| Abstract
| - High resolution carbon-13, fluorine-19, and proton NMRmeasurements in solutions of the monosubstitutedbullvalenes, C10H9X with X = F, CN, and COOH,as function of temperature are reported. The spectra atlowtemperatures exhibit signals due to more than one isomer (three for X= F and two for X = CN, COOH). Onheating the peaks broaden due to bond shift (Cope) rearrangementinvolving the various isomers. Detailed analysisof the line shapes shows that in all cases interconversion between thefour possible isomers must be assumed, eventhough the concentration of some of them is too weak to be observed.For fluorobullvalene a complete analysis ofthe interconversion kinetics and equilibria is presented. Forcyanobullvalene and bullvalenecarboxylic acid only asemiquantitative analysis of the results was made.
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