Leung, G. Y. C.; William, A. D.; Johannes, C. W., Improved synthesis of pyridyl-biaryl ring systems via benzidine rearrangements. Tetrahedron Letters 2014, 55, (29), p 3950-3953.
Abstract:
The acid-catalyzed benzidine rearrangement of diazo compounds is known to involve several rearrangements with the major pathway being a [5,5] sigmatropic rearrangement to provide 4,4′-diaminobiaryls. A limitation of this rearrangement has been poor conversions with pyridyl systems. Herein, we address this long standing issue to furnish hetero-biaryls via a pyridinium salt in the presence of trimethylsilyl iodide.
License type:
http://creativecommons.org/licenses/by-nc-nd/4.0/
Funding Info:
Financial support for this work was provided by the Agency for Science, Technology and Research (A*STAR).