Synthesis of 4H,5H-pyrano [3,2-c] (1) benzopyran-4,5-diones

Authors
Bhagat, RD Mulwad, VV
Citation
Rd. Bhagat et Vv. Mulwad, Synthesis of 4H,5H-pyrano [3,2-c] (1) benzopyran-4,5-diones, I J HET CHE, 9(2), 1999, pp. 123-126
Citations number
10
Categorie Soggetti
Organic Chemistry/Polymer Science
Journal title
INDIAN JOURNAL OF HETEROCYCLIC CHEMISTRY
ISSN journal
09711627 → ACNP
Volume
9
Issue
2
Year of publication
1999
Pages
123 - 126
Database
ISI
SICI code
0971-1627(199910/12)9:2<123:SO4[(B>2.0.ZU;2-4
Abstract
Claisen condensation of 3-acetyl-4-hydroxycoumarins with different esters i n the presence of sodium/ether gave 4-hydroxy 3[1 -substituted-1,3-dioxo pr opyl] benzopyran-2-ones (IIa-p) which on further cyclization with sodium ac etate and acetic acid gave corresponding 4H, 5H-pyrano [3,2-c](1) benzopyra n-4,5-diones (IIIa-p). Alternate route for the synthesis of 7-methyl-4-hydr oxy 3 [1-phenyl-1,3-dioxo prspyl] benzopyran-2-one (IIg) is also suggested.