Ring Transformation of Chromone-3-Carboxamide under Nucleophilic Conditions
作者:Magdy A. Ibrahim
DOI:10.5935/0103-5053.20130220
日期:——
The chemical reactivity of chromone-3-carboxamide was studied towards a series of nitrogen and carbon nucleophiles. Treatment of carboxamide with some primary amines gave chromane-2,4-diones. Condensation of carboxamide with hydrazine hydrate, phenyl hydrazine and hydroxylamine hydrochloride afforded chromenopyrazoles and chromenoisoxazole, respectively. Reaction of carboxamide with guanidine hydrochloride
An Efficient Route for Synthesis and Reactions of Seleno-[2, 3-c]coumarin
作者:Shams H. Abdel-Hafez、Ahmed Elkhateeb、Adel A. Gobouri、Islam H. El Azab、Gilbert Kirsch
DOI:10.3987/com-16-13445
日期:——
Synthesis of new selenium-containing coumarin moiety via the reaction of 4-chloro-2-oxo-2H-chromene-3-carbonitrile with selenium and sodium borohydride gave 3-cyano-4-coumarinselenol which reacted with different halo-acids, such as chloroacetonitrile, ethyl chloroacetate and chloroacetamide to give the corresponding 3-amino-4-oxo-4H-seleno[3,2-c]chromene derivatives. Hydrazonolysis of the obtained new ethyl 3-amino-4-oxo-4H-seleno[3,2-c]hyphen chromene-2-carboxylate afforded the corresponding hydrazino compound. The hydrazino compound was used as a versatile precursor for synthesis of new other heterocyclic compounds containing selenocoumarin moiety. The newly synthesized compounds were characterized using the spectroscopic tools (IR, H-1 NMR, C-13 NMR and mass spectroscopy) as well as microanalysis.
Mulwad; Shirodkar, Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 2002, vol. 41, # 6, p. 1263 - 1267
作者:Mulwad、Shirodkar
DOI:——
日期:——
Rearrangements of N-alkyl-/aryl-nitrones derived from 4-oxo-4H-1-benzopyran-3-carboxaldehyde––a solvent-dependent process
作者:Tarun Ghosh、Chandrakanta Bandyopadhyay
DOI:10.1016/j.tetlet.2004.06.033
日期:2004.8
C-(4-Oxo-4H-1-benzopyran-3-yl)-N-alkyl-/aryl-nitrones derived from 4-oxo-4H-1-benzopyran-3-carboxaldehyde, rearrange to 2-alkyl-/aryl-amino-3-formylchromone and/or 3-(alkyl-/aryl-aminomethylene)chroman-2,4-dione depending upon the reaction medium. 3-(Alkylaminomethylene)chroman-2,4-dione has been utilized in the synthesis of 1-benzopyrano[3,4-d]isoxazole-4-one. (C) 2004 Elsevier Ltd. All rights reserved.
Moorty,S.R. et al., Indian Journal of Chemistry, 1973, vol. 11, p. 854 - 856