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The electrochemistry of perfluorotetracyclobuta-l,3,5,7-cyclooctatetraene (1) (a flat cyclooctatetraene) shows two reversible one-electron reductions at 0.79 and 0.14 V vs. SCE. The apparent electron-transfer rate constant for the first reduction is 0.07 ± 0.02 cm/s. The first reduction potential of 1 is more than 2.3 V positive of cyclooctatetraene (COT), and the apparent rate constant is more than an order of magnitude higher. It is suggested that the larger electron transfer rate constant for 1 compared with COT is due to the lower molecular reorganization energy required to reach the transition state for electron transfer. The unusually positive reduction potential of 1 is probably due at least in part to the 16 fluorine atoms.We report our findings on the electrochemistry of perfluorotetracyclobuta-1,3,5,7-cyclooctatetraene,1 1, which is one of the most powerful neutral organic oxidants known, reducing at positive 0.79 V vs. SCE.

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Electrochemical reduction of meso-and dZ-2,4-dibromopentane (2) in dimethyl sulfoxide affords in each case roughly equal amounts of cisand irans-l,2-dimethylcyclopropanes (7 and 8, respectively). The results are interpreted in terms of a stepwise reduction mechanism, via a 7-halo carbanion ( 13). (-)-(2E,4ñ)-2,4-Pentanediol was prepared by resolution of the racemic diol; the diol was then converted by means of phosphorus tribromide in pyridine into (+ )-(2S,4S)-2. Electrochemical reduction of this material afforded ( -)-(lif,2ñ)-8 of high optical purity, demonstrating that cyclization of 13 occurs via a semi-W transition state. The reduction of dl and optically active 2 by a number of chemical reducíants was also examined.There exists a wide variety2 3of reactions which amount to overall 1,3 elimination of two substituents with formation of a carbon-carbon bond, i.e.

Meeting of The Electrochemical Society in Washington, D.C., May 1971. Financial support was provided by the National Science Foundation. The Wesleyan University Computing Center provided computer time.