CH/π Interactions Implicated in the Crystal Structure of Transition Metal Compounds − A Database Study

Abstract

A statistical study was carried out to investigate the role of the CH/π interaction in the crystal structure of transition metal compounds. Thus, short CH/π distances were surveyed in crystal structures deposited in the Cambridge Structural Database. Among organometallic entries bearing C6 or C5 aromatic rings, a substantial part of the structures has been found to have intermolecular CH/π contacts shorter than the van der Waals distance. Further, in many structures short intramolecular CH/π contacts have been found. Interligand and intraligand CH/π interactions were also surveyed in coordination compounds bearing the typical ligands 1,10-phenanthroline, 2,2′-bipyridine, and 2,2′:6′,2′′-terpyridine, as well as triphenylphosphane complexes of ruthenium, rhenium, and rhodium. The results were discussed in the context of the CH/π interaction in controlling the crystal packing and the molecular structure of transition metal compounds. The compact structure with CH/π interactions is a general aspect in coordination and organometallic chemistry. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)