20269-39-0

Upstream product

• 1709-63-3 anthracene-1,4,9,10-tetraone 
• 107-15-3 ethylenediamine 
• 81-64-1 1,4-dihydroxy-9,10-anthracenedione 

Relevant academic research and scientific papers

A Novel Ring-closure Reaction between 1,4-Dihydroxyanthraquinone and Diamines Promoted by Copper Ions

The reaction of 1,4-dihydroxyanthraquinone (DHAQ,1) with various diamines were carried out in the presence of CuCl2.Primary 1,2-ethylenediamines or 1,2-cyclohexanediamine afforded the ring-closure products, 6-hydroxy-1,2,3,4-tetrahydronaphthoquinoxaline-7,12-dione derivatives, in good yields of 70-98percent.On the other hand, in the cases of N-alkylethylenediamines or 2-(alkylamino)ethanols, the major products were the 2-aminated 1,4-dihydroxyanthraquinones.The direct 2-amination of 1 was greatly inhibited when an alkyl group was introduced to the amino group because of its steric requirement.The role of copper ions, the effect of a steric requirement of the N-alkyl substituent of amines, and the effect of the chain length of alkanediamines in the reaction of 1 with amines were studied.It was proposed that the reaction was initiated by the direct 2-amination of 1 via the copper complex, followed by the intramolecular nucleophilic substitution of the 2-amino group on the 2-alkylamino substituent to give the ring-closure product.

A NOVEL RING CLOSURE REACTION BETWEEN 1,4-DIHYDROXYANTHRAQUINONE AND ETHYLENEDIAMINE PROMOTED BY COPPER IONS

The reaction of 1,4-dihydroxyanthraquinone with ethylenediamine in the presence of Cu(I)Cl or Cu(II)Cl2 gave 6-hydroxy-1,2,3,4-tetrahydronaphtho-(2,3-f)-quinoxaline-7,12-dione in quantitative yield at ambient temperature.The reaction was promoted greatly by copper ions.The possible mechanism and the role of copper ions were discussed.