Direct Amination of Nitroquinoline Derivatives via Nucleophilic Displacement of Aromatic Hydrogen

Abstract

The vicarious nucleophilic substitution of hydrogen (VNS) reaction in electron-deficient nitroquinolines was studied. Properties of all new products have been characterized by several techniques: MS, HRMS, FTIR, GC-MS, electronic absorption spectroscopy, and multinuclear NMR. The structures of 4-chloro-8-nitroquinoline, 8-(tert-butyl)-2-methyl-5-nitroquinoline, 9-(8-nitroquinolin-7-yl)-9H-carbazole and (Z)-7-(9H-carbazol-9-yl)-8-(hydroxyimino)quinolin-5(8H)-one were determined by single-crystal X-ray diffraction measurements. The 9-(8-nitroquinolin-7-yl)-9H-carbazole and (Z)-7-(9H-carbazol-9-yl)-8-(hydroxyimino)quinolin-5(8H)-one illustrate the nitro/nitroso conversion within VNS reaction. Additionally, 9-(8-isopropyl-2-((8-isopropyl-2-methyl-5-nitroquinolin-6-yl)methyl)-5-nitrosoquinolin-6-yl)-9H-carbazole is presented as a double VNS product. It is postulated that the potassium counterion interacts with the oxygen on the nitro group, which could influence nucleophile attack in that way.

Synthesis and Spectroscopic Characterization of Selected Phenothiazines and Phenazines Rationalized Based on DFT Calculation

“…We have recently reported the direct oxidative condensation to introduce the carbon-nitrogen bond by a one-step method [ 35 ]. To synthesize the symmetrical phenazine 5 and the unsymmetrical phenazines 6 , we applied two other types of chemical transformations.…”

“…The synthesis of 2,8-dimethylquinoline, 8-( iso propyl)-2-methylquinolin-5-amine ( 4a ) and 2,8-dimethylquinolin-5-amine ( 4b ) followed our procedure described in the literature [ 35 ].…”