Design and Synthesis of C(2)-Symmetric N-Heterocyclic Carbene Precursors and Metal Carbenoids
by Albright, Abigail Lynn; Eddings, Daniel Bryant; Black, Regina; Welch, Christopher J.; Gerasimchuk, Nikolay N.; Gawley, Robert E.
Chiral, C(2)-symmetric imidazolium and imidazolinium ions, as well as the corresponding copper- or silver-bound carbenoids, have been prepared. Structural study of these compounds by X-ray crystallography reveals a chiral pocket that surrounds the putative carbene site or the metal carbene bond, at carbon 2, in three of the four ligands prepared. Preliminary investigation into the application of these complexes has shown one of them to be highly enantioselective in the hydrosilylation of acetophenone.