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J. Li et al. / Catalysis Communications 12 (2011) 1401–1404
iodide [11,21]. Incidentally, in this alkyl nitrite reaction in the
presence of small amount of halogen anions, the Au (III) catalysts
without the co-presence such as CuCl2 hardly deactivated, whereas it
is a well-known additive in a Wacker-type reaction. Therefore, it is
supposed that the smooth redox cycle of the Au catalyst is mainly due
to the introduction of KI and alkyl nitrite, especially alkyl nitrite. In the
case of DEC synthesis, alkyl nitrite is one of the substrates to
synthesize DEC, but it is also an oxidant at the same time.
4. Conclusions
The results of experimental studies described in this paper
demonstrate high catalytic activity of a gold N-containing ligand
complex in the carbonylation of alkyl nitrite to dialkyl carbonate
with KI as the promoter. The highest activity was achieved using
[AuCl2(phen)]Cl/KI as the catalyst. Both the ligand and promoter play
crucial roles in increasing the catalytic activity of the gold ion in a
homogeneous reaction. It is the first report of applying gold N-
containing ligand complex as a homogeneous catalyst for carbonyl-
ation of alkyl nitrite.
Acknowledgments
The authors thank the Research Foundation of Science, Huazhong
University of Science and Technology for the financial support. We
also thank the Analytical and Testing Center, Huazhong University of
Science and Technology for the spectroscopic analysis of the catalysts.
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