Hydrophobic Acceleration of Electron-Transfer Fluorescence Quenching Processes between Excited 1-Alkanoylperylenes and Ferrocene Derivatives

Coaggregation-facilitated Electron-transfer (ET) fluorescence quenching processes between an excited 1-alkanoylperylene (Pe-n, n = 4, 8, 12) as an acceptor and an 1-alkanoylferrocene (Fc-m, m = 4, 8, 12, 16) or a 1,1-dialkanoylferrocene (Fc-m-2, m =4, 8, 12, 16) as a donor have been investigated by means of fluorescence spectroscopy in dioxane (DX)-H₂O binary solvents of different Θ values, where Θ is the volume fraction of the organic component of an aquiorgano mixture. This is a first observation of an ET processes facilitated by hydrophobic-lipophilic interaction (HLI) with organometallic compounds as donors. The extent of HLI-driven co-aggregation between the acceptor and the donor may be assessed from the efficiency of fluorescence quenching, i. e., the slope B of Eq. (2). The chain-foldability effect and the intramolecular “self-satisfaction” of HLI for Fc-m-2 have been observed. The experimental results show that the behavior of Fc-m as a quencher for fluorescence quenching of Pen is rather similar to that of N-alkylsubstituend phenothiazine.