Svetlana V. Shishkina

Condensed Isoquinolines. 15. Synthesis of 5,10-Dihydro[1,2,4]triazolo[1,5-b]isoquinolines and Related Spiranes

Condensation of o-bromomethylphenylacetonitrile with arylcarbohydrazides gave, depending on the reaction conditions, 2-arylcarboxamido-1,4-dihydroisoquinoline-3(2H)-imine hydrobromides or 2-aryl-5,10-dihydro[1,2,4]triazolo[1,5-b]isoquinolines. Analogous condensation of 4-(2-bromomethylphenyl)tetrahydro-2H-pyran-4-carbonitrile and 1-(2-bromomethylphenyl)-1-cyclopentanecarbonitrile with arylcarbohydrazides gave respectively 2-aryl-2,3,5,6-tetrahydrospiro[4H-pyran-4,10(5H)-[1,2,4]triazolo[1,5-b]isoquinolines and 2-arylspiro[1,2,4]triazolo[1,5,b]isoquinoline-10(5H)-1-cyclopentanes, derivatives of new spirane heterocycles. The reaction with condensing agents of 3-imino-2,2,3,35,6-hexahydrospiro[isoquinoline-4(1H),4-4H-pyran]-2-amine and 3-imino-2,3-dihydrospiro[isoquinoline-4(1H),1-cyclopentane]-2-amine hydrobromides, synthesized from the corresponding bromo nitriles and hydrazine, may serve as an alternative route for the synthesis of these compounds. The structure of obtained triazoloisoquinolines was established from IR, 1H and 13C NMR spectra. An X-ray crystallographic study of 2-phenylspiro[1,2,4]triazolo[1,5-b]isoquinoline-10(5H),1-cyclopentane was carried out.

4-hydroxy-2-quinolones. 118*. Synthesis, structure, and chemical properties of 2-bromomethyl-5-oxo-1,2-dihydro-5H-oxazolo-[3,2-a]quinoline-4-carboxylic acid and its ethyl ester

Bromination of N-allyl-substituted 4-hydroxy-2-quinolinones with molecular bromine in acetic acid or carbon tetrachloride occurs with closing of a five membered oxazole ring to give 2-bromomethyl-5-oxo-1,2-dihydro-5H-oxazolo[3,2-a]quinoline.

Intermolecular interactions in polymorphs of the cyclic trimeric perfluoro-ortho-phenylene mercury from geometric, energetic and AIM viewpoints: DFT study and Hirshfeld surface analysis

Macrocyclic polydentate Lewis acids are of ongoing interest owing to their ability for molecular recognition of anions; however, deep understanding of the nature of supramolecular bonding in their crystals is still lacking. To solve this problem, we have analysed four polymorphic modifications A–D of cyclic trimeric perfluoro-ortho-phenylene mercury (1) by quantum chemical calculations of intermolecular pair interactions energy. In all polymorphs, the main structural motif is stacked columns, which are further connected to a three-dimensional structure with either ladder-shape interactions between parallel macrocycles or T-shape interactions between nearly perpendicular macrocycles. Both arrangements contribute almost equally to the stabilization of the crystal structure. According to DFT computational study of isolated dimers that correspond to the most energetically favourable molecular pairs, and topological analysis of electron density distribution, the stabilization of these dimers is governed by Hg···C and C···C interactions. Significant contribution also comes from F···C and Hg···F interactions, while the role of mercurophilic interactions and F···F contacts seems negligible. Statistical analysis of crystal structures of host–guest complexes of the macrocycle 1 using Voronoi polyhedra and Hirshfeld surfaces showed the same types of intermolecular interactions to be responsible for stabilization of its polymorphs and co-crystals.

Reactions of α-aminoazoles with diethyl benzylidenemalonate

Cyclocondensations of diethyl benzylidenemalonate with 3-amino-5-methylpyrazole, 3,5-diamino-1,2,4-triazole, 3,4,5-triamino-1,2,4-triazole, and 2-amino-benzimidazole in alcohols take a single route and lead to the formation of functionally substituted partially hydrogenated pyrazolo-, triazolo[1,5-a]-pyrimidin-5-ones and pyrimido[1,2-a]benzimidazol-2-one respectively. From reaction mixtures involving 3-amino-1,2,4-triazole and its 5-methylsulfanyl analog in methanol the intermediate products of heterocyclization were isolated forming as a result of alkylation with the β-carbon of the unsaturated ester the endocyclic nucleophilic sites of aminoazoles. The structure of one among the products obtained, diethyl(3-amino-5-methylsulfanyl-1,2,4-triazol-2-yl)benzylmalonate was proved by X-ray crystallography. In DMF the same reagents yielded mixtures of partially hydrogenated triazolo[1,5-a]pyrimidin-5-ones.

