Re: HOLEY Fullerenes, Batman!

From: Brett Paatsch (paatschb@optusnet.com.au)
Date: Tue Jun 17 2003 - 06:27:08 MDT

  • Next message: Spudboy100@aol.com: "Re: HOLEY Fullerenes, Batman!"

    What would be neat would be if we could find some natty way of getting
    nanoparticles containing cytotoxins directed in on monoclonal quantum dot
    labelled tumor sites. It would give us a nice way of doing cell specific
    chemotherapy with less side effects.

    Brett Paatsch

    ---
    Spudboy writes:
    > http://pubs.acs.org/cen/topstory/8124/8124notw1.html
    >
    > HOLEY FULLERENE OPENS WIDE FOR H2
    > Open-cage derivative is first to provide H2-encapsulated complex in 100%
    yield
    > RON DAGANI
    >
    > Japanese chemists for the first time have prepared an open-cage fullerene
    derivative with an orifice large enough to allow a hydrogen molecule to be
    inserted into the cage in 100% yield [J. Am. Chem. Soc., 125, 7152 (2003)].
    >
    > "I think it is an important advance for this field, since I can see this
    type of system being used for H2 storage once C60 becomes cheaper," comments
    Yves Rubin, a chemistry professor at the University of California, Los
    Angeles.
    >
    > Scientists are looking for efficient methods for stuffing fullerene cages
    with metal atoms or gases to make new types of functional materials.
    >
    > Two years ago, Rubin and his collaborators at UCLA and Yale University
    reported the synthesis of a fullerene derivative featuring a "mouth" large
    enough to accept and trap a H2 molecule in 5% yield (C&EN, April 23, 2001,
    page 11). Although the yield has since been improved to 10%, this system
    still cannot compete with the new Japanese molecule, which Rubin says is
    better because it has a slightly larger orifice.
    >
    > The new molecule was prepared from C60 in three steps in 40% overall yield
    by chemistry professor Koichi Komatsu and coworkers Yasujiro Murata and
    Michihisa Murata at Kyoto University. When they expose the compound to
    hydrogen gas at 800 atm and 200 °C in an autoclave, 100% encapsulation is
    achieved within eight hours, they report.
    >
    > None of the encapsulated hydrogen escaped when a solution of the
    endohedral complex was monitored for more than three months at room
    temperature. However, hydrogen was released slowly when the solution was
    heated above 160 °C, Komatsu says.
    >
    > During mass spectral studies, the Kyoto group discovered that laser
    irradiation can cause the endohedral complex to regenerate pristine
    buckminsterfullerene with H2 inside--that is, H2@C60--in the gas phase. This
    suggests that endohedral fullerene complexes might one day be prepared
    entirely by organic synthesis, Komatsu tells C&EN. In fact, his group is now
    aiming to close the orifice chemically to achieve a chemical synthesis of
    H2@C60.
    >
    >
    >
    


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