Rearrangement of pyridine to its 2-carbene tautomer mediated by iridium.
نویسندگان
چکیده
The 2-carbene tautomer of pyridine (I), azacyclohexanetriene2-ylidene (II), was first proposed by Hammick1 70 years ago to explain the facile decarboxylation of 2-picolinic acid. Recent theoretical calculations2 have shown that II has energy about 4550 kcal‚mol-1 higher than I and that the transition state for the I to II rearrangement lies ca. 85 kcal‚mol-1 above I. Accordingly, the I to II tautomerization has never been achieved, although II can be generated in the gas phase by mass spectrometric experiments2 and as a ligand by protonation at the nitrogen atom of gold 2-pyridyl derivatives.3
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ورودعنوان ژورنال:
- Journal of the American Chemical Society
دوره 129 46 شماره
صفحات -
تاریخ انتشار 2007