References
- Gewald , K. , Bellmann , P. and Jänsch , H-J. 1980 . Liebigs Ann. Chem. , : 1623
- Camparini , A. , Ponticelli , F. and Tedeschi , P. 1982 . J. Chem. Soc., Perkin Trans 1 , : 2391
- Tagawa , Y. and Goto , Y. 1987 . Heterocycles , 26 : 2921
- Drummond , J. , Johnson , G. , Nickell , D. G. , Ortwine , D. F. , Bruns , R. F. and Welbaum , B. 1989 . J. Med. Chem. , 32 : 2116
- Unsuccessful results were obtained both with piperidine and neutral or basic Al2O3 under different conditions
- Katritzky , A. L. , Long , Q-H. , Lue , P. and Jozwiak , A. 1990 . Tetrahedron , 46 : 8153
- Stork , G. , Brizzolara , A. , Landesman , H. , Szmuszkovicz , J. and Terrel , R. 1963 . J. Am. Chem. Soc. , 85 : 207