Synthesis of 2-(2-hydroxybenzoyl)-4H-furo[3,2-c]chromen-4-one has been accomplished by the reaction of 3-halochromone with 2-aminochromone. In this reaction, 2-aminochromone acts as a masked 4-hydroxycoumarin.
A DDQ-mediated tandem annulation of 2-aminochromones with 1,3-diarylpropenes is disclosed, which provides the azaxanthones in moderate to good yields. The oxidative coupling, intramolecular cyclization and dehydro-aromatization might be involved in this high atom-efficiency reaction.
Synthesis of 2,2′-Diaminobischromones Using a Modified Procedure for the Rearrangement of 5-(2-Hydroxyphenyl)isoxazole to 2-Aminochromone
作者:Chandrakanta Bandyopadhyay、Tarun Ghosh、Satyajit Saha
DOI:10.1055/s-2005-869965
日期:——
A modified procedure for the rearrangement of 5-(2-hydroxyphenyl)isoxazoles 6a-e to 2-aminochromones 8a-e was developed and this procedure was utilised in the synthesis of hitherto unreported bischromones 3a-c. The isoxazoles 6a-e were prepared regioselectively from aminovinylketones 5.
One-pot synthesis of chromeno[2,3-<i>b</i>]isoindolo[1,2-<i>e</i>]pyrrole-12,13-dione derivatives by sequential reaction of ninhydrin, 2-aminochromen-4-ones and arylamines
ABSTRACT Stirring an equimolar mixture of ninhydrin 1 and 2-aminochromen-4-ones 2 in CH3COOH at room temperature produced 6a,11a-dihydroxy-6H-chromeno[2,3-b]indeno[2,1-d]pyrrole-11,12(6aH,11aH)-diones 3, which on heating with aromatic amines 6 in acetic acid produced 11b-hydroxy-7-N-arylimino-6H-chromeno[2,3-b]isoindolo[1,2-e]pyrrole-12,13(11bH)-diones 7. GRAPHICAL ABSTRACT
Reactions of 2-amino-4<i>h</i>-1-benzopyran-4-one with 4-oxo-4<i>h</i>-1-benzopyran-3-carbaldehydes
作者:Tarun Ghosh、Chandrakanta Bandyopadhyay
DOI:10.1002/jhet.5570430603
日期:2006.11
The title aldehyde 1 reacts smoothly with the enamine moiety of 2-aminochromone 2 to produce hitherto unreported 3-(2-hydroxybenzoyl)-5H-1-benzopyrano[2,3-b]pyridin-5-one (azaxanthone) 5. This reaction has been extended for the synthesis of bisazaxanthone 9.
标题醛1分发生反应顺利与烯胺部分2 -aminochromone 2以产生迄今未报告的3-(2-羟基苯甲酰基)-5- ħ -1-苯并吡喃并[2,3- b ]吡啶-5-酮(azaxanthone)5。该反应已扩展为合成双氮杂蒽酮9。