G. V. Gridunova

Synthesis and x-ray study of triferrocenyliodidephosphonium triiodide

Abstract A series of iodine derivatives of ferrocenylphosphorus compounds has been obtained. An X-ray investigation of [Fc 3 PI] + I 3 − has been carried out. All ferrocenyl fragments posses close geometric parameters, similar to those of ferrocene and its derivatives. The positive charge of the cation is localized on the phosphorus atom. Symmetrical I 3 − anions of linear configuration form zigzag-shaped chains, as is usual for triiodides. The cation—anion interaction is realized through short I…I contacts.

Synthesis of 4,7-diamino-3-formylcoumarins and azomethines derived from them

A series of 4,7-diamino-3-formylcoumarins has been synthesized by the reaction of 7-dialkylamino-4-chloro-3-formylcoumarins with primary and secondary amines and by the formylation of 4,7-diaminocoumarins by the Vilsmeier reaction. The corresponding Schiffs bases are formed by reaction with primary amines.

X-ray structural and spectral study of 1:2 solvate of 2,7-dinitro-4-bromo-10,10-dihydroxyphenanthren-9-one with dimethylformamide

An x-ray structural study showed the total similarity of the behavior of 2,4,7-trinitro- and 2,7-dinitro-4-bromo-9,10-phenanthrenequinones dissolved in aqueous DMF: addition of a molecule of water at one of the two carbonyl groups with formation of the corresponding 10,10-dihydroxyphenanthren-9-ones takes place in both cases in soft conditions. These products of hydration exist as hydrogen-bonded solvates with molecules of the solvent whose crystals are isostructural to each other. The results of the x-ray structural study are in agreement with the data from the IR absorption and electron absorption spectra; their comparison suggests the existence of equilibrium between the starting compounds and the products of hydration, and the equilibrium position is a function of the polarity of the basic solvent.

Crystal and molecular structure of the benzene solvate of 2,4,7-trinitro-9,10-phenanthrenequinone

ConclusionsAn x-ray diffraction structural analysis established the molecular and crystal structure of the benzene solvate of 2,4,7-trinitro-9,10-phenanthrenequinone. The bond length distribution in this trinitrophenanthrenequinone indicates π-electron localization at the periphery of the phenanthrenequinone system, whose significant distortion is due to steric and electronic factors.

Condensed heterocycles Communication 43. Synthesis and transformations of benzo[b]selenopheno[3,2-d]-1,2,3-selenadiazoles and benzo[b]selenopheno[3,2-d]-l,2,3-thiadiazoles and a study of the molecular and crystal structure of dibenzo[b]selenopheno-[2,3-b;2,3-e]-1,4-diselenine

Conclusions1.Methods were developed for the synthesis of benzo[b]selenopheno[3,2-d]-1,2,3-thiadiazole and benzo[b]selenopheno[3,2-d]selenadiazole based on the reaction of the semicarbazone of 3-oxo-2,3-dihydrobenzo[b]selenophene with SOCl2 or SeO2, respectively.2.The reaction of the selenadiazole with alcoholic alkali or the thermal decomposition of this compound gave dibenzo[2,3-b;2,3-e]-1,4-diselenine.3.The major fragmentation processes of the M+. ions of the thiadiazoles and selenadiazoles upon electron impact is the consecutive loss of N2 and CS or CSe molecules, while in the case of the diselenine, the major process is the elimination of the heteroatoms.4.A study was carried out on the crystal and molecular structure of dibenzo[b]selenopheno[2,3-g;2,3-e]-1,4-diselenine which revealed that this compound has trans configuration and twist boat conformation of the central heterocycle.

X-RAY DIFFRACTION AND SPECTRAL STUDY OF PRODUCTS OF REACTION BETWEEN 2,7-DINITRO AND 2,4,7-TRINITROPHENANTHRENEQUINONE AND NITROMETHANE

The molecular and crystalline structures of three products of the reaction between 2,7-dinitro- and 2,4,7-trinitrophenanthrenequinone with nitromethane in an HMPTA solution were studied by x-ray diffraction. Two of these products are H-bonded 1:1 solvates.

The ethynyl carbocation. 4. Reaction of 4-phenylethynylpyrylium salts with c-nucleophiles

The reaction of 4-phenylethynylpyrilium salts with indoles leads to indolylvinylpyrilium derivatives through attack of the β-carbon atom of the triple bond and subsequent intramolecular transfer of a proton from C(in3) of the indole ring to the sp-hybridized carbon atom of the allene group. The structure of 2,6-diphenyl-4-[2′-phenyl-2′-((β-methylindolyl)vinyl]pyriliumperchloratewasdeterminedunequivocallybyx-ray diffraction analysis and the most likely reaction scheme was indicated. The bond length distribution in the pyrilium cation indicates significant delocalization of positive charge.

Crystal and molecular structure of the solvate of 2,4,7-trinitro-9,9,10,10-tetrahydroxyphenanthrene with hexamethylphosphortriamide (I) and the solvate of 2,4,7-trinitro-10,10-dihydroxyphenanthren-9-one with dimethylformamide (II)

Two products of the addition reactions of H2O at the carbonyl bonds of 2,4,7-trinitro-9,10-phenanthrenequinone, formed under mild conditions when it is dissolved in aqueous hexamethylphosphortriamide (HMPTA) and dimethylformamide (DMF), have been studied by x-ray diffraction. The crystalline solvates of 2,4,7-trinitro-9,9,10,10-tetrahydroxyphenanthrene (C14H9N3O10·3HMPTA) and 2,4,7-trinitro-10,10-dihydroxyphenanthren-9-one (C14H7N3O9·2DMF) are formed. In the first of these, all the molecules of the included solvent are disordered in complex fashion. Both crystal structures are stabilized by strong hydrogen bonds between the solvated and solvating molecules.

Structure of 2,4-diamino-6-(2,4-diphenyl-1-cyano-1,3-butadien-1-yl)-5-cyano-nicotinonitrile

An x-ray diffraction structural analysis was carried out to determine the structure of the 1∶2 solvate of 2,4-diamino-6-(2,4-diphenyl-1-cyano-1,3-butadien-1-yl)-5-cyano-nicotinonitrile with acetonitrile (I) using λMo radiation to R=0.043. The unit cell parameters of the monoclinic crystals of I are as follows: a=11.019, b=23.541, c=9.861 Å, β=105.45°, dcalc=1.27, Z=4, space group P21/c. The nonplanar, sterically strained molecule has trans configuration with E arrangement of the substituents in the butadiene fragment. The molecular packing in the crystal solvate is determined by the hydrogen bonding between the amino and cyano groups and coulombic interactions due to the polar nature of the acetonitrile molecules. The effect of the substituents on the pyridine ring geometry, analogous to that reported for benzene derivatives, is discussed.

Molecular structure of N-mesityl-6H-anthra[9,1-bc]pyrrol-6-one

The molecular and crystalline structure of 1-(2,4,6-trimethylphenyl)-6H-anthra-[9,1-bc]pyrrol-6-one was determined by the x-ray structural method. There is a larger uniformity of the bonds in the benzene ring of the isoindole fragment than in the N-substituted isoindoles; this derives from the electronic influence of the keto group. The structure of the whole molecule does not have marked 1,10-anthraquinoid character.