136806-22-9Relevant academic research and scientific papers
Phosphorylation and amine-induced dephosphorylation of 4-chlorocoumarin-3- carboxaldehyde and 4-chloro-3-(β,β-dicyanoethenylidene)coumarin
Khidre, Maha Darwish
, p. 2147 - 2158 (2007/10/03)
4-Chlorocoumarin-3-carboxaldehyde (1) and 4-chloro-3-(β,β- dicyanoethenylidene)coumarin (2) produce their respective 1:1 phosphonate adducts (5a-c) and (6a-c) upon reaction with the appropriate dialkylphosphonates (3a-c). Compounds 5 undergo dechlorination and dephosphorylation upon reaction with certain primary aliphatic amines to yield 9 (or 10) according to the nature of the amine used. Compounds 1 and 2 undergo dechlorination through reaction with hexamethyl-phosphorustriamide 4 to give the respective 4-dimethylamino-derivatives (11a and 11b). Structural reasonings for the new compounds are based on compatible analytical and spectroscopic measurements. The mechanism for formation of compounds 11 also is discussed.
Heterocyclic -Condensed Coumarins from 4-Azido-3-coumarincarbaldehydes
Steinfuehrer, Thorsten,Hantschmann, Achim,Pietsch, Michael,Weissenfels, Manfred
, p. 23 - 28 (2007/10/02)
4-Azido-3-coumarincarbaldehydes 2a-d are useful starting materials for syntheses of a variety of 3,4-disubstituted coumarins as well as heterocyclic -fused coumarins, e. g. isoxazoles, pyrazoles and 1,5-diazepines, under mild conditions.In these reacti
