Hydrocyanation Minus The Cyanide - C&EN Global Enterprise (ACS

Article Options. PDF (131 KB) · Full Text HTML · Abstract · Figures · Steve Ritter. C&EN , 2016, 94 (8), pp 8–8February 22, 2016. Cite this:C&EN 201...
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NEWS OF THE WEEK

SPYING EYES IN THE SKY SECURITY: Legislation seeks to bar unauthorized drone flights over U.S. chemical facilities

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Chemical facilities fear that photosnapping drones could compromise trade secrets.

N RESPONSE to the soaring use of drones, Con-

SHUTTERSTOCK

gress has taken the first step toward prohibiting their unauthorized flight in the airspace over and near chemical plants and petroleum refineries. A bill (H.R. 4441) to reauthorize the Federal Aviation Administration (FAA) includes a provision that would direct the agency to set strict new guidelines to keep the unmanned aircraft away from critical infrastructure facilities. The House of Representatives’ Transportation & Infrastructure Committee approved the bill earlier this month. Rep. Brian Babin (R-Texas) says he offered the provision “as a way to protect our facilities and their employees from potentially hazardous and unauthorized drone activity.” Babin represents an area east of

HYDROCYANATION MINUS THE CYANIDE ORGANIC SYNTHESIS: Reversible

transfer reaction to make nitriles avoids toxic HCN

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YDROCYANATION is a go-to reaction for con-

verting an alkene to a nitrile, which is one of the most versatile functional groups available to chemists. The process is used industrially to produce adiponitrile, an intermediate for making nylon. However, it is rarely used in the lab or for fine chemicals production because the hydrogen cyanide required as a reagent is extremely toxic, volatile, and potentially explosive. Researchers in Germany have now designed an approach to hydrocyanation that not only avoids HCN’s pitfalls but is controllably reversible, which could make the reaction even more valuable (Science 2016, DOI: 10.1126/science.aae0427). Xianjie Fang, Peng Yu, and Bill Morandi of the Max

R5

R1 R2

R3 + R4 Alkene

R7 CN

R6 R8 Nitrile

R1

Transfer hydrocyanation Retrohydrocyanation • No hydrogen cyanide • Reversible control

R5 R3 + 6 CN R

R2 R4 Nitrile

CEN.ACS.ORG

R7 R8 Alkene

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Houston that is home to more petrochemical and refining facilities than any other congressional district. The American Chemistry Council (ACC), an industry trade group, says the legislation targets the “potential misuse of drones for illicit purposes without interfering with their growing use by the public for recreation and their use for commercial applications.” Perhaps the greatest threat is industrial espionage through aerial photography, says John J. Durkay, legal counsel for the International Safety Training Council, which trains contractors and employees at chemical and refining plants in southeastern Texas. “Sometimes enterprising individuals take it upon themselves to fly over a site and then see if they can sell the photos” to a competitor, Durkay tells C&EN. “Drones photographing units can compromise facility trade secrets.” Drones malfunctioning and crashing are another worry. “These facilities have a lot of power lines, communication towers, and so on,” Durkay says. “Especially problematic is that drones are getting quite a bit larger.” Because of their maneuverability, affordability, and capacity to carry items, terrorists could use small drones to attack industrial targets with explosives, ACC says. The bill now goes to the House floor for a vote. The Senate is expected to draft separate legislation to reauthorize FAA.—GLENN HESS, special to C&EN

Planck Institute for Coal Research use a nickel catalyst as a shuttle to pluck hydrogen and a cyano group from a donor nitrile and transfer them to an alkene to form a nitrile. The team shows the reaction is useful to make aryl nitriles and for functionalizing biomolecules such as tyrosine and estrone. In addition, the transfer hydrocyanation is made reversible on demand by selecting starting reagents that control the thermodynamic equilibrium of the reaction—the nitriles can be reverted to complementary alkenes. The team uses this retrohydrocyanation to make styrene, terpene, and aliphatic alkene derivatives from nitriles. The reversibility provides two main advantages, Morandi says. It guides selective formation of linear alkyl nitriles, in contrast to normal hydrocyanation where branched products are obtained. And in retrohydrocyanation mode, the nitrile group acts as a removable activating group for the construction of C–C bonds. “This practical and safe protocol for the HCN-free transfer hydrocyanation of alkenes is likely to fertilize nitrile chemistry,” notes organic chemist Hans-Günther Schmalz of the University of Cologne in a commentary accompanying the research paper. Schmalz envisions the approach stimulating new applications in academic and industrial labs, and perhaps in fine chemicals production. But he adds that the stoichiometric amounts of by-products formed could limit its use by companies already accustomed to safe handling of HCN.—STEVE RITTER

FEBRUARY 22, 2016