title: Intramolecular rearrangement for regioselective complexation by intramolecular CH/pi interaction in a hydrophobic cavity of a ruthenium coordination sphere.
abstract: A Ru(II) complex with a hydrophobic cavity formed from two 1-naphthoylamide groups was prepared. Its reactions with beta-diketones gave beta-diketonato complexes in which hydrophobic pi-pi or CH/pi interactions were confirmed by NMR spectroscopy and X-ray crystallography. In the case of the asymmetric beta-diketone benzoylacetone, an isomer with a CH/pi interaction was afforded as the sole product owing to thermodynamic control. The reaction was found to involve a novel intramolecular rearrangement from the phenyl-included isomer to the methyl-included one without rupture of Ru-beta-diketonato coordination bonds (activation energy 52 kJ mol(-1)). This indicates that CH/pi interactions can be more favored thermodynamically than pi-pi interactions in a suitable hydrophobic environment.
authors.affiliation: Department of Chemistry, Faculty of Sciences, Kyushu University, Hakozaki, Higashi-Ku, Fukuoka 812-8581, Japan.
authors.forename: Takahiko
authors.initials: T
authors.lastname: Kojima
authors.forename: Soushi
authors.initials: S
authors.lastname: Miyazaki
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Hayashi
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Shimazaki
authors.forename: Fumito
authors.initials: F
authors.lastname: Tani
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Naruta
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Matsuda
mesh_terms: D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D009930:Organic Chemicals / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry*
chemical_list: D009930:Organic Chemicals; D012428:Ruthenium