A new safe source of hydrazoic acid has been developed with the participation of ZIOC

In recent decades, alkyl azides have attracted increasing interest due to the possibility of their application both in organic synthesis and as high-energy compounds. In addition, there is an explosive growth in their use in biology and medicine as initial substrates for copper-catalyzed azide-alkyne cycloaddition (“click reaction”), which makes it possible, for example, to easily and quickly modify biological objects (peptides, nucleosides, etc.). ) with fluorescent labels. The classical method for the synthesis of alkyl azides is the nucleophilic substitution reaction using NaN3 as the source of the azide group. The main disadvantages of this approach are the need to use toxic solvents and, as a rule, harsh reaction conditions. In addition, under acidic conditions, sodium azide generates poisonous and explosive hydrogen azide. For these reasons, the development of methods for the efficient and environmentally friendly preparation of alkyl azides is an urgent task of organic chemistry.

With the participation of the researchers from the Laboratory of Directed Functionalization of Organic Molecular Systems, a method was proposed for the synthesis of 4-(dimethylamino)pyridinium azide, a stable, non-explosive, low-hygroscopic source of hydrazoic acid/azide ion, soluble in both protic and aprotic organic solvents. It should be especially noted that the synthesis of this compound can be successfully scaled up. The efficiency of using 4-(dimethylamino)pyridinium azide was demonstrated by the example of cyclopropane and epoxy ring opening reactions, nucleophilic substitution, and (3+2)-cycloaddition, including those realized in the context of telescopic synthesis.

Source:

Ivan A. Andreev, Maksim A. Boichenko, Nina K. Ratmanova, Olga A. Ivanova, Irina I. Levina, Victor N. Khrustalev, Igor A. Sedov, Igor V. Trushkov 4-(Dimethylamino)pyridinium Azide in Protic Ionic Liquid Media as a Stable Equivalent of Hydrazoic Acid. Adv. Synth. Catal., 2022, 364, 2403-2415. DOI: 10.1002/adsc.202200486.