Chemistry and spectroscopy in strongly acidic solutions. Part XX: Configurational equilibration in protonated formic acid and protonated acetic acid (dihydroxycarbonium ions): (Short communication)

In a number of protonated organic molecules configurational isomerism around a partly double CO bond has recently been established2. We thought it of interest to determine the energy barriers of configurational equilibration around this bond (and similar partly double bonds), and to compare these experimentally determined activation energies with those calculated quantum-mechanically3. For dimethoxymethylcarbonium ion this barrier was recently determined to be 11 ± 4 kcal · mole−1.

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