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Synlett 2002(3): 0403-0406
DOI: 10.1055/s-2002-20451
DOI: 10.1055/s-2002-20451
LETTER
© Georg Thieme Verlag Stuttgart · New YorkAsymmetric 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)

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
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