2273-09-8

Upstream product

• 62-53-3 aniline 
• 103-71-9 phenyl isocyanate 
• 1254381-14-0 1-(1,3,4-triphenyl-4,5-dihydro-1H-1,2,4-triazol-5-yl)propan-1-one 
• 55305-43-6 N-cyano-N-phenyl-p-toluenesulfonamide 
• 15424-14-3 N-phenylbenzohydrazonoyl chloride 
• 105-75-9 dibutyl fumarate 
• 588-64-7 benzaldehyde phenylhydrazone 
• 52185-41-8 benzaldehyde 2-chloroformyl-2-phenylhydrazone 
• 166773-08-6 (1,3,4)-triphenyl-4,5-dihydro-1H-1,2,4-triazol-5-ylidene 
• 62256-38-6 benzaldehyde-(2,4-diphenyl semicarbazone) 
• 110-46-3 isopentyl nitrite 

Relevant academic research and scientific papers

Deoxygenation of nitrosoarene by N-heterocyclic carbene (NHC): an elusive Breslow-type intermediate bridging carbene and nitrene

N-Heterocyclic carbene (NHC) activates and deoxygenates nitrosoarene (ArNO) to afford arylnitrene (ArN), thereby portraying a fundamental route connecting two 6e?species. A combination of spectroscopic and computational studies suggests that th

Synthesis of 1,2,4-Triazol-3-imines via Selective Stepwise Cycloaddition of Nitrile Imines with Organo-cyanamides

A convenient method for the synthesis of 1,2,4-triazol-3-imines through a selective, formal, 1,3-dipolar cycloaddition of organo-cyanamide ions with nitrile imine dipoles is reported. Hydrolysis of the 1,2,4-triazol-3-imines yields the corresponding 1,2,4-triazol-5-ones. A stepwise mechanism, supported by DFT calculations, is invoked to explain the reaction selectivity.

1,4-Bis-Dipp/Mes-1,2,4-Triazolylidenes: Carbene Catalysts That Efficiently Overcome Steric Hindrance in the Redox Esterification of α- And β-Substituted α,β-Enals

As reported by Scheidt and Bode in 2005, sterically nonencumbered α,β-enals are readily converted to saturated esters in the presence of alcohols and N-heterocyclic carbene catalysts, e.g., benzimidazolylidenes or triazolylidenes. However, substituents at the α- or β-position of the α,β-enal substrate are typically not tolerated, thus severely limiting the substrate spectrum. On the basis of our earlier mechanistic studies, a set of N-Mes- or N-Dipp-substituted 1,2,4-triazolium salts were synthesized and evaluated as (pre)catalysts in the redox esterification of various α- or β-substituted enals. In particular the 1,4-bis-Mes/Dipp-1,2,4-triazolylidenes overcome the above limitations and efficiently catalyze the redox esterification of a whole series of α/β-substituted enals hitherto not amenable to NHC-catalyzed transformations. The synthetic value of 1,4-bis-Mes/Dipp-1,2,4-triazolylidenes is further demonstrated by the one-step bicyclization of 10-oxocitral to (racemic) nepetalactone in diastereomerically pure form.

Transfer hydrogenation promoted by N-heterocyclic carbene and water

N-Heterocyclic carbenes (NHCs) promote the transfer hydrogenation of various activated C=C, C=N, and N=N bonds with water as the proton source. The NHCs act as reducing reagents to be converted into their oxides. A detailed reaction mechanism is proposed on the basis of deuterium-labeling experiments.

Aldehyde umpolung by N-heterocyclic carbenes: NMR characterization of the breslow intermediate in its keto form, and a spiro-dioxolane as the resting state of the catalytic system

Surprises from a classic: The Breslow intermediate of triazolylidene- catalyzed benzoin condensations was characterized for the first time by NMR spectroscopy in its keto form (K, energetic minimum). The hitherto unknown spiro-dioxolane S, generated from

Chemical reactions of the stable carbene 1,3,4-triphenyl-4,5-dihydro-1H-1,2,4-triazol-5-ylidene

The title compound 1,3,4-triphenyl-4,5-dihydro-1H-1,2,4-triazol-5-ylidene (1), a stable carbene, is chemically characterized via its reactivity towards a multitude of organic substrates. Its behaviour in insertion, addition and cycloaddition reactions allows its classification as a typical representative of nucleophilic carbenes. VCH Verlagsgesellschaft mbH, 1996.

Darstellung, Struktur und Reaktivitaet von 1,3,4-Triphenyl-4,5-dihydro-1H-1,2,4-triazol-5-yliden, einem neuen stabilen Carben

Stichworte: Carbene * Cycloadditionen * Heterocyclen * Insertionen

Reactions of Sulfur Monochloride with some Aromatic Aldehyde Semicarbazones and Thiosemicarbazones: New Syntheses of Substituted 2,4-Dihydro-1,2,4-triazol-3-ones, 2,4-Dihydro-1,2,4-triazole-3-thiones and 2-Amino-1,3,4-oxadiazoles

Treatment of various substituted semicarbazones of aromatic aldehydes with sulfur monochloride yields the corresponding substituted 2,4-dihydro-1,2,4-triazol-3-ones.With thiosemicarbazones, the products are derivatives either of the 2-amino-1,3,4-thiadiaz

Oxidation of Aldehyde Semicarbazones with Lead Dioxide: Application to the Syntheses of 2-Amino-1,3,4-oxadiazoles and 2,4-Dihydro-1,2,4-triazol-3-ones

The oxidation of aldehyde semicarbazones with lead dioxide in acid media was effected.The 4,4-disubstituted semicarbazones of aromatic aldehydes afford 2-amino-1,3,4-oxadiazole derivatives.The 2,4-disubstituted semicarbazones give 2,4-dihydro-1,2,4-triazo