Synthesis of the ethyl ester of the mononitrile of malonic acid by the catalytic carbonylation of benzenesulfonyloxyacetonitrile

A new method has been developed for the synthesis of the ethyl ester of the mononitrile of malonic acid by the carbonylation of benzenesulfonyloxyacetonitrile in absolute ethanol in the presence of cobalt carbonyl. The yield of the desired product was 30% with 60–90% conversion of the starting compound. The effects of temperature, pressure, and reaction time were studied.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. S. M. Kirov Urals Polytechnical Institute, Ekaterinburg. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 215–216, January, 1992.     

Formation of n-α-diazoacetylureas by the reaction of derivatives of 5-hydroxy-1,2,3-triazole-4-carboxamide with phenylisocyanate and phenyl isothiocyanate

The reaction of derivatives of 5-hydroxy-1,2,3-triazole-4-carboxamide with phenyl isocyanate and phenyl isothiocyanate proceeds at the 4-carboxamide fragment of the first, leading to the formation of derivatives of N-phenyl-N-(2-diazo-2-carbamoylacetyl)urea and -thiourea correspondingly.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1347–1350, October, 1992.     

A catalyst-free one-step synthesis of N-pyrimidinyl amidines from endocyclic enamines and 4-azidopyrimidines

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Heterocyclization of compounds containing diazo and cyano groups. 4. Reactions of 2-diazo-2-cyanoacetic acid amides with P4S10 and the lawesson reagent. Synthesis and recyclization of 5-amino-1,2,3-thiadiazole-4-carbothioamides

5-Amino-1,2,3-thiadiazole-4-carbothioamides were obtained in the reaction of carbonyl derivatives of diazoacetonitrile with P₄S₁₀ and the Lawesson reagent. A novel recyclization of 1,2,3-thiadiazole-4-carbothioamides was observed.See [1] for Communication 3.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 845–849, June, 1987.     

Synthesis of mesoionic[1,2,3]triazolo[5,1-d][1,2,5]triazepines

Intramolecular cyclization of 1-amino-3-phenacyl-4-carbohydrazido-1,2,3-triazolium-5-olates has been shown to take place via selective interaction of the carbonyl group with the terminal amino function of the hydrazido group to form a 1,2,5-triazepine ring. Minor products, resulting from the interaction of the α-nitrogen atom of the hydrazido group with the carbonyl function, having a N-amino-pyridazine structure were also detected and isolated. A general method for the synthesis of novel mesoionic 2-amino-7-aryl-4-oxo-2,4,5,8-tetrahydro[1,2,3]triazolo[5,1-d][1,2,5]triazepin-9-ium-3-olates was developed.     

Pericyclic and Heteroelectrocyclic Mechanisms for the Cyclization of 1,3,5-Hexatrien-1-one and Its 6-Aza Analog

The cyclization of 1,3,5-hexatrien-1-one, 1, and the Z- and E-isomers of 1-aza-1,3-butadienylketene 3 were studied using the semiempirical AM1 and PM3 methods. Cyclizations of compounds 1 and Z-3 are shown to occur via a mono-rotation mechanism with barriers of 15.49 and 32.85 kcal/mol respectively. The reactions proceed via non-planar transition states which result from rotation of the methylene group for compound 1 and the imino group for compound Z-3. Cyclization of E-3 proceeds via a non-rotatory mechanism through a planar transition state. The activation barrier is 4.83 kcal/mol (AM1). The electronic structures of the initial and final states, and of some intermediate structures, including the transition states for the cyclization of compounds 1 and 3, were analyzed by the natural orbital method using HF/6-31G*//AM1 calculations. Energetic, structural, and orbital criteria indicate the heteroelectric mechanism for the cyclization of compound E-3 and the pericyclic mechanism for the cyclization of compounds 1 and Z-3.     

Reactions of 5-dialkylamino-1,2,3-thiadiazole-4-carbaldehydes with amines as a method for the synthesis of 1,2,3-triazole-4-carbothioamides

A method for the synthesis of previously inaccessible 5-dialkylamino-substituted 1,2,3-thiadiazole-4-carbaldehydes was developed. Ring transformation in these compounds induced by primary aliphatic and aromatic amines, hydroxylamines, and N-substituted hydrazines resulted in the synthesis of a broad range of 1,2,3-triazole-4-carbothioamide.     

The regioselectivity of the formation of 2-pyrazolylthiazoles and their precursors from the reaction of 2-hydrazinothiazoles with 4,4,4-trifluoro-1-hetaryl-1,3-butanediones

Reaction of 2-hydrazinothiazoles 1 with 1-thienyl- and 1-furyl-1,3-butanediones 2a,b in methanol in the presence of hydrochloric acid mainly leads to a mixture of pyrazoles 3 and pyrazolines 4 or pyrazoles 3 and 5 in strong acidic conditions. Isomeric hydrazones 6 and pyrazolines 4 were formed and isolated in these reactions in the absence of hydrochloric acid. It has been shown that the regioselectivity in the reaction of diketones 2 with hydrazine 1 is governed by both the concentration of acid and the nature of substituents in the 1,3-diketones 2. Cyclization of hydrazones 6 is shown to occur under milder conditions than dehydration for pyrazolines 4. The new heterocyclic compounds were prepared and fully characterized by NMR spectra and by X-ray analysis for 3c.