LiBF₄-Catalyzed Imino-Diels-Alder Reaction: A Facile Synthesis of Pyrano- and Furoquinolines [1]

Abstract

Lithium tetrafluoroborate efficiently catalyzes the imino-Diels-Alder reaction of aldimines with 3,4-dihydro-2H-pyran (DHP) and 2,3-dihydrofuran to afford the corresponding pyrano- and furoquinolines in high yields with high diastereoselectivity.

lithium tetrafluoroborate - imino-Diels-Alder reaction - tetrahydroquinolines

References

1

IICT Communication No. 4727.

2a Weinreb SM. In Comprehensive Organic Synthesis   Vol. 5:  Trost BM. Fleming I. Pergamon; Oxford: 1991.  p.401-449  

2b Boger DL. Weinreb SM. Hetero Diels-Alder Methodology in Organic Synthesis   Academic Press; San Diego: 1987.  Chap. 2 and 9.

2c Tietze LF. Kettschau G. Top. Curr. Chem.  1997,  189:  1 

3a Yamada N. Kadowaki S. Takahashi K. Umezu K. Biochem. Pharmacol.  1992,  44:  1211 

3b Faber K. Stueckler H. Kappe T. Heterocyl. Chem.  1984,  21:  1177 

3c Johnson JV. Rauckman S. Baccanari PD. Roth B. J. Med. Chem.  1989,  32:  1942 

4a Mohammed EA. Chem. Pap.  1994,  48:  261 

5a Povarov LS. Russ. Chem. Rev.  1967,  36:  656 

5b Babu G. Perumal PT. Tetrahedron Lett.  1998,  39:  3225 

6a Cabral J. Laszlo P. Tetrahedron Lett.  1989,  30:  7237 

6b Crousse B. Begue JP. Delpon DB. Tetrahedron Lett.  1998,  39:  5765 

7a Worth DF. Perricone SC. Elsager EF. J. Heterocycl. Chem.  1970,  7:  1353 

7b Babu G. Perumal PT. Tetrahedron Lett.  1997,  38:  5025 

7c Ma Y. Qian C. Xie M. Sun J. J. Org. Chem.  1999,  64:  6462 

8a Hadden M. Stevenson PJ. Tetrahedron Lett.  1999,  40:  1215 

8b Makioka Y. Shindo T. Taniguchi Y. Takaki K. Fujwara Y. Synthesis  1995,  801 

9 Babu BS. Balasubramanian KK. Acros Organics Acta  2000,  7:  1