Intramolecular Hetero-Diels-Alder Reaction of Vinylallenes and Imines: Synthesis of 9-Methyl-1,2,3,4,5,6,7,8-octahydroacridine

Abstract

The intramolecular hetero-Diels-Alder reaction of vinyl­allenes and imines has been carried out. Depending on the substit­uents on the allene and the length of the tether linking diene and heterodienophile, the reaction proceeds thermally or with Lewis acid activation. The transformation of one of the adducts into a 9-substituted octahydroacridine is reported.

Key words

vinyl allenes - intramolecular reaction - hetero-Diels-Alder reaction - imines - cycloaddition

References

• 2 Regas D. Afonso MM. Galindo A. Palenzuela JA. Tetrahedron Lett.  2000,  41:  6781 
• 3 Regas D. Afonso MM. Rodríguez ML. Palenzuela JA. J. Org. Chem.  2003,  68:  7845 
• 4 Roush WR. Intramolecular Diels-Alder Reactions, In Comprehensive Organic Synthesis   Vol. 5:  Trost BM. Fleming I. Paquette LA. Pergamon; Oxford: 1991.  p.513-550  
• 5a Trost BM. Lautens M. Hung M. Carmichael C. J. Am. Chem. Soc.  1984,  106:  7641 
• 5b Rigby J. Tetrahedron Lett.  1982,  23:  1863 
• 5c Rigby J. Wilson J. J. Am. Chem. Soc.  1984,  106:  8217 
• 5d Rigby J. Wilson J. Senanayake C. Tetrahedron Lett.  1986,  27:  3329 
• 5e Snider BB. Liu T. J. Org. Chem.  2000,  65:  8490 
• 6 Regas D. Ruiz JM. Afonso MM. Galindo A. Palenzuela JA. Tetrahedron Lett.  2003,  44:  8471 
• 7 Okamura WH. Curtin ML. Synlett  1990,  1 
• 9a Green T. Wuts PGM. Protective Groups in Organic Chemistry   Wiley; New York: 1991.  p.364-366  
• 9b Midland MM. Afonso MM. J. Am. Chem. Soc.  1989,  111:  4368 
• 10a Pilato ML. Catalano VJ. Bell TW. J. Org. Chem.  2001,  66:  1525 
• 10b Kamata K. Tominaga Y. Tori-i A. Thiemann T. Matake S. Hetereocycles  1998,  48:  1663 

1

The term semicyclic refers to a dienic or vinylallenic system in which only one of the double bonds is a part of a cycle.

8

All compounds described in this paper were prepared in racemic form.