- WILMINGTON, Del. (UPI) --
After years of research, scientists in Delaware have discovered a new way
of making key building blocks for many modern medicines, a breakthrough
over century-old techniques that inadvertently generate acids and other
toxic waste.
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- "The only byproduct of our reaction is water,"
researcher Mas Subramanian, a materials scientist at DuPont Central Research
and Development, told United Press International.
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- This simple, clean technique is not only environmentally
friendly, but also promises to drive down costs, the researchers said.
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- "This is a real advance, and I think it has a very
significant future," comment chemist William Dobier of the University
of Florida in Gainesville.
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- The technique uses fluorine, the element best known for
fighting cavities that also plays a pivotal role in modern medicine. Some
30 percent to 50 percent of all pharmaceuticals now contain fluorine, Dobier
told UPI, because it helps boost their effectiveness.
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- Scientists developed ways to insert fluorine into organic
chemicals a century ago, and with a few modifications these widely used
methods remain in use in industry today. However, "These processes
often involve many steps that generate large amounts of waste at each step,"
Subramanian explained, including hydrochloric acid. Cleaning up this waste
can prove quite expensive.
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- Subramanian and his colleague Leo Manzer discovered a
greener alternative that adds fluorine to the common organic compound benzene
in only one step. "I didn't expect this to work so well," Subramanian
said. Scientists for years have looked for organic methods to add fluorine
to chemicals. After three years of tinkering, Subramanian and Manzer found
an inorganic chemical to carry out the job instead. The compound in question
is called copper fluoride and is quite cheap, Subramanian said.
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- The technique removed hydrogen from benzene and replaces
it with fluorine. The freed hydrogen then combines with easily available
oxygen to become water. After tinkering with a variety of chemicals for
three years, the researchers found copper fluoride carried out the task
with extreme efficiency.
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- So far, the new technique has created organic compounds
known as fluorinated aromatics, often used in making drugs and farm-used
fungicides. Dobier, who is continuing work on Subramanian and Manzer's
findings with the help of two donated patents from DuPont, said it is likely
that similar techniques can make a wider range of fluorinated organic chemicals
in the future.
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- "Of course we have to optimize this for an industrial
route," Subramanian said. "This is only a laboratory demonstration.
But we can probably try doing this in six months to one year."
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- The scientists describe their findings in the September
6 issue of the journal Science.
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