N-amination and subsequent oxidation of some fused imidazoles and triazoles

Abstract

I l l )short time, but it slowly deposited ammonium tolueiie-9sulphonate. Surprisingly, when the solution was boiled under reflux and the precipitated ammonium toluene-psulphonate filtered off, evaporation of the filtrate gave

Serendipitous Synthesis of (tert‐Butyl‐NNO‐azoxy)acetonitrile: Reduction of an Oxime Moiety to a Methylene Unit

“…80-83°C). To understand the scope of the reduction of the oxime moiety to a methylene unit, amination of the Na salt of ethyl cyano(hydroxyimino)acetate (12) was carried out under the same conditions as for the amination of Na salt 9a (Scheme 9; a two-phase system CH 2 Cl 2 /H 2 O in the presence of the phasetransfer catalyst Et 4 NBF 4 ). However, a Forster reaction took place to give diazo compound 13 in 77 % yield.…”

A convenient synthesis of 2-substituted [1,2,4]triazolo-[1,5-a]quinolines and [1,2,4]triazolo[5,1-a]isoquinolines

“…The starting compounds of this reaction, 1,2-diaminoquinolinium tosylate 4 19 and 1,2-diaminoisoquinolinium tosylate 9 19 are readily available from 2-aminoquinoline and 1-aminoisoquinoline by direct N-amination procedure using O-tosylhydroxylamine 20 according to our previously published procedure. 21 When a solution of the tosylates 4 or 9 in methanol is mixed with an aliphatic or aromatic aldehyde 2 and treated with aqueous potassium hydroxide at room temperature the respective 2-substituted fused [1,2,4]triazoles 8 and 13 are obtained within a few hours (Scheme 2).…”

“…19 To a stirred solution of quinolin-2-ylamine 25 (0.5 g, 3.5 mmol) in dichloromethane (5 mL) was added a solution of O-tosylhydroxylamine 20 (0.7 g, 3.9 mmol) in dichloromethane (5 mL) at rt. Within a few minutes a precipitate began to separate.…”

An Energetic N‐Oxide and N‐Amino Heterocycle and its Transformation to 1,2,3,4‐Tetrazine‐1‐oxide

“…The aqueous filtrate was evaporated to dryness, extracted with hot ethanol, and recrystallized from nitromethane yielding 2. Freshly prepared pulverized ethyl O-p-tolylsulphonylacetohydroximate (1.8 g, 7.0 mmol) [23] was added to perchloric acid (32 mL, 60 %) and stirred for two h under ambient conditions. This mixture was poured into a ice/water mixture (200 mL) and the ice was allowed to melt followed by the extraction with five portions (50 mL) of dichloromethane.…”