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The Thermal Instability of 2,4 and 2,6-N-Alkylamino Disubstituted and 2-N-Alkylamino Substituted Nitrobenzenes in Weakly Alkaline Solution: sec-Amino Effect.

ABSTRACT: We report herein the preparation of two families of secondary amines by the reactions of two equivalents of monoamines with either 2,4 or 2,6-difluoronitrobenzenes in N,N-dimethylacetamide in the presence of anhydrous potassium carbonate, as precursors of biologically important nitric oxide donating N-nitrosamines. In both instances, these compounds could be prepared in quantitative yield when the reaction temperature was held below 130°C. Above this reaction temperature, an unexpected cyclization reaction between the nitro and newly formed adjacent secondary amine group leads to the formation of benzimidazole or quinoxaline rings in low yields. Reasonable reaction mechanisms for the cyclization reaction are proposed.

SUBMITTER: Walczak C

PROVIDER: S-EPMC4469390 | biostudies-other | 2015 May

REPOSITORIES: biostudies-other

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The Thermal Instability of 2,4 and 2,6-N-Alkylamino Disubstituted and 2-N-Alkylamino Substituted Nitrobenzenes in Weakly Alkaline Solution: sec-Amino Effect.

Walczak Christopher C Payne Thomas J TJ Wade Colin B CB Yonkey Matthew M Scheid Melissa M Badour Alec A Mohanty Dillip K DK

Journal of heterocyclic chemistry 20150501 3

We report herein the preparation of two families of secondary amines by the reactions of two equivalents of monoamines with either 2,4 or 2,6-difluoronitrobenzenes in N,N-dimethylacetamide in the presence of anhydrous potassium carbonate, as precursors of biologically important nitric oxide donating N-nitrosamines. In both instances, these compounds could be prepared in quantitative yield when the reaction temperature was held below 130°C. Above this reaction temperature, an unexpe ...[more]

PMID: 26097254

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