C–H Amination of Nitro Azaheterocyclic Compounds by Vicarious Nucleophilic Substitution

Abstract

Various nitro azaheterocyclic compounds were subjected to C–H amination by vicarious nucleophilic substitution with 4H-1,2,4-triazol-4-amine (ATA). The aminated products were characterized by NMR, mass spectroscopy, and single-crystal X-ray diffraction analyses. The substrates examined gave moderate to excellent yields (30–88%) and showed good regioselectivities. This protocol offers the advantages of mild conditions, a short reaction time (2–4 hours), and an inexpensive, commercially available, and less-toxic amination reagent; moreover, no additional catalyst or reagent is needed. A possible reaction mechanism is discussed.

Key words

C–H functionalization - amination - nitro azaheterocyclic compounds - vicarious nucleophilic substitution - 4H-1,2,4-triazol-4-amine - crystal structure

Publication History

Received: 15 September 2021

Accepted after revision: 19 October 2021

Accepted Manuscript online:
19 October 2021

Article published online:
19 November 2021

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