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Resonance integrals between different hybrid AOs do not vanish, contrary to statements in current te ts. Bonds in saturated molecules are therefore not localized. Indeed B(sp3,sp3) is much greater than the CC 71 resonance integral in conjugated hydrocarbons. Paraffins are therefore a-conjugated analogs of n-conjugated polyenes. Additivity of collective properties applies equally to both, for reasons explained by PMO theory. This is why the localized bond model successfully interprets collective properties. Cyclopropanes should then be isoconjugate with benzene and hence a-aromatic. Various anomalies concerning the chemistry of small ring compounds can be explained in this way. Delocalization in alkyl anions and radicals, due to o-conjugation, is discussed.

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Most organic reactions either are one-bond processes, involving the making and/or breaking of one bond, or take place in distinct steps, each of one-bond type. It is shown that synchronous multibond processes, involving the making and/or breaking of two or more bonds, are likely to have activation energies that are roughly double those of analogous one-bond ones, explaining the predominance of the latter. The only reactions that are currently thought to involve synchronous multibond mechanisms are multibond pericyclic reactions, the E2 reaction, and the SN2' reaction. The evidence concerning the mechanisms of these is reviewed in detail and found to provide no clear support for synchronicity. On the contrary, it seems likely that the large majority of them are nonsynchronous, taking place in steps or stages, each of one-bond type. The few exceptions Cytochrome c3 Modified Artificial Liposome. Structure, Electron Transport, and pH Gradient Generation

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