Yu. N. Tkachenko

5-Diazouracils in azo coupling reactions

Abstract6-Hydroxy-5-diazo-6H-uracil and 6-hydroxy-5-diazo-1,3-dimethyl-6H-uracil enter into azo coupling reaction with CH-acids, active phenols, arylamines, and heterocycles. The conditions of reaction depend on the substrate character.

Pyrrolopyrimidines. 1. Electrophilic substitution reactions of 1,3-dimethylpyrrolo[3,2-d]pyrimidine-2,4-dione

The reactions of halogenation, aminomethylation, acylation, and azo coupling in 1,3-dimethylpyrrolo[3,2-d]pyrimidine-2,4 dione proced at position 7, whereas nitration in acetic acid is directed primarily to position 6. In a num of cases, products of substitution of both hydrogen atoms in the pyrrole ring have been synthesized.

Synthesis, structure, and properties of phosphorus-containing bis(amidrazones)

Previously unknown ethenylphosphonic derivatives of bis(amidrazones) were prepared. According to spectroscopic data and quantum-chemical calculations, these compounds exist as phosphonium salts of a symmetrical linear structure with trans arrangement of the amidrazone fragments. In alkaline solutions, they are unstable and decompose to form triarylphosphine oxides. In contrast to ordinary amidrazones, their phosphorus-containing derivatives do not tend to form complexes with transition metals.

Protolytic and complexation properties of the cyclic thiosemicarbazone ligand

The acid-base properties of the thiourea based cyclic thiosemicarbazone have been studied. The tautomerism and complex formation ability of the thiosemicarbazone were investigated by the methods of quantum chemistry and electronic spectroscopy. The complexes of copper(II), nickel(II), cobalt(II), and mercury(II) were synthesized and their structure suggested.

Synthesis, structure, and properties of a new phosphorus-containing Schiff’s base, a derivative of pyrazole-5-one

A new Schiff’s base and its salt have been prepared from 2-aminophenyl(triphenyl)phosphonium chloride and 5-hydroxy-3-methyl-1-phenyl-4-formylpyrazole. The products structures have been proved by IR, 1H NMR, and UV spectroscopy, mass spectrometry, X-ray diffraction analysis, and quantum-chemical modeling. Possible tautomerism and some properties of the products have been studied.

Pyrrolopyrimidines. 4. A convenient method for the production of 6-(2-aminovinyl)-5-nitropyrimidines and their transformation into pyrrolo[3,2-d]pyrimidines

A convenient method is proposed for the production of 6-(2-aminovinyl)pyrimidine-2,4-diones, involving the reaction of 6-methyluracils with triethyl orthoformiate and secondary amines.

Pyrano[4,3-d]pyrimidinium salts: 1. Reactions with N-nucleophiles

Abstract5-Aroyl-1,3,6-trimethyluracils were converted to pyrano[4,3-d]pyrimidinium salts. Reactions of the salts obtained with ammonia, primary amines, and hydrazine were studied.

3,4-DIACETYLHEXANE-2,5-DIONE : AN EFFECTIVE SYNTHON FOR SYNTHESIS OF SUBSTITUTED AZULENE HETEROANALOGS BY CYCLOCONDENSATION REACTIONS

The one-pot method for the synthesis of 4,8-dialkoxy-6-aryl-1,3-dimethylcyclohepta [c]furanium perchlorates has been developed. The method is based on the cyclocondensation of 3,4-diacetylhexane-2,5-diones with aromatic aldehydes and trialkyl orthoformates under the action of a 16% perchloric acid solution in acetic anhydride. Under similar conditions, with hydrogen sulfide, cyclohepta[c]thiophenium perchlorates have been obtained, while cyclohepta[c]pyrrolium perchlorates have been prepared with arylamines, ammonium acetate, or aliphatic amine acetates. A heteroanalog of azulene, 4,8-diethoxy-1,3-dimethyl-2-azaazulene, has been obtained for the first time. Hydrolysis of aza- and thiaazulenium salts gives the corresponding cyclohepta[c]pyrrol-4-ones and cyclohepta [c]thiophen-4-ones.

Synthesis, Structure, and Properties of New Phosphorus Schiff Bases

A series of new Schiff bases has been synthesized on the basis of (2-aminophenyl)triphenyl-phosphonium chloride and substituted salicylaldehydes. The structure of the prepared compounds has been established by means of IR, UV, and 1H NMR spectroscopy, as well as DFT B3LYP/6-31G(d,p) quantum-chemical simulation. The possible tautomerism and certain properties of the azomethines, including complex formation, have been studied.

Pyrrolopyrimidines. 3. 5-Amino-1,3-dimethylpyrrolo-[3,2-d]pyrimidine-2,4-dione

Reaction of 5-amino-1,3-dimethylpyrrolo[3,2-d]pyrimidine-2,4-(1H,3H)-diones with β-diketones produces enaminoketones. Some of these are converted by Lewis acids into pyrrolopyridazines.