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520
Synlett
A. K. Das et al.
Letter
In summary, we have demonstrated the hydration of
terminal alkynes using a AuCl/MeOH catalyst system. This
methodology is both atom-economical and operationally
easier than those reported earlier and works without any
additive, ligand, or acid promoter. The catalytic system
showed good to excellent activity toward substituted phe-
nylacetylene and excellent functional-group tolerance;
however, it failed to hydrate internal alkynes. We proposed
that [MeO–Au] is an active catalyst, and the reaction pro-
ceeds through the enol ether intermediate pathway.
(5) (a) Khan, M. M. T.; Halligudi, S. B.; Shukla, S. J. Mol. Catal. 1990,
58, 299. (b) James, B. R.; Rempel, G. L. J. Am. Chem. Soc. 1969, 91,
863.
(
(
6) Blum, J.; Huminer, H.; Alper, H. J. Mol. Catal. 1992, 75, 153.
7) (a) Kadota, I.; Lutete, L. M.; Shibuya, A.; Yamamoto, Y. Tetrahe-
dron Lett. 2001, 42, 6207. (b) Kataoka, Y.; Matsumoto, O.;
Ohashi, M.; Yamagata, T.; Tani, K. Chem. Lett. 1994, 1283.
(8) Meier, I. K.; Marsella, J. A. J. Mol. Catal. 1993, 78, 31.
(9) Hiscox, W.; Jennings, P. W. Organometallics 1990, 9, 1997.
10) (a) Xu, X.; Kim, S. H.; Zhang, X.; Das, A. K.; Hirao, H.; Hong, S. H.
Organometallics 2013, 32, 164. (b) Wang, W.; Hammond, G. B.;
Xu, B. J. Am. Chem. Soc. 2012, 134, 5697. (c) Marion, N.; Ramon,
R. S.; Nolan, S. P. J. Am. Chem. Soc. 2009, 131, 448. (d) Leyva, A.;
Corma, A. J. Org. Chem. 2009, 74, 2067. (e) Mizushima, E.; Sato,
K.; Hayashi, T.; Tanaka, M. Angew. Chem. Int. Ed. 2002, 41, 4563.
(
Acknowledgment
(
1
f) Teles, J. H.; Brode, S.; Chabanas, M. Angew. Chem. Int. Ed.
998, 37, 1415.
This research was supported by the National Research Foundation of
Korea (NRF-2014R1A2A1A11050028; NRF-2014S1A2A2028156) and
the Institute for Basic Science (IBS-R006-D1), funded by the Korean
Government.
(
11) (a) Casado, R.; Contel, M.; Laguna, M.; Romero, P.; Sanz, S. J. Am.
Chem. Soc. 2003, 125, 11925. (b) de Frémont, P.; Singh, R.;
Stevens, E. D.; Petersen, J. L.; Nolan, S. P. Organometallics 2007,
26, 1376.
Supporting Information
(12) General Procedure for Alkyne Hydration
In a 4 mL reaction vial equipped with a magnetic stirring bar,
AuCl (5.8 mg, 0.025 mmol, 5 mol%) was added to MeOH (1 mL)
under argon atmosphere. The reaction mixture was stirred for 5
min, and then starting material (0.5 mmol, 1.0 equiv) and inter-
nal standard dodecane (1.0 equiv) were added, followed by
Supporting information for this article is available online at
http://dx.doi.org/10.1055/s-0035-1560573.
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References and Notes
defined amount of distilled H O (4.0 equiv). The resulting reac-
2
tion mixture was heated for 3 h, or for 24 h when needed, at
(
1) (a) Hintermann, L.; Labonne, A. Synthesis 2007, 1121.
65 °C. After completion of the reaction, the reaction mixture
(
(
b) Fukuda, Y.; Utimoto, K. J. Org. Chem. 1991, 56, 3729.
c) Kucherov, M. Ber. Dtsch. Chem. Ges. 1881, 14, 1540.
was diluted and filtered using CH Cl and injected in GC for
2
2
analysis.
(
2) (a) Tsuchimoto, T.; Joya, T.; Shirakawa, E.; Kawakami, Y. Synlett
000, 1777. (b) Kozhevnikov, I. V. Chem. Rev. 1998, 98, 171.
3) (a) Wasacz, J. P.; Badding, V. G. J. Chem. Educ. 1982, 59, 694.
b) Uemura, S.; Miyoshi, H.; Okano, M. J. Chem. Soc., Perkin
Trans. 1 1980, 1098. (c) Stork, G.; Borch, R. J. Am. Chem. Soc.
(
(
(
13) Lein, M.; Rudolph, M.; Hashmi, A. S. K.; Schwerdtfeger, P.
2
Organometallics 2010, 29, 2206.
14) A reviewer suggested that it could be MeOH –AuCl complex, a
(
+
(
Lewis acid assisted Brønsted acid system.
15) (a) Zhdanko, A.; Maier, M. E. Chem. Eur. J. 2014, 20, 1918.
1
1
964, 86, 935. (d) Budde, W. L.; Dessy, R. E. J. Am. Chem. Soc.
963, 85, 3964.
(
3
b) Mazzone, G.; Russo, N.; Sicilia, E. Organometallics 2012, 31,
074. (c) Krauter, C. M.; Hashmi, A. S. K.; Pernpointner, M.
ChemCatChem 2010, 2, 1226.
(4) Bruneau, C.; Dixneuf, P. H. Chem. Commun. 1997, 507.
©
Georg Thieme Verlag Stuttgart · New York — Synlett 2015, 26, 2517–2520