A Chelating Triscarbene Ligand and Its Hexacarbene Iron Complex

Abstract

A free tricarbene is most likely a long-lived intermediate in the formation of the first hexacarbene iron complex 1 (R = Me) from trimethylated tris(1-imidazolyl)borate, n-butyllithium, iron chloride, and tetraphenylborate. This tripodal C,C′,C″-chelating ligand, for which the authors predict a brilliant future, is an isomer of Trofimenko's tris(1-pyra-zolyl)borate and represents a novel class of negatively charged six-electron donors with the greatest possible similarity to the cyclopentadienyl anion.