Organic Letters
Letter
(5) Simone, D. O.; Kennelly, T.; Brungard, N. L.; Farrauto, R. J. Appl.
Catal. 1991, 70, 87−100.
Table 2. Influence of Halide and Base on Hydration of 5
(6) Zhdanko, A.; Strobele, M.; Maier, M. E. Chem.Eur. J. 2012, 18,
̈
14732−14744.
(7) (a) Gaillard, S.; Bosson, J.; Ramon
́
, R. S.; Nun, P.; Slawin, A. M.
ez-
ez, A.; Oonishi, Y.; Meiries, S.; Nolan, S. P. Organometallics 2013,
Z.; Nolan, S. P. Chem.Eur. J. 2010, 16, 13729−13740. (b) Gom
Suar
32, 1106−1111.
́
́
entry
additive
time (h)
yield (%)
1
2
3
4
5
none
4
24
24
2
99
2
(8) Nevado, C.; Echavarren, A. M. Chem.Eur. J. 2005, 11, 3155−
Bu4N+OH− (1%)
3164.
Bu4N+Cl− (1%)
8
(9) Burfield, D. R.; Goh, E. H.; Ong, E. H.; Smithers, R. H. Gazz.
Chim. Ital. 1983, 113, 841−3.
Ga(OTf)3 (2%) added to entry 2
Ga(OTf)3 (2%) added to entry 3
99
99
2
(10) (a) Ghosh, N.; Nayak, S.; Sahoo, A. K. J. Org. Chem. 2010, 76,
500−511. (b) Wang, D.; Cai, R.; Sharma, S.; Jirak, J.; Thummanapelli,
S. K.; Akhmedov, N. G.; Zhang, H.; Liu, X.; Petersen, J. L.; Shi, X. J.
Am. Chem. Soc. 2012, 134, 9012−9019.
influence the later stage in the gold catalytic cycle (e.g.,
protodeauration), acting as co-catalysts to speed-up the
reactions.15
(11) (a) Bartolome,
Raducan, M.; Echavarren, A. M.; Espinet, P. Inorg. Chem. 2008, 47,
11391−11397. (b) Bartolome, C.; Ramiro, Z.; García-Cuadrado, D.;
Perez-Galan, P.; Raducan, M.; Bour, C.; Echavarren, A. M.; Espinet, P.
Organometallics 2010, 29, 951−956. (c) Nieto-Oberhuber, C.; Munoz,
́ ́ ́
C.; Ramiro, Z.; Perez-Galan, P.; Bour, C.;
In conclusion, high gold affinity impurities (halides, bases) in
solvents, starting materials, filtration, or drying agents could
affect the reactivity of gold catalysts adversely, which may
significantly reduce the TON of cationic gold-catalyzed
reactions. The use of a suitable acid activator (e.g., HOTf,
In(OTf)3) reactivates the gold catalyst and contributes to
making the reaction proceed smoothly at low gold catalyst
loading. A similar protocol could benefit other cationic metal
catalysis.
́
́
́
̃
M. P.; Bunuel, E.; Nevado, C.; Car
́
denas, D. J.; Echavarren, A. M.
Angew. Chem., Int. Ed. 2004, 43, 2402−2406.
(12) (a) Tomas-Mendivil, E.; Toullec, P. Y.; Díez, J.; Conejero, S.;
Michelet, V.; Cadierno, V. Org. Lett. 2012, 14, 2520−2523. (b) Toullec,
P. Y.; Genin, E.; Antoniotti, S.; Genet, J.-P.; Michelet, V. Synlett 2008,
2008, 707−711.
̃
́
̂
(13) (a) Hashmi, A. S. K.; Schwarz, L.; Choi, J.-H.; Frost, T. M.
Angew. Chem., Int. Ed. 2000, 39, 2285−2288. (b) Zhou, C.-Y.; Chan, P.
W. H.; Che, C.-M. Org. Lett. 2005, 8, 325−328.
(14) Tang, Y.; Yu, B. RSC Adv. 2012, 2, 12686−12689.
(15) Xi, Y.; Wang, D.; Ye, X.; Akhmedov, N. G.; Petersen, J. L.; Shi,
X. Org. Lett. 2013, 16, 306−309.
ASSOCIATED CONTENT
* Supporting Information
■
S
Experimental procedure. This material is available free of charge
AUTHOR INFORMATION
Corresponding Authors
■
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
We are grateful to the National Science Foundation for
financial support (CHE-1111316).
■
REFERENCES
■
(1) (a) Hardacre, C.; Katdare, S. P.; Milroy, D.; Nancarrow, P.;
Rooney, D. W.; Thompson, J. M. J. Catal. 2004, 227, 44−52.
(b) Mukherjee, A.; Sen, T. K.; Ghorai, P. K.; Mandal, S. K. Sci. Rep.
2013, 3. (c) Wang, Z. J.; Benitez, D.; Tkatchouk, E.; Goddard Iii, W.
A.; Toste, F. D. J. Am. Chem. Soc. 2010, 132, 13064−13071.
(2) (a) Wang, W.; Kumar, M.; Hammond, G. B.; Xu, B. Org. Lett.
2014, 16, 636−639. (b) Malhotra, D.; Mashuta, M. S.; Hammond, G.
B.; Xu, B. Angew. Chem., Int. Ed. 2014, 53, 4456−4459. (c) Kumar, M.;
Jasinski, J.; Hammond, G. B.; Xu, B. Chem.Eur. J. 2014, 20, 3113−
3119. (d) Kumar, M.; Scobie, M.; Mashuta, M. S.; Hammond, G. B.;
Xu, B. Org. Lett. 2013, 15, 724−727. (e) Wang, W.; Hammond, G. B.;
Xu, B. J. Am. Chem. Soc. 2012, 134, 5697−5705.
(3) (a) Hashmi, A. S. K.; Schuster, A. M.; Rominger, F. Angew. Chem.,
Int. Ed. 2009, 48, 8247−8249. (b) Hashmi, A. S. K.; Schuster, A. M.;
Gaillard, S.; Cavallo, L.; Poater, A.; Nolan, S. P. Organometallics 2011,
30, 6328−6337.
(4) (a) Oxford, S. M.; Henao, J. D.; Yang, J. H.; Kung, M. C.; Kung,
H. H. Appl. Catal., A 2008, 339, 180−186. (b) Chandler, B. D.;
Kendell, S.; Doan, H.; Korkosz, R.; Grabow, L. C.; Pursell, C. J. ACS
Catal. 2012, 2, 684−694. (c) Bartholomew, C. H. Appl. Catal., A 2001,
212, 17−60.
D
dx.doi.org/10.1021/ol501663f | Org. Lett. XXXX, XXX, XXX−XXX