This work discloses a new methodology for the site-selective direct installation of a nitro group at the benzene ring of 2H-indazoles with excellent selectivity towards the synthesis of 7-nitroindazole derivatives.
The electrochemical C3 acyloxylation reactions of 2H-indazoles with carboxylic acids in the presence of K2CO3 were successfully developed, which were green and sustainable without transition-metal catalysts and stoichiometric oxidants.
An unprecedented metal-free regioselective halogenation of 2H-indazoles is reported, and not only realizes the highly selective synthesis of mono-halogenated products, but also complete poly-halogenations.
Bromoaryl compounds have attracted great attention in organic chemistry, especially for the synthesis of pharmaceutical intermediates.
The recent advances in the construction of N–N bond from primary and secondary amines via direct oxidation method, is an interest of both academia and industry for preparing the organic frameworks such as azos, hydrazines, indazoles and triazoles.