Preparation of (E)-1-Alkenylboronic Acid Pinacol Esters via Transfer of Alkenyl Group from Boron to Boron
Kazuya Shirakawa, Akira Arase, Masayuki Hoshi*
*Department of Applied and Environmental Chemistry, Kitami Institute of Technology, 165 Koen-cho, Kitami, Hokkaido 090-8507, Japan Email: hoshi-mchem.kitami-it.ac.jp
K. Shirakawa, A. Arase, M. Hoshi, Synthesis, 2004, 1814-1820.
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A mild hydroboration of various 1-alkynes with pinacolborane was achieved in the presence of a catalytic amount of dicyclohexylborane at room temperature under neat conditions to afford the corresponding (E)-1-alkenylboronic acid pinacol esters in good yields.
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proposed catalytic cycle
(E)-1-alkenylboronic acid pinacol ester, 1-alkyne, dicyclohexylborane, catecholborane, pinacolborane, hydroboration