Table 3 Reduction of enediones
Notes and references
1 A. Ichihara, K. Shiraishi, H. Sato, S. Sakamura, K. Nishiyama,
R. Sakai, A. Furusaki and T. Matsumoto, J. Am. Chem. Soc., 1979, 99,
636.
2 H. Minato, Tetrahedron Lett., 1961, 2, 280.
3 For general reviews, see: V. Singh, S. R. Iyer and S. Pal, Tetrahedron,
2005, 61, 9197; P. Jankowski, S. Marczak and J. Wicha, Tetrahedron,
1998, 54, 12071.
4 P. Wasnaire, M. Wiaux, R. Touillaux and I. E. Marko´, Tetrahedron
Lett., 2006, 47, 985.
5 K. Morita, Z. Suzuki and H. Hirose, Bull. Chem. Soc. Jpn., 1968, 41,
2815; A. B. Baylis and M. E. D. Hillman, German Patent 2155113, 1972.
For a general review, see: D. Basavaiah, A. J. Rao and
Entry
Substrate
Product
Yielda (%)
T. Satyanarayana, Chem. Rev., 2003, 103, 811. For selected examples,
see reference 4 and those cited therein.
6 For some leading references, see: Q. Liu and T. Rovis, Org. Process Res.
Dev., 2007, 11, 598; W. Schrader, P. P. Handayani, C. Burstein and
F. Glorius, Chem. Commun., 2007, 716; T. E. Reynolds, C. A. Stern and
K. A. Scheidt, Org. Lett., 2007, 9, 2581; O. L. Epstein and T. Rovis,
Tetrahedron, 2006, 62, 11477; J. R. de Alaniz and T. Rovis, J. Am.
Chem. Soc., 2005, 127, 6284; M. Christmann, Angew. Chem., Int. Ed.,
2005, 44, 2632; A. E. Mattson, A. R. Bharadwaj and K. A. Scheidt,
J. Am. Chem. Soc., 2004, 126, 2314; D. Enders and T. Balensiefer, Acc.
Chem. Res., 2004, 37, 534; D. Enders and O. Niemeier, Synlett, 2004,
2111. For early references, see: H. Stetter and M. Schreckenberg, Angew.
Chem., Int. Ed. Engl., 1973, 12, 81; H. Stetter, Angew. Chem., Int. Ed.
Engl., 1976, 15, 639. For general reviews, see: H. Stetter and
H. Kuhlmann, Org. React., 1991, 40, 407.
1
85
2
97
7 Y. M. A. Yamada and S. Ikegami, Tetrahedron Lett., 2000, 41, 2165.
8 A. Itoh, S. Ozawa, K. Oshima and H. Nozaki, Bull. Chem. Soc. Jpn.,
1981, 54, 274; W. Pei, H. Wei and G. Li, Chem. Commun., 2002, 2412.
9 K. Ishihara, M. Kubota, H. Kurihara and H. Yamamoto, J. Org.
Chem., 1996, 61, 4560.
3
86
10 T. Veysoglu, L. A. Mitscher and J. K. Swayze, Synthesis, 1980, 807.
11 D. Seebach, Angew. Chem., Int. Ed. Engl., 1979, 18, 239.
12 For general reviews, see: M. Christmann, Angew. Chem., Int. Ed., 2005,
44, 2632; D. Enders and T. Balensiefer, Acc. Chem. Res., 2004, 37, 534;
J. S. Johnson, Angew. Chem., Int. Ed., 2004, 44, 2632. For selected
recent examples, see: J. L. Moore, M. S. Kerr and T. Rovis,
Tetrahedron, 2006, 62, 11478 and references cited therein; Z. Zhou,
F. Ji, M. Cao and G. Yang, Adv. Synth. Catal., 2006, 348, 1826;
T. Nakamura, O. Hara, T. Tamura, K. Makino and Y. Hamada,
Synlett, 2005, 155; D. Enders, K. Breuer and J. H. Teles, Helv. Chim.
Acta, 1996, 79, 1899.
13 For applications to total synthesis, see: P. E. Harrington and M. A. Tius,
J. Am. Chem. Soc., 2001, 123, 8509; B. M. Trost, C. D. Shuey,
F. DiNinno and S. S. McElvain, J. Am. Chem. Soc., 1979, 101, 1284.
14 For 11a, increasing the reaction time resulted in decreased yield.
15 See for examples: B. A. Pearlman, A. G. Padilla, J. T. Hach, J. L. Havens
and M. D. Pillai, Org. Lett., 2006, 8, 2111; S. El Sheikh, N. Kausch,
J. Lex, J.-M. Neudoerfl and H.-G. Schmaltz, Synlett, 2006, 1527;
H. Asahara, E. Mochizuki and T. Oschima, Tetrahedron Lett., 2006, 47,
7881; K. Yamamoto, M. F. Hentemann, J. G. Allen and
S. J. Danishefsky, Chem.–Eur. J., 2003, 9, 3242; J. Yu and E. J. Corey,
J. Am. Chem. Soc., 2003, 125, 3232 and references cited therein; C. Liu
and D. J. Burnell, J. Org. Chem., 1997, 62, 3683; W. Kroutil,
M. E. Lasterra-Sa´nchez, S. J. Maddrell, P. Mayon, P. Morgan,
S. M. Roberts, S. R. Thornton, C. J. Todd and M. Tu¨ter, J. Chem. Soc.,
Perkin Trans. 1, 1996, 2837.
a
Yields refer to pure, isolated products.
In summary, we have developed a short and connective
synthesis of bicyclic enediones. This new methodology involves
two key steps: a Morita–Baylis–Hillman coupling and an
intramolecular Stetter reaction. Various bicyclic structures can be
readily assembled via this versatile protocol. Moreover, the
Stetter reaction has been shown to be a powerful synthetic
tool that led, not only to 6-endo, but also to 7-endo-trig
cyclisations. Current efforts are now aimed at delineating the full
scope of this methodology, examining the reactivity of enediones
and using these substrates in the total synthesis of relevant natural
products. The results of these investigations will be reported in due
course.
Financial support for this work by the Universite´ catholique de
Louvain, the Fonds pour la Recherche dans l’Industrie et
l’Agriculture (FRIA, studentships to P.W.) and Merck Sharp
and Dohme (Merck Academic Development Award to I.E.M.) is
gratefully acknowledged.
16 L. C. Blaszczak and J. E. McMurry, J. Org. Chem., 1974, 39, 258.
17 A 24 h reaction time is necessary to complete the conversion of 11a into
the desired diketone 16a due to the formation of a transient and
unexpected 5-hydroxyenone intermediate.
This journal is ß The Royal Society of Chemistry 2007
Chem. Commun., 2007, 4755–4757 | 4757