Synthesis of 1,6-diamino-2-imino-2,3-dihydropyrimidin-4(1Н)-one and preliminary study of its two- and three-component reactions

n A new heterocyclic compound, 1,6-diamino-2-imino-2,3-dihydropyrimidin-4(1H)-one, was synthesized for the first time and some of its chemical properties were studied. This pyrimidinone showed very unusual reactivity comparing to analogous compounds in reactions with alkylating and acylating agents and in other two-component reactions. Three-component reactions involving 1,6-diamino-2-imino-2,3-dihydropyrimidin-4(1H)-one were also explored.

New carbacylamidophosphates (CAPh) and CAPh-containing coordination compounds: structural peculiarities

The new carbacylamidophosphate derivative HL1xa0(1) with general formula Cl3CC(O)N(H)P(O)(CH2C5H4N)2 named 2,2,2-trichloro-N-(3-(aminomethyl)pyridine)-1-yl-phosphoryl)-acetamide), the potassium, lanthanide and uranylxa0(VI) complexes with the different CAPh ligands: KL2·H2Oxa0(2) and Eu(L2)3·H2Oxa0(3) with 2,2,2-trichloro-N-(dimorpholinophosphoryl)acetamide (CCl3C(O)N(H)P(O)(N(C2H4)2O)2, HL2), Ce(L3)3(i-PrOH)2·i-PrOHxa0(4) with N-(bis(phenylamino)phosphoryl)-2,2,2-trichloroacetamide (CCl3C(O)N(H)P(O)(NHC6H5)2, HL3), Nd(NO3)3(HL4)2 (5), Nd(NO3)3(HL5)2 (6) and UO2(NO3)2(HL5)2 (7) (HL4=CH3(C4H3N)C(O)N(H)P(O)(N(CH3)2)2 –N-(bis(dimethylamino)phosphoryl)-1-methyl-1H-pyrrole-2-carboxamide, HL5=CH3(C4H3N)C(O)N(H)P(O)(N(C2H5)2)2—N-(bis(diethylamino)phosphoryl)-1-methyl-1H-pyrrole-2-carboxamide) have been synthesized. Obtained compounds were characterized by means of FTIR, 1H and 31P NMR spectroscopy. Crystal structures of 1–7 have been determined. Compound 2 represents the first structure of the deprotonated CAPh compounds with bridging function of both carbonyl and phosphoryl groups. Structural peculiarities of CAPh ligands in the composition of the synthesized coordination compounds are discussed.

Reactions of α-aminoazoles with (2E)-3-phenylacryloyl chloride

Reaction of 5-amino-3-methylpyrazole, 3-amino-, 5-amino-3-methylsulfanyl-1,2,4-triazole and 5-amino-1,2,4-triazole-3-thione with 3-phenylacryloyl-chloride under mild conditions is characterized by low selectivity and does not lead to the formation of fused heterocyclic systems but gives mixtures of products of mono- and diacylation of the nucleophilic sites in the molecules of α-aminoazoles. Endocyclic monoacyl derivatives of aminotriazoles in DMF undergo a transacylation at the exo-amino-group followed by cyclization into dihydro-1,2,4-triazolo[1,5-a]-pyrimidin-5-ones.

4-Hydroxy-2-quinolones 123. Amidation of 2-bromomethyl-5-oxo-1,2-dihydro-5H-oxazolo[3,2-a]-quinoline-4-carboxylic acid

The reaction of 2-bromomethyl-5-oxo-1,2-dihydro-5H-oxazolo[3,2-a]quinoline-4-carboxylic acid with thionyl chloride is accompanied by a transformation of the oxazoloquinolone ring to give 4-chloro-1-(2,3-dichloropropyl)-2-oxo-1,2-dihydroquinoline-3-carboxylic acid chloride.

4-Hydroxy-2-quinolones 127. Simple method for exchanging chlorine for hydroxyl in 1-R-4-chloro-3-ethoxycarbonyl-2-oxo-1,2-dihydroquinolines

Treatment of ethyl 1-R-4-chloro-2-oxo-1,2-dihydroquinoline-3-carboxylates with sodium nitrite in DMSO is a convenient method for their conversion to the corresponding 4-hydroxy derivatives.

4-Hydroxy-2-quinolones 119. Reaction of ethyl 1-R-4-chloro-2-oxo-1,2-dihydroquinoline-3-carboxylate with malononitrile

In acid medium ethyl 1-R-4-dicyanomethyl-2-oxo-1,2-dihydroquinoline-3-carboxylates are hydrated in the ketenimine tautomer form exclusively to the corresponding quinolylcyanoacetamides.