (graphene as conductors for resonant metamaterials). Iowa State University College of Liberal Arts Frances M. Craig Professorship also supports Soukoulis’ efforts.

ESH&A Walk-About 08-10-12

Department: 
Environment Safety Health Assurance
Document Upload: 
Effective Date: 
Aug. 2012
Version Number: 
NA
Document Number: 
NA

ESH&A Walk-About 09-30-11

Department: 
Environment Safety Health Assurance
Document Upload: 
Effective Date: 
Sep. 2011
Version Number: 
NA
Document Number: 
NA

Quality Assurance Program (QAP) Awareness Training

Department: 
Training
Effective Date: 
NA
Version Number: 
NA
Document Number: 
NA

Occupational Medicine Program Review 02-20-13

Department: 
Occupational Medicine
Effective Date: 
Feb. 2013
Version Number: 
NA
Document Number: 
NA

Charter Department(s):

ESHA

Download Charter:

Effective date: NA

Version number: NA

Document Number: NA