NEWS OF THE W EEK
U.S. WINS TRADE TIFF WITH CHINA
China must lift restraints on exports of key industrial raw materials such as fluorspar, WTO says. M ADE-IN -CHIN A.CO M
RAW MATERIALS: Panel says China unfairly limits export of components for manufacturing
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HINA’S EXPORT DUTIES and quotas on several
raw materials widely used in the chemical, steel, and aluminum industries violate international rules that it has agreed to follow since 2001, a panel of the World Trade Organization ruled last week. China potentially faces sanctions if it does not correct the violations. The WTO panel largely agreed with complaints filed in 2009 by the U.S., the European Union, and Mexico, which alleged that the export restrictions allowed the Chinese government to artificially increase world prices for the materials by constraining supplies while giving the country’s domestic producers an unfair competitive advantage. As a member nation of WTO, China must now “bring its export duty and export quota measures into conformity,” the panel said. The raw materials at issue in the case included various forms of bauxite, coke, fluorspar,
IRONING OUT ALKENE HYDROSILYLATION CATALYSIS: Iron compound could supplant more expensive catalysts
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HEMISTS COULD SOON have a cheaper way
to make silicone-based surfactants, fluids, release coatings, and pressure-sensitive adhesives, thanks to an iron catalyst that spurs alkene hydrosilylation reactions (Science, DOI: 10.1126/ science.1214451). Alkene hydrosilylation—in which a silicon hydride adds across a carbon-carbon double bond—is typically done with expensive metal catalysts based on platinum or rhodium, most of which is not recovered. By tinkering with the substituents of a bis(imino)pyridine iron dinitrogen catalyst they’d previously developed for olefin hydrogenations (Inorg. Chem., DOI: 10.1021/ic902162z), researchers led by Princeton University’s Paul J. Chirik were able to get tertiary silanes to add across terminal olefins in exclusively anti-Markovnikov fashion. That is, the silicon group WWW.CEN-ONLIN E .ORG
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magnesium, manganese, silicon carbide, silicon metal, yellow phosphorus, and zinc. U.S. Trade Representative Ron Kirk called the ruling “a tremendous victory” for U.S. manufacturers. “The Obama Administration will continue to ensure that China and every other country play by the rules so that U.S. workers and companies can compete and succeed on a level playing field,” Kirk said. China’s Ministry of Commerce said it “deeply regrets” the decision, but vowed to abide by the ruling. China had argued that it restricted exports to protect the environment and conserve exhaustible natural resources. “WTO should not only uphold free trade but also allow members to take necessary steps to protect the environment and natural resources,” the ministry said. Notably, the ruling does not apply to rare earths, a group of 17 elements critical to the production of an array of high-tech products, including solar panels and flat-screen TVs. China, which accounts for 95% of global rare-earth production, has limited output and set strict export quotas, causing global prices to climb sharply. EU Commissioner for Trade Karel De Gucht expressed hope that in light of WTO’s decision in the raw materials case, Beijing will now revise all of its export policies. “I expect China to bring its overall export regime—including for rare earths—in line with WTO rules,” De Gucht said.—GLENN HESS
adds only to the less substituted carbon at the end of the chain, producing the terminal alkyl silanes used in various commercial applications. The iron compounds can complete the reaction in as little as 15 minutes, and they don’t produce internal isomers that are unwanted by-products of the reaction with Pt or Rh catalysts. “We knew from our olefin hydrogenation work that these compounds were fast, but we were still amazed at their performance in hydrosilylation,” Chirik tells C&EN. “The results of Chirik’s fine-tuning have created an excellent catalyst for specific formation of a siliconterminated alkyl while utilizing quite low catalyst loading as well as tertiary silane,” comments Joyce Y. Corey, an expert on organosilicon chemistry at the University of Missouri, St. Louis. Corey also notes that the hydrosilylation reactions take place at room temperature and in the absence of solvent. “These features fit in well with the tenets of green chemistry,” she says. Chirik has teamed up with specialty chemical company Momentive, with the hope of using the iron catalysts to make products on an industrial scale. “Ideally, the sensitivity to moisture and oxygen of these catalysts needs to be improved to make them more practical for large-scale chemical processes,” says Keith J. Weller, Momentive’s group manager for engineered materials. “We firmly believe that these catalysts have the potential for use in the production of a wide range of organofunctional silanes and silicones.”—BETHANY HALFORD
FE BRUARY 6, 20 12
