2008/10/04 by Hyojong Yoo, Chad A. Mirkin, Antonio G. DiPasquale +2 · 1 citation
Chemistry · Materials Science · #Supramolecular Chemistry and Complexes #Metal-Organic Frameworks: Synthesis and Applications #Porphyrin and Phthalocyanine Chemistry
paper · doi:10.1021/ic8008909
The urea moiety, which acts as a good hydrogen-bond donor, has been incorporated into a hemilabile phosphinoalkyl thioether ligand. Upon reaction of the ligand with a Rh(I) precursor, a tweezer complex with near-parallel planar urea moieties 2 forms. The host-guest interaction of 2 with Cl(-) has been characterized in solution and in the solid state. Cl(-) binding with the urea groups in 2 is retained under CO in nonpolar solvents to give a five-coordinate CO adduct 3. In polar solvents, CO binding to Rh(I) results in a Cl(-) shift from the urea host site to the Rh(I) metal center with a concomitant breaking of the Rh-S bonds. This is an unusual example of how two types of different interactions important in molecular recognition (ligand coordination to a metal and hydrogen bonding) can be regulated within one molecule through small-molecule coordination chemistry.