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Upstream product

• 137609-50-8 benzaldehyde 2-methyl-4-phenylthiosemicarbazone 
• 21076-09-5 2-methyl-4-phenyl-3-thiosemicarbazide 
• 1663-61-2 triethoxymethylbenzene 

Relevant academic research and scientific papers

Photocyclization reaction of some 2-methyl-4-phenyl- substituted aldehyde thiosemicarbazones. Mechanistic aspects

Irradiation of 2-methyl-4-phenyl- substituted benzaldehyde thiosemicarbazones led with good yields to the corresponding ?21,2,4- triazoline-5-thione derivatives through the formation of stable 1,2,4- triazolidine-5-thione intermediates. The relative quantum yields of photocyclization at 313 nm were analysed by means of the Hammett equation and p values determined: We interpreted the results in terms of the mechanism of photocyclization of 2-methyl-4-phenyl-substituted benzaldehyde thiosemicarbazones. (C) 2000 Elsevier Science Ltd.

A Study of the Behaviour of 2,4-Substituted Thiosemicarbazides toward Orthoesters: Formation of Mesoionic Compounds

The reactions beetwen 2,4-disubstituted thiosemicarbazides and orthoesters in refluxing xylene led to the formation of the 1,2,4-triazoline-5-thione ring and to the 1,2,4-triazolium-5-thiolate ring. The formation of the mesoionic componds is due to rearrangement of the easily available 2,4-disubstituted thiosemicarbazides to 1,4-disubstituted thiosemicarbazides under the reaction conditions adopted. This method can be usefully used for the synthesis of mesoionic compounds, especially in the case of the 2-methyl-4-phenylthiosemicarbazide.

Unexpected Substituent Effects on the Rate of the Oxidative Cyclization of 2-Methyl-Substituted Aldehyde Thiosemicarbazones Induced by Cupric Perchlorate

As a development of our previous work, we performed a kinetic study of the oxidative cyclization of some 2-methyl-substituted aldehyde thiosemicarbazones induced by cupric perchlorate hexahydrate in methanol at 298 K.Differently from the oxidation with anhydrous ferric chloride - which leads to the formation of both the 1,2,4-triazoline-5-thione and 5-imino-Δ2-1,3,4-thiadiazoline rings - the only reaction products are the triazolines.Data illustrated herein allow us to have a reasonable picture of the reaction mechanism.

A quantitative study of substituent effects on oxidative cyclization of some 2-methylsubstituted aldehydes. Thiosemicarbazones induced by ferric chloride

In order to gain further mechanistical information about the cyclization of thiosemicarbazones and thiosemicarbazone-type substrates induced by metallic salts as oxidizing agents, we performed the synthesis of substrates 1a-s and a kinetic study of the oxidative cyclization of 1 to 5-imino-Δ2-1,3,4-thiadiazole 2 and 1,2,4-triazoline-5-thione 3 derivatives induced by methanolic ferric chloride solutions. The results of cyclization were compared to those of corresponding semicarbazones. The kinetic data were analyzed by means of the Hammett's equation and p values discussed.

Photochemical Cyclization of Some Aldehyde Thiosemicarbazones

The photochemical behaviour of some substituted aldehyde thiosemicarbazones 1a-k has been investigated in methanol at 254 nm.Thiosemicarbazones of glyoxil methyl ester 1a-f cyclized to furnish the 3-thioxo-1,2,4-triazin-5-one 2-ring system.The remaining thiosemicarbazones 1g-j gave 1,2,4-triazoline 4-derivatives.

Substituent Effect on Oxidative Cyclization of Aldehyde Thiosemicarbazones with Ferric Chloride

The reactivity of aldehyde thiosemicarbazones 1 with ferric chloride solutions was examined.When compounds 1 are not substituted on the N-2 nitrogen atom formation of 1,3,4-thiadiazole 3 heterocyclic ring was observed.In contrast 1,2,4-triazoline 4 and/or