159971-86-5Relevant academic research and scientific papers
A new heterocyclization in the series of acetylenic derivatives of anthraquinone
Shvartsberg,Ivanchikova,Fedenok
, p. 1714 - 1719 (2007/10/03)
2-Alkynyl-1-amino-9,10-anthraquinones react with HNO2 in a mixture of dilute HCl and dioxane at 20°C to give 1,1-dichloroalkyl-1H-3-naphtho[2,3-g]indazole-6,11-diones. This reaction differs from the known cyclization of ortho-alkynylbenzenediazonium salts involving the formation of a pyridazine ring (the Richter synthesis of 4-hydroxy- and 4-halocinnolines).
An unusual direction of the Richter synthesis. 1H-naphtho[2,3-g]indazole-6,11-diones
Shvartsberg, Mark S.,Ivanchikova, Irena D.,Fedenok, Lidiya G.
, p. 6749 - 6752 (2007/10/02)
Diazotization of 2-acetylenic derivatives of 1-aminoanthraquinone followed by intramolecular cyclization leads to the formation in good yields of 1H-3-acyl- or 1H-3-(1,1-dichloroalkyl)naphtho[2,3-g]indazole-6,11-diones, rather than 3-substituted 4-hydroxy
