Subscribe to RSS
Please copy the URL and add it into your RSS Feed Reader.
https://www.thieme-connect.de/rss/thieme/en/10.1055-s-00000084.xml
Synthesis 2001(8): 1111-1113
DOI: 10.1055/s-2001-15053
DOI: 10.1055/s-2001-15053
SHORTPAPER
© Georg Thieme Verlag Stuttgart · New York
Photochemical Synthesis of Cyclopenta[c]-Anellated Benzopyrans and Benzothiopyrans
Further Information
Received
8 January 2001
Publication Date:
24 September 2004 (online)
Publication History
Publication Date:
24 September 2004 (online)
![](https://www.thieme-connect.de/media/synthesis/200108/lookinside/thumbnails/10.1055-s-2001-15053-1.jpg)
Abstract
On irradiation in the presence of 2,3-dimethylbut-2-ene the newly synthesized 2-oxo-2H-1-benzopyran- and 2-oxo-2H-1-benzothiopyran-4-carbonitriles are converted selectively to a cyclopenta[c]benzopyran or -thiobenzopyran, respectively. The reaction proceeds via addition of the alkene to the nitrile- and olefinic C-atoms of the triplet excited coumarin derivatives.
Key words
photochemistry - heterocycles - cycloadditions - nitriles - imines
- 1
Minto RE.Townsend CA. Chem. Rev. 1997, 97: 2537 - 2
Wolff S.Hoffmann HMR. Synthesis 1988, 760 - 3
Castellano AJ.Rapoport H. J. Org. Chem. 1986, 51: 1006 - 4
Büchi G.Weinreb SM. J. Am. Chem. Soc. 1971, 93: 746 - 5
Schwebel D.Ziegenbalg J.Kopf J.Margaretha P. Helv. Chim. Acta 1999, 82: 177 - 6
Mowry DT.Morner RR. J. Am. Chem. Soc. 1947, 69: 1831 - 7
Grissom JW.Klingberg D.Meyenburg S.Stallman BL. J. Org. Chem. 1994, 59: 7876 - 8
Agosta WC.Margaretha P. Acc. Chem.Res. 1996, 29: 179 -
9a
Andresen S.Margaretha P. J. Chin. Chem. Soc. 1995, 42: 991 - 10
Saito I.Shinozomo K.Matsuura T. Tetrahedron Lett. 1982, 23: 5439 - 11
Ito K.Nakajima K. J. Heterocycl. Chem. 1988, 25: 511