Methylamine-potassium permanganate

Tliis methodology has also been extended to the use of liquid methylamine/ potassium permanganate (LMA/PP system). When this system is applied to a number of 3-nitro-l,8-naphthyridines (92a-92g), the C-4 position could be successfully substituted by methylamino group yielding 93a-93f. Tire intermediary 4-methylamino-[Pg.305]

As discussed before, in liquid ammonia/potassium permanganate nucleo-phugal substituents at C-2, such as ones present in the naphthyridines (84c, 84e, 84h, 84i, 841, and 84m), could not be replaced by the amino group only SnH substitution takes place. However, it has been observed that in the reaction of the 2-chloro-3-nitro-l,8-naphthyridine (92c) with liquid methylamine/potassium permanganate S H substitution as well as methylamino-dechlorination takes place, yielding 2,4-bis-(methylamino)-3-nitro-l,8-naphthyridine (93c). 

Chlormezanone Chlormezanone, 2-(p-chlorophenyl)-tetrahydro-3-methyl-4H-l,3-tiazin-4-on-1,1-dioxide (5.2.8), is synthesized by joint condensation of mercaptopropionic acid, methylamine, and 4-chlorobenzaldehyde, evidently through the intermediate stage of formation of 4-chlorobenzylidenemethylamine, giving the aminothioacetal 2-(p-chlorophenyl)-tetrahydro-3-methyl-4H-l,3-tiazin-4-one (5.2.7). Oxidation of the sulfur atom using potassium permanganate gives chlormezanone (5.2.8) [62,63]. 

Dinitro[l,8]naphthyridine and its 2-substituted derivatives are dehydro-methylaminated with a solution of potassium permanganate in liquid methylamine to afford the corresponding mono- or bis-methylamino-3,6-dinitro[l,8]naphthyridines (Scheme 7) <2000CJC950>. When the 2-substituent is either chlorine or OMe, then some substitution by NHCH3 also occurs. Quantum-chemical calculations have shown that the reaction is controlled by the interaction of the frontier MOs. 

Table III. Products and Yields Obtained in the Methylamination of Nitro- and Dinitroquinolines by Methylamine (—7 °C)/Potassium Permanganate...

Lobelanine on oxidation with potassium permanganate produces 2 moles of benzoic acid and, therefore, must contain two monosubstituted benzene rings. When lobelanine is heated to 140° with molten benzoic acid or at 125° with excess dilute hydrochloric acid, it gives rise to acetophenone, a product also characteristic of the decomposition of lobeline. Heating with hydrochloric acid also produces methylamine and fluorene whereas heating under pressure with alcoholic potassium hydroxide yields a mixture of methylamine, benzhydrol, and phenylmethylcarbinol. The HCl... 

Nitro-l,5-naphthyridines were oxidatively methylaminated in liquid methyl-amine as solvent in the presence of potassium permanganate [161]. Direct oxidative amination of 3-nitronicotinate with formanilide proceeds at the position 6 of the pyridine ring, resulting in the formation of anilinopyridine (Scheme 53) [162]. 

Beginning with furan (15), exposure to bromine in a suspension of potassium carbonate in methanol gave the dimethoxy furan 16. Next, treatment of 16 with potassium permanganate yielded cw-dihydroxylated acetal 17. The acetal functionality was converted to the transient dialdehyde 18, which underwent the title reaction upon exposure to acetonedicarboxylic acid and methylamine under simulated physiological conditions to give teloidinone (19). 

Potassium permanganate acetic acid N-Demethylation via formamides Formamides from methylamines with and without simultaneous oxidation of methylene to keto groups... 

The intermediate products (I) and (II) lose water, forming hydrohydrastinine and oxyhydrastinine respectively. Alkaline permanganate converts oxyhydrastinine into hydrastinic acid (III), C HgOgN, needles, m.p. 164° this in turn is oxidised by dilute nitric acid to hydrastic acid methylimide (IV), CJ0H7O4N, m.p. 227-8°, which, when warmed with potassium hydroxide solution, furnishes methylamine and hydrastic acid (V). 

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