3-Amino-4-arylazopyrazoles: CT complexation and a novel synthesis of pyrazolo[2,3-a]quinazolines

Article abstract of DOI:10.1002/ardp.19923250704

3,5-Diamino-4-arylazopyrazoles 1a-d form charge-transfer (CT) complexes with chloranil (CHL), fluoranil (TFQ) and react with 2,3-dicyano-5,6-dichlorobenzoquinone (DDQ) to yield pyrazolo[2,3-a]quinazoline derivatives 4. 5-Amino-3-phenyl-4-arylazopyrazole 2a-d form CT-complexes only with DDQ.