53847-58-8Relevant articles and documents
A Simple Route for the Synthesis of Chlorosubstituted Arylazobenzenes, Arylazonaphtalenes, and Arylazopyrazoles
Guenther, R.,Jaehne, E.,Hartmann, H.,Schulze, M.
, p. 945 - 954 (2007/10/02)
The reaction of arylazophenoles and arylazohydroxypyrazoles (or their tautomer hydrazones) 10, 11, and 15 with POCl3 in dimethylformamide yields chlorosubstituted arylazobenzenes or arylazopyrazoles 12, 13 and 16, resp., in moderate to high yields.The substitution of the OH-group by the Cl-moiety is favoured by acceptor substituents in the aryl fragments ortho- and/or para-linked to the azo group.In case that arylazocompounds derived from resorcinol are used the substitution reaction runs in a stepwise manner giving raise to the formation of o-hydroxy-p-chlorosubstit uted azo compounds 18 primarily and then of dichlorosubstituted azo compounds 19.
