Publication Type |
Journal Article |
Title |
Flavone-Nitrogen Heterocycle Conjugate Formation by 1,3-Dipolar Cycloadditions |
Authors |
Regina M. S. Sousa Diana C. G. A. Pinto Artur M. S. Silva Vanda Vaz Serra Ana I. R. N. A. Barros Maria A. F. Faustino M. Graca P. M. S. Neves Jose A. S. Cavaleiro |
Groups |
|
Journal |
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY |
Year |
2012 |
Month |
January |
Volume |
|
Number |
1 |
Pages |
132-143 |
Abstract |
Azomethine ylides generated in situ from the reaction of N-[2-,3- and 4-(chromon-2-yl)phenyl] glycine and paraformaldehyde can be trapped with dipolarophiles in 1,3-dipolar cycloaddition reactions to yield flavone-nitrogen heterocycle dyads. These azomethine ylides proved to be reactive with electron-poor dipolarophiles, affording the expected adducts. The use of microwave irradiation as an alternative source of heating has significant advantages and allows a reduction of both reaction time and temperature. The use of benzaldehydes as dipolarophiles afforded flavone-oxazolidine dyads, and the results indicate that electron-withdrawing groups in the para position of the benzaldehyde increases the dipolarophile reactivity. This work was also extended to the use of meso-tetrakis(pentafluorophenyl) porphyrin as a dipolarophile, allowing new flavone-dihydroporphyrin conjugates to be prepared. |
DOI |
http://dx.doi.org/10.1002/ejoc.201101185 |
ISBN |
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Publisher |
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Book Title |
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ISSN |
1434-193X |
EISSN |
1099-0690 |
Conference Name |
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Bibtex ID |
ISI:000299294000017 |
Observations |
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