On the chichibabin amination of quinoline and some nitroquinolines

Abstract

Quinoline is aminated into 2‐aminoquinoline (55‐60%) when treated with potassium amide/liquid ammonia/potassium permanganate at −65°. When the amination is carried out by allowing the solution of quinoline in potassium amide/liquid ammonia to raise from −60° to + 15° before addition of potassium permanganate, the main product is 4‐aminoquinoline. Using as reagent liquid ammonia/potassium permanganate (thus without the presence of potassium amide) 3‐nitroquinoline is exclusively aminated at −40° into 4‐amino‐3‐nitroquinoline. Using the same conditions, from 4‐nitroquinoline 3‐amino‐4‐nitroquinoline is obtained. The mechanism of these amination reactions is discussed.

Study of the regioselectivity of vicarious nucleophilic amination of mononitroquinolines with 1,1,1-trimethylhydrazinium iodide (TMHI)

“…These changes of the chemical shifts (∆δ = 3.24 −5.22 ppm) are comparable to those reported earlier for the amino σ adducts detected in oxidative dehydroamination of nitroquinolines [4][5][6] . In the case of 5-nitro-(1b) and 8-nitroquinoline (1e) we did not observe NMR signals from the σ adducts linked at the position…”

Vicarious nucleophilic amination of nitroquinolines by 1,1,1‐trimethylhydrazinium iodide

“…This determined unequivocally the position of the amino group in 2a (2 or 4) carried out by comparison of its properties (R F , mp and 1 H NMR and IR spectrum) with reference to the sample obtained by oxidative amination [17] (Scheme 1).…”

“…These reactions can proceed by nucleophilic replacement of aromatic hydrogen, S N H substitution, by oxidative (ONSH) or vicarious amination (VNS). Wo niak et al, aminated x-mononitroquinolines (x = 2-8) [15,17] in a solution of potassium permanganate in liquid ammonia -33 °C. The oxidative amination occurs very selectively giving only ortho substitution relative to the nitro group, aminonitroquinolines with moderate to low yields [15,17], except 2-nitro-and 8-nitroquinoline, which was found to be unreactive [15].…”

“…Wo niak et al, aminated x-mononitroquinolines (x = 2-8) [15,17] in a solution of potassium permanganate in liquid ammonia -33 °C. The oxidative amination occurs very selectively giving only ortho substitution relative to the nitro group, aminonitroquinolines with moderate to low yields [15,17], except 2-nitro-and 8-nitroquinoline, which was found to be unreactive [15]. Hasegawa et al, [3] reported the amination of 5-nitro-, 6-nitro-, 7-nitroand 8-nitroquinoline using hydroxylamine in potassium hydroxide as an aminating agent, obtaining a novel product, furazanoquinoline, besides the known amino derivatives substituted in ortho and/or para positions to the nitro group [3].…”

Amination of 4‐nitropyridazine 1‐oxides by liquid ammonia/potassium permanganate

“…This amination-oxidation procedure has been found to be very useful especially for the preparation of aminoazaaromatics, which by the classical Chichibabin procedure (using sodamide or potassium amide in an aprotic solvent) [2] cannot be obtained or only with difficulty. The synthetic utility of our method is demonstrated by the broad variety of azaaromatics which can be converted into the corresponding amino compounds: 2-aminoquinoline from quinoline (at -60') [3], 4-aminoquinoline from quinoline (at + 20') [3], 4-aminopyrimidine from pyaminopyrazine from pyrazine [4], 5-amino-l,2,4-triazine go covalent amination at C-5, when dissolved in liquid ammonia [lO,ll]. We became interested whether by treatment of these covalent adducts with potassium permanganate the amino group could be introduced at C-5 in those 4-nitropyridazine 1 oxides [12].…”