Dehydrogenation of the NH−NH Bond Triggered by Potassium tert‐Butoxide in Liquid Ammonia

Abstract

A novel strategy for the dehydrogenation of the NH-NH bond is disclosed using potassium tert-butoxide (tBuOK) in liquid ammonia (NH ) under air at room temperature. Its synthetic value is well demonstrated by the highly efficient synthesis of aromatic azo compounds (up to 100 % yield, 3 min), heterocyclic azo compounds, and dehydrazination of phenylhydrazine. The broad application of this strategy and its benefit to chemical biology is proved by a novel, convenient, one-pot synthesis of aliphatic diazirines, which are important photoreactive agents for photoaffinity labeling.

tBuOK-triggered bond formation reactions

“…Components bearing N]N bonds are ubiquitous motifs in therapeutic agents, food additives, dyes, pigments, photochemical switches, and radical reaction initiators. [32][33][34] A previous report using tBuOK was conducted in liquid ammonia which is dangerous and need to operate at À75 C. 35 On the contrary, simply sealed the starting material in a pressure tube and heat at 60 C we can obtain 95% azobenzene from hydrazobenzene. Then a series of aromatic azo compounds were successfully prepared in excellent yields in short reaction time ( Fig.…”

Recent Applications of Diazirines in Chemical Proteomics

“…Subsequent oxidation to the diazirine can occur under similar conditions to those discussed above.M ost recently,b ase promoted oxidations of the diaziridine using molecular oxygen (O 2 )i nt he form of air have been reported, and, in certain cases, have allowed the combination of steps into ao ne-pot protocolfor the synthesis of alkyl diazirines. [22] In addition to improved procedures for the synthesis of diazirines, growing awareness of their compatibility with common functional group interconversions has led to their increased use in multi-step synthetic sequences. In the particularc ase of TPDs, these include ag eneral insensitivity towards strong acid or base, enabling base promoted alkylationreactions as well as Lewis acid mediated electrophilic aromatic substitution.…”

Chitosan-derived N-doped carbon catalysts with a metallic core for the oxidative dehydrogenation of NH–NH bonds

“…18 Therefore, it is important to precisely optimize the synergistically active metal sites and N-doped porous structures simultaneously over carbon-based catalysts for better exposure in dehydrogenation reactions. [19][20][21] In 2010, Titirici and coworkers described the hydrothermal treatment of chitosan, followed by calcination, for the preparation of carbonaceous materials. 22 Later, it was shown that chitosan could serve as an excellent precursor to generate Ndoped graphene.…”