Pentafluorophenylcopper: Complexation behavior and supramolecular structures

INOR 225

Ami Doshi1, Krishnan Venkatasubbaiah1, Anand Sundararaman1, Lev N. Zakharov2, Arnold.L. Rheingold, arnrhein@chem.ucsd.edu2, Roger A. Lalancette, N/A1, and Frieder Jäkle, fjaekle@andromeda.rutgers.edu1. (1) Department of Chemistry, Rutgers University-Newark, 73 Warren Street, Olson Hall, Newark, NJ 07102, (2) Department of Chemistry and Biochemistry, University of California - San Diego, 9500 Gilman Drive, San Diego, CA 92093
Organocopper species are widely used in organic synthesis, catalysis and as luminescent materials. Organo-copper(I) compounds form a variety of different aggregates in solution as well as in the solid state. Pentafluorophenylcopper crystallizes from non-coordinating solvents as a tetrameric aggregate with short Cu-Cu distances of ~ 2.4 Å. In contrast, crystallization from toluene leads to formation of the π-complex [(C6F5)Cu]4(η2-toluene)2. Coordination of nucleophiles such as pyridine to tetrameric pentafluorophenylcopper leads to break-down of the aggregate to give monomeric species, which in turn form supramolecular structures via cuprophilic and π-stacking interactions. Stacks that involve the intact tetramer have also been realized. These supramolecular stacks show interesting photophysical properties, which have been examined by variable temperature solid-state photoluminescence studies.