Nitrothiazoles, formation

The conditions required for the isolation of such nitroamines have been described [204], In concentrated sulfuric acid they readily rearrange to 2-amino-5-nitrothiazoles. The isomerization rate depends strongly on the sulfuric acid concentration [204], Thus, the formation of 2-amino-5-nitrothiazoles may be the result both of direct electrophilic substitution in the thiazole ring and of the aforementioned rearrangement. 

With the help of UV spectroscopy the formation of palladium II complexes with 5-nitrothiazolyl-2-azoderivatives has been investigated [1169], For the identification of 2-organylamino-5-nitrothiazoles UV-spectra were used [1173],... 

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