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through this mild and convenient Au–CO/D2O-based catalytic
procedure.16 These preliminary results clearly demonstrate that
this Au–CO/D2O protocol is amenable to deuterium-labeled
compound synthesis, and work on this topic is ongoing.
In summary, we have developed a new, practical and efficient
gold-catalyzed method for highly selective semireduction of a range of
alkynes to the corresponding alkenes with CO/H2O as a reducing
agent. An essential feature of the present methodology is the exclusive
alkene selectivity independent of alkyne conversion. Furthermore, the
CO/D2O couple can work as a deuterium transfer reagent in the
presence of a gold catalyst, opening up a new avenue for cheap,
convenient, and green synthesis of deuterium-labeled alkenes.
This work was supported by the National Natural Science
Foundation of China (21073042, 21273044), the State Key Basic
Research Program of PRC (2009CB623506), the Research Fund
for the Doctoral Program of Higher Education (2012007000011)
and Science & Technology Commission of Shanghai Municipality
(08DZ2270500, 12ZR1401500).
Fig. 1 Syntheses of 1,2-dideuterioalkenes via CO/D2O-mediated alkyne
semireduction. The yield was determined by GC and deuteration efficiency
was confirmed by 1H NMR.
Notes and references
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and 12). Moreover, this reduction system was also applicable to
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Given that CO-mediated H2O activation is a central step in the
formation of the key Au-hydride species, we presumed that D2O as the
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during the semireduction process.
5628 | Chem. Commun., 2014, 50, 5626--5628
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