Novel heterocyclization of 4-phenylthiosemicarbazones and related compounds with chlorocarbonylsulfenyl chloride

Synthesis of Novel 1,3-thiazole-, 1,2,4-triazole- thione and Triazepine Derivatives

Reaction of the cyanoacetic hydrazide derivatives 1a–e with isothiocyanates gave the hydrazinocarboxamide and thioamide derivatives 2a–g and 1,2,4-triazole-3-thiones 3. Upon reacting 1b–d with ethyl bromoacetate followed by isothiocyanates; the 1,3-thiazole-5-carbohydrazides 5 were afforded. Cyclisation of products 1b–e with triethylorthoformate furnished the unexpected ethyl cyanoacetylhydrazonoformate 6; rather than the expected triazolethiones of type 7. A mechanism for the formation of product 6 was suggested and discussed. Upon heating product 6 with some arylamines in acetonitrile, the 5-aminotriazepin-7-ones 9 were afforded.

Four-coordinated see-sawN-(aryl)-2-(propan-2-ylidene)hydrazinecarbothioamide complexes of nickel(ii), copper(ii) and zinc(ii) and their propensity for catalytic cyclisation

Four-coordinated metal complexes of two hydrazinecarbothioamide-derived ligands with divalent nickel, copper and zinc are described and the selective reactivity difference of copper(ii) to cyclise the ligand or to form a complex is described.

5-Ethyl-5-methyl-4-phenyl-5H-1,2,4-triazol-3(4H)-thione

The five-membered ring of the title compound Δ¹-1,2,4-triazoline-5-thione, C₁₁H₁₃N₃S, is almost planar (r.m.s. deviation = 0.009 Å); the phenyl ring is aligned at 84.6 (2)° with respect to the five-membered ring. The crystal studied was a racemic twin with an approximate 20% minor twin component. Weak inter­molecular C—H⋯N hydrogen bonding is present in the crystal structure.