
%0 Journal Article
%A Paul, DB 
%A Rodda, HJ 
%T Pyridopyridazines. III. The synthesis and reactions of 5- and 8-Chloropyrido[2,3d]pyridazine
%J Australian Journal of Chemistry
%D 1969/08/01
%V 22
%N 8
%P 1759-1772
%K 
%R https://doi.org/10.1071/CH9691759
%U https://www.publish.csiro.au/paper/CH9691759 
%X Pyrido[2,3-d]pyridazin-5-one and -8-one have been synthesized by several methods and converted into 5- and 8-chloropyrido[2,3- d]pyridazine. These latter compounds were also prepared by dehydrazination of the requisite chlorohydrazino- pyrido[2,3-d]pyridazines. Some nucleophilic reactions of the chloropyrido[2,3-d]- pyridazines have been studied. Cyclization of 5- and 8-hydrazino- and 5,8-dihydrazino-pyrido[2,3-d]pyridazine with formic acid has led to the new heterocyclic compounds pyrido[2,3-d]- and pyrido[3,2-d]-s- triazolo[4,3-d]pyridazine. 
