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A unique Ni-catalyzed transformation is reported for the one-pot highly selective synthesis of previously unknown monoseleno-substituted 1,3-dienes starting from easily available terminal alkynes and benzeneselenol. The combination of a readily available catalyst precursor, Ni(acac)2, and an appropriately tuned phosphine ligand, PPh2Cy, resulted in the exclusive assembly of the s-gauche diene skeleton via the selective formation of C–C and C–Se bonds. The unusual diene products were stable under regular experimental conditions, and the products maintained the s-gauche geometry both in the solid state and in solution, as confirmed by X-ray analysis and NMR spectroscopy. Thorough mechanistic studies using ESI-MS revealed the key Ni-containing species involved in the reaction.

Hexasubstituted derivative of cyclotriphosphazene containing hydroxyaryloxy moieties was obtained from bisphenol A using allyl protection of phenolic groups.

An efficient catalytic system based on easily available palladium acetate was developed for the selective addition of aliphatic thiols to the triple bond of internal alkynes. Formed in situ [M(SR)2]n nanostructured particles were found to be an active form of the catalyst. It was experimentally confirmed for the first time that the most active form of the catalyst for thiol addition to internal alkynes is formed only in the reaction mixture containing the both reactants, namely, alkyne and thiol.

The interaction of 3-nitro- and 3,6-dinitro-4-(2-hydroxy-4,5-R 2 -phenoxy)-2H-1-benzopyran-2-ones 4a–d with triethylamine leads to the formation of triethylammonium salts of corresponding anionic spirocyclic compounds 5a–d as a result of intramolecular nucleophilic attack of aroxide-ion on position 4 of the benzopyran system. The structure are proved by 1 H NMR, IR spectroscopy and X-ray analysis of 5c . The distribution of electron density in the model anion M was calculated from X-ray data.

MNDO/PM3 calculations have proved the possibility of the existence in mBr2 nAlBr3 systems of highly electrophilic complexes with bidentate coordination of AlB r 4 - anions with a positively charged (up to + 1.45 a.u.) Br atom.

Molecular and electronic structure of heterofullerene BNC58 (C s) and B2N2C56 (C 2h) monomers, B2N2C116 and B4N4C112 dimers, and B6N6C168 trimer (the last three molecules withC 2h symmetry) was simulated by the MNDO method. Clusters BNC58 and B2N2C56 are formed by replacement of carbon atoms participating in one or two of the most distant oppositely lying (6,6)-type C−C bonds in fullerene C60 by B and N atoms. In one of the two studied isomers of the B2N2C116 dimer, the monomers are linked by the four-membered carbon cycle, while the heteroatoms form the most distant oppositely lying bonds of the dimer. In the other isomer of the B2N2C116 dimer, as well as in the B4N4C112 dimer and B6N6C168 trimer, the monomers are linked by four-membered B2N2 cycles with alternation of the atoms. For all the systems studied, the optimum geometric parameters, heats of formation, ionization potentials, and atomic charges were calculated. Dimerization energies of heterofullerenes BNC58 and B2N2C56 lie in the range from 33 to 49 kcal mol−1. It was found that the B2N2C116 dimer, in which the monomers are linked by the four-mernbered carbon cycle, is the most stable system. In the case of B2N2C56 trimerization, the energy gain (compared to the triple monomer energy) is about twice as large as the dimerization energy. Molecular structure of the quasi-linear [B2N2C56) n macromolecule was simulated, and extended Huckel calculations of its energy band structure by the crystal orbital method were performed. It was found that the electron energy spectrum is of semiconducting type (the band gap is equal to 1.27 eV.

The addition of photochemically generated phosphoryl radicals [˙P(O)(OPri)2] to [76]fullerene has been studied by EPR and seven out of the nineteen possible RC76˙ regioisomers are obtained, six of which are stable. This compares with the previously observed addition of phosphoryl radicals to [70]fullerene which afforded three of the five expected RC70˙ regioisomers (only one being stable). Semi-empirical MNDO/PM3 calculations of the energies of all nineteen HC76˙ models and the unpaired electron distributions within them, were carried out in order to aid the assignment of the observed spectra to specific P(O)(OPri)2C76˙ regioisomers.

The ability of cyclopentadienyl type derivatives of corannulene C20H10 and fullereneIh-C60 to form η5-π-complexes and the problem of their existence is discussed. MNDO/PM3 calculations of half-sandwich complexes η5-π-MC20H15, η5-π-MC20H15+, η5-π-MC60H5, η5-π-MC60H5 and sandwich complexes 2η5-π-M(C20H15)2, 2η5-π-M(C20H15)2, 2η5-π-M(C60H5)2 (M=Si, Ge, Sn, Pb) were performed. For all systems studied, local minima were found on corresponding potential energy surfaces and the heats of formation, geometric parameters, and distributions of effective atomic charges were calculated. Sandwich complexes are most likely to exist with M=Si and Ge. The energy and geometric characteristics of η5-π-complexes of corannulene were compared with those of η5-π-complexes of fullereneIh-C60. It was concluded that the results of quantum-chemical calculations of sandwich type corannulene derivatives can be used for simulation of the geometry and electronic structure of analogous complexes of fullereneIh-C60.

The problem of existence of η3—π-complexes of C60 fullerene with transition metal atoms is discussed. The complexes C60R3Co(CO)3 (R = H, F, Cl, Br), C60H3NiCp, and C60H3Fe(CO)Cp, where C60R3 is an allyl derivative of C60 fullerene, were shown to be sufficiently stable. In these complexes the metal atoms are η3—π-bound to the fullerene cage. In contrast to this, the metal atoms in the C60H3Li and C60H3FeCp complexes are η5—π-coordinated to the carbon cage. Density functional calculations were carried out with the Perdew—Burke—Ernzerhof exchange-correlation potential (PBE). It was concluded that the type of bonding in the complexes of allyl derivatives of C60 fullerene depends on the nature of the species attached. Among the systems studied, the maximum energy of the η3—π-bond was obtained for the C60H3NiCp complex. The results obtained can be useful in the design of synthesis of new fullerene derivatives with the η3—π-coordination of the transition metal atoms to the carbon cage.

Hydrogenation of the nitroquinoline (I) gives the pyrroloquinoline (II) as the result of an intermolecular cyclization.