LETTER
Catalytic Epoxidation of Terpenes
1097
Table 2 H2O2 Epoxidation of Terpenes and Inner Olefina
Supporting Information for this article is available online at
Entry
Alkene
Product
Yield (%)b
O
Acknowledgment
1
92
This work was partially supported by a Grant-in-Aid for Scientific
Research on Priority Areas ‘Advanced Molecular Transformation
of Carbon Resources’ from the Ministry of Education, Culture,
Sports, Science, and Technology, Japan. We are grateful to Prof.
Dr. Akira Sekiguchi in Department of Chemistry, Graduate School
of Pure and Applied Sciences, University of Tsukuba for the helpful
cooperation.
O
O
2
87
75
3c
4
93
5d
87e
References and Notes
(1) (a) Eggersdorfer, M. In Ullmann’s Encyclopedia of
Industrial Chemistry, 6th ed., Vol. 35; Wiley-VCH:
Weinheim, 2003, 653. (b) Corma, A.; Iborra, S.; Velty, A.
Chem. Rev. 2007, 107, 2411.
O
(2) Sienel, G.; Rieth, R. In Ullmann’s Encyclopedia of
Industrial Chemistry, 6th ed., Vol. 12; Wiley-VCH:
Weinheim, 2003, 279.
6
7
98
75
OH
OH
(3) (a) Trost, B. M. Science 1991, 254, 1471. (b) Sheldon,
R. A. Chem. Ind. 1992, 903.
(4) Strukul, G. In Catalytic Oxidations with Hydrogen Peroxide
as Oxidant; Kluwer Academic Publishers: The Netherlands,
1992.
O
O
(5) (a) Sato, K.; Aoki, M.; Takagi, J.; Noyori, R. J. Am. Chem.
Soc. 1997, 119, 12386. (b) Sato, K.; Aoki, M.; Noyori, R.
Science 1998, 281, 1646. (c) Sato, K.; Takagi, J.; Aoki, M.;
Noyori, R. Tetrahedron Lett. 1998, 39, 7549. (d) Sato, K.;
Aoki, M.; Takagi, J.; Zimmermann, K.; Noyori, R. Bull.
Chem. Soc. Jpn. 1999, 72, 2287. (e) Sato, K.; Hyodo, M.;
Takagi, J.; Aoki, M.; Noyori, R. Tetrahedron Lett. 2000, 41,
1439. (f) Sato, K.; Hyodo, M.; Aoki, M.; Zheng, X.-Q.;
Noyori, R. Tetrahedron 2001, 57, 2469. (g) Usui, Y.; Sato,
K. Green Chem. 2003, 5, 373. (h) Usui, Y.; Sato, K.;
Tanaka, M. Angew. Chem. Int. Ed. 2003, 42, 5623. (i) Kon,
Y.; Usui, Y.; Sato, K. Chem. Commun. 2007, 4399. (j)Kon,
Y.; Yazawa, H.; Usui, Y.; Sato, K. Chem. Asian J. 2008, 3,
1642. (k) Chishiro, T.; Kon, Y.; Sato, K. J. Synth. Org.
Chem. Jpn. 2008, 66, 1085.
(6) For recent examples, see: (a) Rüsch gen. Klaas, M.;
Warwel, S. Org. Lett. 1999, 1, 1025. (b) Villa, A. L.; Sels,
B. F.; De Vos, D. E.; Jacobs, P. A. J. Org. Chem. 1999, 64,
7267. (c) Salles, L.; Brégeault, J.-M.; Thouvenot, R. Surf.
Chem. Catal. 2000, 3, 183. (d) Skrobot, F. C.; Valente, A.
A.; Neves, G.; Rosa, I.; Rocha, J.; Cavaleiro, J. A. S. J. Mol.
Catal. A: Chem. 2003, 201, 211. (e) Woitiski, C. B.;
Kozlov, Y. N.; Mandelli, D.; Nizova, G. V.; Schuchardt, U.;
Shul’pin, G. B. J. Mol. Catal. A: Chem. 2004, 222, 103.
(f) Eimer, G. A.; Díaz, I.; Sastre, E.; Casuscelli, S. G.;
Crivello, M. E.; Herrero, E. R.; Perez-Pariente, J. Appl.
Catal., A 2008, 343, 77.
8
9
82
82
O
a Reaction conditions: alkene (3.0 mmol), 60% H2O2 (3.9 mmol),
Na2WO4 (0.24 mmol), [Me(n-C8H17)3N]HSO4 (0.24 mmol),
PhP(O)(OH)2 (0.12 mmol), NaOH (0.18 mmol), 25 °C, 1000 rpm, 12 h.
b Yield on the basis of alkene, determined by GC analysis with biphe-
nyl as internal standard.
c 30% H2O2 was used instead of 60% H2O2.
d The reaction was run using 100 g of 3-carene, 1.3 equiv of 60%
H2O2, 4 mol% of Na2WO4, 2 mol% of PhP(O)(OH)2, 4 mol% of
[Me(n-C8H17)3N]HSO4, 4 mol% of NaOH.
e Isolated yield after distillation.
In summary, we have developed a green and practical
method for terpene epoxidation using aqueous H2O2 as an
oxidant under organic solvent-free conditions. The cata-
lytic system, which consists of Na2WO4, PhP(O)(OH)2,
and [Me(n-C8H17)3N]HSO4, having high activity under
nearly neutral pH conditions at ambient temperature,
achieved the excellent yield and selectivity for epoxida-
tion of very challenging acid-sensitive terpenes. The ap-
plication of these conditions to the other challenging
products, for example, styrene oxide derivatives, is now
under investigation.
(7) For recent reviews, see: (a) Applied Homogeneous
Catalysis with Organometallic Compounds, 2nd ed.;
Cornils, B.; Herrmann, W. A., Eds.; Wiley-VCH:
Weinheim, 2002. (b) Lane, B. S.; Burgess, K. Chem. Rev.
2003, 103, 2457. (c) Modern Oxidation Methods; Bäckvall,
J.-E., Ed.; Wiley-VCH: Weinheim, 2004.
(8) Selective oxidation of monocyclic and noncyclic terpenes
using PCWP–H2O2 system in CHCl3 has been reported:
Sakaguchi, S.; Nishiyama, Y.; Ishii, Y. J. Org. Chem. 1996,
61, 5307.
Synlett 2009, No. 7, 1095–1098 © Thieme Stuttgart · New York