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    Molecular complexes of substituted diphenyl sulphides with π acceptors. Charge transfer spectra and ionization potentials of the donors
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1974, 70 (10), 1974) Aloisi, G. Gaetano; Santini, Sergio; Sorriso, Salvatore
    Charge transfer complexes of substituted diphenyl sulphides as donors with tetracyanoethylene, 2,3-dichloro-5,6-dicyano-p-benzoquinone and chloranil have been studied spectrophotometrically. From the energies of the charge transfer transitions, the ionization potentials of the donors have been obtained. From the formation constants of the complexes and ionization potentials of the donors evidence has been obtained on the mixed nature of the donor orbital. The role of inner valence orbitals in the complex formation is also discussed.
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    Molecular Complexes: Part 11.'—Sonic Comments on Electrostatic and Steric Effects in the Formation of Acrylonitrile + Aromatic Complexes
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1974, 70 (1-6), 1974) Homer, John; Yadava, Raja R.
    The interactions between acrylonitrile and various alkylbenzenes have been studied by 1H n.m.r. at several temperatures. The equilibrium quotients, Kx, and aromatic induced shifts, Δc, at a particular temperature, as well as ΔG°, ΔH° and ΔS° appear superficially to show an almost random variation with the degree of alkylation of the aromatic nucleus. However, the data have been rationalized in a quantitative fashion by considering that the reaction and complex parameters are governed by three factors. These are due to an intermolecular electrostatic effect and two steric features of the aromatic compounds due to the “blocking” and “trapping” effects of the alkyl substituents.
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    Molecular Complexes: Part 12- Use of Phase Distribution and Nuclear Magnetic Resonance Methods to Elucidate the Mechanism of the Acetone + Benzene Reaction
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1974, 70 (1-6), 1974) Homer, John; Cooke, Melvyn C.
    The results of studies of the acetone+benzene interaction obtained from a phase distribution technique and the conventional n.m.r. approach are compared. This reveals that the conventional n.m.r. approach to studies of molecular complexes can be misleading. In resolving the inherent problems a mechanism for the acetone + benzene reaction is proposed. The reaction is studied in the presence of carbon tetrachloride and cyclohexane separately. It is shown that whereas carbon tetrachloride is reactive towards benzene, cyclohexane is less so and that data obtained by both experimental techniques using this material as solvent provide values for the equilibrium quotient, Kx, and aromatic induced shift, Ac, which are in good agreement.
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    Molecular complexes of substituted thiophens with σ and π acceptors: Charge transfer spectra and ionization potentials of the donors
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1973, 69 (3), 1973) Aloisi, Gian Gaetano; Pignataro, Salvatore
    Charge transfer complexes of substituted thiophens as donors with tetracyanothylene, 2,3-dichloro-5,6-dicyano-p-benzoquinone, chloranil and iodine have been studied spectrophotometrically. From the energies of the charge transfer transitions, the ionization potentials of the donors have been obtained. Comparison with those measured by electron-impact mass spectrometry, shows that the thiophens behave as π donors with all four acceptors. In the case of iodine the stability constants of the complexes support a π→σ* interaction. Some evidence is given for the role of inner valence orbitals in the complexes.