Subscribe to RSS
Please copy the URL and add it into your RSS Feed Reader.
https://www.thieme-connect.de/rss/thieme/en/10.1055-s-00000083.xml
Synlett 2002(3): 0403-0406
DOI: 10.1055/s-2002-20451
DOI: 10.1055/s-2002-20451
LETTER
© Georg Thieme Verlag Stuttgart · New York
Asymmetric Construction of the Azaspiro[5.6]dodec-9-ene System in Marine Natural Toxins
Further Information
Received
29 December 2001
Publication Date:
05 February 2007 (online)
Publication History
Publication Date:
05 February 2007 (online)
![](https://www.thieme-connect.de/media/synlett/200203/lookinside/thumbnails/10.1055-s-2002-20451-1.jpg)
Abstract
The asymmetric formation of azaspiro[5.6]dodec-9-ene system is described. The Diels-Alder reactions of an α-methylene caprolactam and diene in the presence of a Cu(II) and (S,S)-tBu-BOX complex afford the desired spirocyclic compounds with good exo-selectivity as well as excellent enantioselectivity. These exo-adducts would be applicable to the synthesis of marine natural toxins including the corresponding cyclic imine moiety.
Key words
asymmetric synthesis - Diels-Alder reactions - lactams - natural products
-
1a
Uemura D.Chou T.Haino T.Nagatsu A.Fukuzawa S.Zeng S.-z.Chen H.-s. J. Am. Chem. Soc. 1995, 117: 1155 -
1b
Chou T.Kamo O.Uemura D. Tetrahedron Lett. 1996, 37: 4023 -
1c
Chou T.Haino T.Kuramoto M.Uemura D. Tetrahedron Lett. 1996, 37: 4027 -
1d
Takada N.Umemura N.Suenaga K.Chou T.Nagatsu A.Haino T.Yamada K.Uemura D. Tetrahedron Lett. 2001, 42: 3491 - 2
Takada N.Umemura N.Suenaga K.Uemura D. Tetrahedron Lett. 2001, 42: 3495 -
3a For total synthesis of pinnatoxin A:
McCauley JA.Nagasawa K.Lander PA.Mischke SG.Semones MA.Kishi Y. J. Am. Chem. Soc. 1998, 120: 7647 -
3b For other synthetic studies of pinnatoxins see:
Noda T.Ishiwata A.Uemura S.Sakamoto S.Hirama M. Synlett 1998, 298 -
3c
Suthers BD.Jacobs MF.Kitching W. Tetrahedron Lett. 1998, 39: 2621 -
3d
Ishiwata A.Sakamoto S.Noda T.Hirama M. Synlett 1999, 692 -
3e
Nitta A.Ishikawa A.Noda T.Hirama M. Synlett 1999, 695 -
4a
Sugimoto T.Ishihara J.Murai A. Tetrahedron Lett. 1997, 38: 7379 -
4b
Ishihara J.Sugimoto T.Murai A. Synlett 1998, 603 -
4c
Sugimoto T.Ishihara J.Murai A. Synlett 1999, 541 -
5a
Evans DA.Miller SJ.Lectka T. J. Am. Chem. Soc. 1993, 115: 6460 -
5b
Evans DA.Murry JA.von Matt P.Norcross RD.Miller SJ. Angew. Chem. Int. Ed. Engl. 1995, 34: 798 -
5c
Evans DA.Miller SJ.Lectka T.von Matt P. J. Am. Chem. Soc. 1999, 121: 7559 -
5d
Evans DA.Barnes DM.Johnson JS.Lectka T.von Matt P.Miller SJ.Murry JA.Norcross RD.Shaughnessy EA.Campos KR. J. Am. Chem. Soc. 1999, 121: 7582 -
5e Review:
Johnson JS.Evans DA. Acc. Chem. Res. 2000, 33: 325 - 6 Very recently, Romo reported the pericyclic reaction of a similar substrate, though it was racemic formation:
Yang J.Cohn ST.Romo D. Org. Lett. 2000, 2: 763 -
7a
Zezza CA.Smith MB.Ross BA.Arhin A.Cronin PLE. J. Org. Chem. 1984, 49: 4397 -
7b
Hua DH.Miao SW.Bharathi SN.Katsuhira T.Bravo AA. J. Org. Chem. 1990, 55: 3682 -
7c
Ahn Y.Cardenas GI.Yang J.Romo D. Org. Lett. 2001, 3: 751 -
8a
Danishefsky SJ.Kitahara T.McKee R.Schuda PF. J. Am. Chem. Soc. 1976, 98: 6715 -
8b
Wada M.Nishihara Y.Akiba K. Tetrahedron Lett. 1984, 25: 5405 - 9
Berson JA.Hamlet Z.Mueller WA. J. Am. Chem. Soc. 1962, 84: 297 -
10a
Roush WR.Brown BB. J. Org. Chem. 1992, 57: 3380 -
10b
Fotiadu F.Michel F.Buono G. Tetrahedron Lett. 1990, 31: 4863 -
10c
Takeda K.Imaoka I.Yoshii E. Tetrahedron 1994, 50: 10839 -
10d
Adam W.Albert R.Hasemann L.Salgado VON.Nestler B.Peters E.-M.Peters K.Prechtl F.von Schnering HG. J. Org. Chem. 1991, 56: 5782 - 11 The stereochemistry of the adducts was determined by the NOE enhancement of their derivatives, and its absolute configuration was determined by the Kusumi method (Scheme 4):
Nagai Y.Kusumi T. Tetrahedron Lett. 1995, 36: 1853 - 12 Interestingly, the (-)-siam·Cu(II) complex was not suitable for the Diels-Alder reaction of α-methylene caprolactam system. The reaction of 4 and 6 in the presence of (-)-siam·Cu(SbF6)2 at 24 °C for 72 h afforded 7 in 10% yield, along with the recovered lactam (66% yield), and the significant exo-selectivity was not observed (exo/endo = 55:45). For (-)-siam:
Owens TD.Hollander FG.Oliver AG.Ellman JA. J. Am. Chem. Soc. 2001, 123: 1539