N. A. Kulkarni, K. Chen / Tetrahedron Letters 47 (2006) 611–613
613
Me
Me
University which is gratefully acknowledged. Our
gratitude is expressed to the Academic Paper Editing
Clinic, NTNU.
Me
Me
O
O
O
NOBn
H
N
N
O
S
H
N
S
NOBn
References and notes
Sn OTf
O
O
Sn OTf
OTf
SnBu3
OTf
Tol
O
1. For a recent review, see: Denmark, S. E.; Fu, J. Chem. Rev.
2003, 103, 2763, and references cited therein.
SnBu3
2. (a) Jain, R. P.; Williams, R. M. J. Org. Chem. 2002, 67,
6361; (b) Fabio, R. D.; Alvaro, G.; Bertani, B.; Donati, D.;
Giacobbe, S.; Marchioro, C.; Palma, C.; Lynn, S. M. J.
Org. Chem. 2002, 67, 7319.
Me
Me
Me
Me
NOBn
H
3. For recent reviews, see: (a) Puentes, C. O.; Kouznetsov, V.
J. Heterocycl. Chem. 2002, 39, 595; (b) Denmark, S. E.;
Almstead, N. G. In Modern Carbonyl Chemistry; Otera, J.,
Ed.; Wiley-VHC: Weinheim, 2000, Chapter 10 and refer-
ences cited therein; For some examples, see: (c) Shimizu,
M.; Kimura, M.; Watanabe, T.; Tamaru, Y. Org. Lett.
2005, 7, 637; (d) Solin, N.; Wallner, O. A.; Szabo, K. J. Org.
Lett. 2005, 7, 689; (e) Fernandes, R. A.; Yamamoto, Y. J.
Org. Chem. 2004, 69, 735; (f) Chen, Y.; Yekta, S.; Yudin, A.
K. Chem. Rev. 2003, 103, 3155; (g) Fernandes, R. A.;
Stimac, A.; Yamamoto, Y. J. Am. Chem. Soc. 2003, 125,
14133; (h) Kobayashi, S.; Ishitani, H. Chem. Rev. 1999, 99,
1069; (i) Hanessian, S.; Lu, P.-P.; Sanceau, J. Y.; Chemla,
P.; Gohda, K.; Fonne-Pfister, R.; Prade, L.; Cowan-Jacob,
S. W. Angew. Chem., Int. Ed. 1999, 38, 3160.
4. (a) Cook, G. R.; Maity, B. C.; Kargbo, R. Org. Lett. 2004,
6, 1741; (b) Berger, R.; Rabbat, P. M.; Leighton, J. L. J.
Am. Chem. Soc. 2003, 125, 9596; (c) Kobayashi, S.; Ogawa,
C.; Konishi, H.; Sugiura, M. J. Am. Chem. Soc. 2003, 125,
6610; (d) Hamada, T.; Manabe, K.; Kobayashi, S. Angew.
Chem., Int. Ed. 2003, 42, 3927.
5. (a) Miyabe, H.; Yamaoka, Y.; Naito, T.; Takemoto, Y. J.
Org. Chem. 2004, 69, 1415; (b) Miyabe, H.; Yamaoka, Y.;
Naito, T.; Takemoto, Y. J. Org. Chem. 2003, 68, 6745; (c)
Miyabe, H.; Nishimura, A.; Ueda, M.; Naito, T. Chem.
Commun. 2002, 14, 1454.
N
N
H
NOBn
N
N
O
O
O
O
Sn OTf
OTf
Ph
Ph
SnBu3
Figure 1. Proposed mechanism of the asymmetric allylatin.
(Xc = A and C), the Sn atom coordinates with the two
sulfonyl oxygen atoms. On the other hand, for 1
(Xc = B), the Lewis acid coordinates to the carbonyl
and a-oxime ether groups to form a transition state
species with a five-membered ring. The allyl group then
attacks from the si face to afford the desired product.
In summary, three camphor derived glyoxylic oxime
ethers were prepared and subjected to the allylation con-
dition using allyltributyltin to give the homoallylic
amines in high chemical yields and excellent stereoselec-
tivities in the presence of Sn(OTf)2. Further synthetic
applications of camphor derived glyoxylic oxime ethers
are under progress.
6. (a) Pan, J.-F.; Venkatesham, U.; Chen, K. Tetrahedron
Lett. 2004, 45, 9345; (b) Wang, S.-G.; Tsai, H. R.; Chen,
K. Tetrahedron Lett. 2004, 45, 6183; (c) Pan, J.-F.; Chen, K.
Tetrahedron Lett. 2004, 45, 2541; (d) Yang, K.-S.; Chen, K.
Org. Lett. 2000, 2, 729; (e) Chu, Y.-Y.; Yu, C.-S.; Chen,
C.-J.; Yang, K.-S.; Lain, J.-C.; Lin, C.-H.; Chen, K. J. Org.
Chem. 1999, 63, 6993.
7. Chen, J.-H.; Venkatesham, U.; Lee, L.-C.; Chen, K.
Tetrahedron, 2005, in press.
8. Niwa, Y.; Shimizu, M. J. Am. Chem. Soc. 2003, 125, 3720.
Acknowledgements
We thank the National Science Council of the Republic
of China (NSC 94-2113-M-003-003) and the National
Taiwan Normal University (ORD 93-C), for financial
support of this work. The X-ray crystal data were
collected and processed by National Taiwan Normal