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A new one-pot method for the synthesis of earlier unknown boron-containing adamantane derivatives, spiro[adamantane-2,2′-boriranes], via the catalytic cycloboration of methyleneadamantane with BF3·THF and RBCl2·SMe2 (R is 2-norbornyl and cyclooctyl) in the presence of Cp2TiCl2 and Mg (acceptor of halide ions) was developed. The structure of spiro[adamantane-2,2′-boriranes] was elucidated using 1D (1H, 13C, 11B, and 19F) and 2D (HSQC, HMBC, COSY, and diffusion-ordered (DOSY)) NMR techniques. 1-Fluorosubstituted spiro[adamantane-2,2′-borirane] was identified as a complex with the solvent molecule (THF) according to a comparison of the experimental and calculated 11B NMR chemical shifts and the calculation data for the thermodynamic parameters of complex formation. [ABSTRACT FROM AUTHOR]

1-Fluorine-substituted spiroboracarbocycles were first synthesized by cycloboration of monoterpenes ((–)-β-pinene, (–)-camphene, and l(–)-menthol methylene derivative) with boron trifluoride (BF3·THF) in the presence of two-component catalytic system Cp2TiCl2/Mg in tetrahydrofuran. [ABSTRACT FROM AUTHOR]

The 13C NMR chemical shifts of fullerene C60 exo-derivatives were calculated using quantum chemical hybrid functionals combined with Pople, Dunning correlation-consistent, and def2-TZVP split valence basis sets taking into account the solvent effect (polarizable continuum model). A relationship between theoretical and experimental 13C NMR chemical shifts (CSs) is assessed quantitatively to select a functional/basis set combination. It is found that the CAM-B3LYP/6-31G and M06L/6-31G combinations have the best convergence with experimental data in modeling the 13С NMR CSs of sp3 fullerene carbon atoms in С60 derivatives, whereas X3LYP/6-31G and CAM-B3LYP/6-31G(d) in modeling the 13С NMR CSs of their sp2 fullerene carbon atoms. [ABSTRACT FROM AUTHOR]

The reaction of methylidenecycloalkanes with BF3·THF in the presence of Cp2TiCl2 as catalyst has been performed for the first time to obtain 1-fluoroboriranes spiro-fused to cycloalkanes and 1-methylcycloalk-1-enes formed as a result of isomerization of the initial olefin. The product structure was confirmed by one- (1H, 13C DEPT, 11B, 19F) and two-dimensional (COSY, HSQC, HMBC) NMR and mass spectra in combination with quantum chemical calculation of 13C chemical shifts. [ABSTRACT FROM AUTHOR]

Cycloboration of methylidenecycloalkanes with PhBCl2 in the presence of Cp2TiCl2 as catalyst was performed for the first time to afford previously unknown spiro-boracarbocycles in 70–80% yields. The structure and properties of the obtained spiro-boriranes were studied by 11B, 1H, and 13C NMR and DOSY experi-ments. 1-Phenyl-substituted boraspiranes were found to be stable in solution at room temperature for 24 h. [ABSTRACT FROM AUTHOR]

The present article details a novel approach for introducing strained 2,3-dimethylenebicyclo[2,2,0]hexane structures into the C60 fullerene molecule, based on the reaction of C60 with substituted propargylamines, promoted by the Ti(Oi-Pr)4 and EtMgBr system. The theoretical LUMO energies of the strained C60 derivatives calculated at the PBEPBE/6-311G(d,p) level of theory are from −3.93 to −4.09 eV, which indicates that these compounds seem to be promising as electron-acceptor materials for bulk heterojunction organic solar cells. [ABSTRACT FROM AUTHOR]

Single crystals of (2S,5R)‐2‐isopropyl‐5‐methyl‐7‐(5‐methylisoxazol‐3‐yl)cyclohexanespiro‐3′‐(1,2,4,5,7‐tetraoxazocane), C16H26N2O5, have been studied via X‐ray diffraction. The tetraoxazocane ring adopts a boat–chair conformation in the crystalline state, which is due to intramolecular interactions. Conformational analysis of the tetraoxazocane fragment performed at the B3LYP/6‐31G(d,2p) level of theory showed that there are three minima on the potential energy surface, one of which corresponds to the conformation realized in the solid state, but not to a global minimum. Analysis of the geometry and the topological parameters of the electron density at the (3,−1) bond critical points (BCPs), and the charge transfer in the tetraoxazocane ring indicated that there are stereoelectronic effects in the O—C—O and N—C—O fragments. There is a two‐cross hyperconjugation in the N—C—O fragment between the lone electron pair of the N atom (lpN) and the antibonding orbital of a C—O bond (σ*C—O) and vice versa between lpO and σ*C—N. The oxazole substituent has a considerable effect on the geometry and the topological parameters of the electron density at the (3,−1) BCPs of the tetraoxazocane ring. The crystal structure is stabilized via intermolecular C—H...N and C—H...O hydrogen bonds, which is unambiguously confirmed with PIXEL calculations, a quantum theory of atoms in molecules (QTAIM) topological analysis of the electron density at the (3,−1) BCPs and a Hirshfeld analysis of the electrostatic potential. The molecules form zigzag chains in the crystal due to intermolecular C—H...N interactions being electrostatic in origin. The molecules are further stacked due to C—H...O hydrogen bonds. The dispersion component in the total stabilization energy of the crystal lattice is 68.09%. [ABSTRACT FROM AUTHOR]