Azophosphonates
Azophosphonates (also: Arylazophosphonate) are azo compounds , which are composed of an aromatic part ( aromatics ) and a phosphonate part ( phosphonate ) and are covalently linked via an azo group.
Alternative terms used in the literature are azophosphonic acid esters and arylazophosphoric acid esters. This class of compounds was only discovered by F. Suckfüll and H. Haubrich in 1958, exactly one century after the first synthesis of a diazonium salt by Johann Peter Grieß .
synthesis
Azophosphonates can be prepared by NP azo coupling of an aromatic diazonium salt with a dialkyl phosphite in the presence of auxiliary bases . The synthesis can be carried out with yields of over 80% largely independently of the aromatic residue .
properties
Spectroscopic data
As aromatic azo compounds, azophosphonates are composed of a chromophoric and auxochromic group. Azophosphonates are intensely colored compounds. In substance or in a concentrated solution, they have a red inherent color that turns increasingly yellow with increasing dilution.
Stability and Reactivity
Azophosphonates are described in the literature as relatively stable compounds. At temperatures above 150 ° C , the thermolysis could be observed in substance with the formation of gaseous products.
Individual evidence
- ↑ a b F. Suckfüll, H. Haubrich, Angew. Chem. 70, 238 (1958)
- ↑ H.Bock, Angew. Chem. 77, 469 (1965)
- ↑ F. Suckfüll, H. Haubrich, DB Patent 1008313 (1955)
- ↑ P. Grieß, Liebigs Ann. Chem. 106, 123 (1858)
- ↑ a b J. Fabian, H. Hartmann: Light Absorption of Organic Colorants , Springer, Berlin 1980
- ↑ a b T. G. Valeeva, YA Levin, Zhur. Obsh. Khim. 55, 2286 (1985)