Tadamichi Fukunaga

Unified theory of the thermodynamic and kinetic criteria of aromatic character in the [4n+2]annulenes

Abstract It is shown that there is a direct relationship between the resonance energies and the HOMO-LUMO energy gap in the [4n+2]annulenes - thereby demonstrating the connection between the thermodynamic and kinetic criteria of aromatic character.

Near Hartree-Fock relative energies of cis- and trans-1,2-difluoroethylene: The insignificance of electron correlation

Abstract The difference in energy between cis- and trans-1,2-difluoroethylene is accurately computed at the SCF level with near Hartree-Fock wavefunctions using either of two internally consistent sets of optimized geometries. The inaccuracy of calculations with smaller basis sets is attributed in part to an overestimation of C-F bond dipole-dipole repulsion in the cis isomer.

Electron impact induced fragmentation of triquinacene and related compounds—genesis and structure of C9H7+ ions in the gas phase

Abstract Triquinacene, a (CH)10 hydrocarbon, gives an intense C9H7+ peak upon electron impact. The genesis and nature of this ion were investigated by collision-induced dissociation mass spectrometry and unimolecular dissociation of metastable ions. The results demonstrate that the C9H7+ ion arises directly from the parent C10H10+ ion without prior loss of hydrogen but possesses a structure or a composition of structures essentially identical with those derived from other (CH)10 hydrocarbons and related precursors.

New organic electrolytes: tris(dialkylamino)sulfonium salts: (R2N3)S+Xμ

Abstract The electrochemical and electrical properties of tris(dimethylamino)sulfoniuin tetrafluoroborate (TASBF 4 ),a representative example of a new class of tris(dialkylamino)sulfonium salts, are described. Conductivity and cyclic voltammetric measurements were conducted in both CH 3 CN and CH 2 Cl 2 , and the results were compared with those of tetrabutylammonium tetrafluoroborate (TBABF 4 ). The peak separation of the Fc/Fc + couple is smaller with the TAS salt than with the TBA salt. The effect of electrolyte concentration and sweep rate on the peak separation is discussed. From conductivity measurements, the dissociation constants of TASBF 4 in both solvents are 20–30% larger than those of TBABF 4 . The limiting conductivity of the TAS cation in CH 3 CN (102 S cm 2 mol −1 ) is about 60% higher than that of the TBA cation.

HYDROGEN CYANIDE CHEMISTRY. 9. CYCLOADDITION REACTIONS AND NITRENIUM ION TYPE E REACTIVITY OF DIIMINOSUCCINONITRILE

Dicyan (I) liefert mit HCN das Diiminobemsteinsauredinitril (II), mit dem Cycloadditionsreaktionen durchgefuhrt werden.