title: Highly dispersed Pd species active in the Suzuki-Miyaura reaction.
abstract: Structures of Pd/zeolites immersed in solvents were measured by in situ X-ray absorption fine structure (XAFS). Systematic studies revealed that the selection of an appropriate support (USY-zeolite), thermal treatment temperature of USY, solvent (o-xylene), H(2) partial pressure (6%), and the use of a Pd amine complex affect the structure of Pd. As a result, we found that monomeric Pd can be obtained in the USY support with H(2) bubbling in o-xylene. The structural properties of Pd correlate well with its catalytic performance in the Suzuki-Miyaura coupling reactions; a very high TON of up to 11,000,000 was obtained over the monomeric Pd.
authors.affiliation: Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Koyama-cho Minami, Tottori-city, Tottori, Japan. okmr@chem.tottori-u.ac.jp
authors.forename: Kazu
authors.initials: K
authors.lastname: Okumura
authors.forename: Hirosuke
authors.initials: H
authors.lastname: Matsui
authors.forename: Takuya
authors.initials: T
authors.lastname: Tomiyama
authors.forename: Takashi
authors.initials: T
authors.lastname: Sanada
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Honma
authors.forename: Sayaka
authors.initials: S
authors.lastname: Hirayama
authors.forename: Miki
authors.initials: M
authors.lastname: Niwa