Asymmetric Construction of the Azaspiro[5.6]dodec-9-ene System in Marine Natural Toxins

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.

asymmetric synthesis - Diels-Alder reactions - lactams - natural products

References

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