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Published on: November 12, 2016
Computed ammonia affinity for evaluating Lewis acidity of organoboronates and organoboronamides
Hideya Tanaka1, Masaaki Nakamoto1, Hiroto Yoshida1
1Graduate School of Advanced Science and Engineering, Hiroshima University Higashi-Hiroshima 739-8526 Japan yhiroto@hiroshima-u.ac.jp.
Abstract:
Lewis acidity of organoboronates [B(pin), B(neop), B(cat), B(eg), B(nad)] and organoboronamides [B(dan), B(aam), B(mdan)] has been found to be unifiedly evaluated by computed ammonia affinity (AA), while other methods [LUMO energies, global electrophilicity index (GEI), fluoride ion affinity (FIA)] were only partially applicable. The relationships between the AA values and such structural characters including the B-X bond lengths, the X-B-X angles, and the changes in the B-X bond lengths in the formation of the ammonia adducts were also described.
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