Alizarin Quinoline

The first quinoline derivative obtained by the process (a) was the dye alizarin blue (Prud homme, 1877). f -Nitroaliza,rin was heated with glycerol and sulphuric acid. The constitution of the product was established by Graehe ... 

The hydroxylation of aromatic compounds takes place on heating with solid potassium hydroxide of compounds with low electron density in the ring and occurs in positions prone to nucleophilic attack. Nitrobenzene is converted into o-nitrophenol on heating with potassium hydroxide for 2 h at 60-70 °C (yield 45%) [485]. Quinoline gives carbostyril (2-hydroxyqui-noline) on heating with potassium hydroxide for 3 h at 225 °C (yield 77%) [486], A historically important reaction is the hydroxylation of both a- and P-anthraquinonesulfonic acid by alkali fusion to yield alizarin (1,2-dihy-droxyanthraquinone). 

This dyestuff is prepared by heating -nitroalizarin with glycerine and sulphuric acid. It is peculiar in so far that it possesses the lake-forming properties characteristic of the alizarin dyes, and is at the same time a weak base. Alizarin blue was discovered by Prud homme [28], and the determination of its constitution by Graebe [29] led to the synthesis of quinoline by Skraup from glycerine, nitrobenzene, and aniline. 

Alizarin blue has the composition Ci7H9NO, and stands in the same relation to alizarin as quinoline to benzene. 

Alizarine Blue. 5 Dihydroxynaphtho[2,2 /]quin-oiine-7,l2 dione 7.8-dihydroxy-5,6-phthaly[quinoline Alizarin Blue R C.I. 67410- C 7H9N04 mol wt 291-25. C 70,10%, H 3.12%, N 4.81%, O 21,97%. Prepn from 3-nitro-alizarin, glycerol, and coned sulfuric acid Auerbach, J. 

Alizarin Blue complexes of Al, Ga, and In chlorides have been synthesized for the first time (complexing to the metal occurs via both the 8-hydroxy-quinoline and a-hydroxyanthraquinone moieties. ... 

Dihydroxynaphtho[2,3- quinoline-7,12-dione Alizarin Blue C17H9NO4 568-02-5 291.258 br-viol nd (bz) 269 vs bz, gl HOAc... 

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