A Stable Germanone At Last - C&EN Global Enterprise (ACS

Mar 26, 2012 - After chemists tried for more than 100 years, a team has finally synthesized a stable heavy-element version of a ketone—a germanone...
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NEWS OF THE W EEK

A STABLE GERMANONE AT LAST MAIN-GROUP CHEMISTRY:

Japanese researchers isolate the first heavy ketone homolog

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FTER CHEMISTS tried for more than 100 years,

a team has finally synthesized a stable heavyelement version of a ketone—a germanone. Main-group inorganic chemists are celebrating the fundamental achievement because it’s the first time they have made an isolable molecule from a group-14 element below carbon on the periodic table that emulates the carbonyl moiety found in ketones and other important compounds such as aldehydes, esters, and amides. Researchers led by Tsukasa Matsuo and Kohei Tamao of Japan’s RIKEN Advanced Science Institute pulled off the feat by surrounding a Ge=O bond with a pair of bulky substituents (Nat. Chem., DOI: 10.1038/nchem.1305). Previous attempts to make carbonyl homologs incorporating silicon, germanium, tin, or lead failed because their highly polarized double bonds to oxygen were too reactive. But over the past decade, inorganic chemists have learned how to use large hydrocar-

COMMUNICATING HAZARDS REGULATION: OSHA adopts global system for chemical safety information

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EW WARNING LABELS and standardized de-

scriptions of chemicals’ hazards are coming to U.S. labs, factory floors, and other workplaces. Through a regulation released last week, the Occupational Safety & Health Administration is bringing U.S. requirements for communicating chemical safety information to workers in line with an international system. Labor Secretary Hilda L. Solis says OSHA’s revised hazard communication standard “will improve the quality, consistency, and clarity of hazard information that workers receive, making it safer for workers to do their jobs and easier for employers to stay competitive in the global marketplace.” She adds, “Exposure to hazardous chemicals is one of the most serious dangers facing American workers today.” The agency’s move will require chemical makers and importers to use warning symbols that were developed through the United Nations. Called pictograms, the symbols are designed to communicate chemical hazard information to workers regardless

bon substituents to stabilize an array of single- and multiple-bonded heavy-element carbon analogs containing group-13 to group-16 elements. The germanone’s fused-ring substituents with pendant ethyl groups act like a barbed-wire fence to shield the Ge=O bond and inhibit reactivity. The RIKEN researchers found that the Ge=O bond in the germanone is still highly polarized. And although it’s technically a double bond, the bond order is only 1.25. As a result, the germanone displays reactivity not typical of ordinary ketones. For example, the researchers found that it reacts with water to form a diol and with carbon dioxide to form a cyclic carbonate. “This synthesis is an important development in the field of multiple bonding involving heavier main-group elements, nicely demonstrating the power of the kinetic stabilization of otherwise highly reactive species,” comments silicon chemist Akira Sekiguchi of the University of Tsukuba, in Japan. Main-group chemist Philip P. Power of the University of California, Davis, writing in a Nature Chemistry commentary, calls the germanone synthesis “a highly notable event.” Power adds that the door is now open for “what will undoubtedly be a very rich chemistry.”— STEVE RITTER

of whether they can read or the language they use. Companies will also have to incorporate standardized language in the material safety data sheets they provide to customers about products’ hazards. Currently, each producer may choose the wording for its safety data sheets. In some cases, the description of a substance’s hazard varies substantially among safety data sheets from different suppliers, says Michael J. Wright, health, safety, and environment director for the United Steelworkers, which represents chemical and refinery workers. The Steelworkers and the American Chemistry Council, a chemical manufacturers’ organization, back U.S. adoption of the international scheme, called the Globally Harmonized System of Classification & Labelling of Chemicals. Michael P. Walls, ACC vice president of regulatory and technical affairs, says OSHA’s new standard “will help our industry improve the communication of important safety information, minimize transaction costs, and create efficiencies in labeling chemicals both domestically and abroad. It will also help promote better trade relations by minimizing differences between countries.” Plus, he says, it could improve U.S. exports. Governments, businesses, and labor groups worked through the UN to develop the Globally Harmonized System with the aim of protecting human health and facilitating trade. Thus far, 67 countries have adopted at least part of it.—CHERYL HOGUE

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The first stable heavy ketone, a germanone.

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