Mechanistic Studies on Photoinduced Catalytic Olefin Migration Reactions at the Pd(II) Centers of a Porous Crystal, Metal-Macrocycle Framework

Hirotaka Yonezawa; Takafumi Shiraogawa; Mengying Han; Shohei Tashiro; Masahiro Ehara; Mitsuhiko Shionoya

doi:10.1002/asia.202001306

Mechanistic Studies on Photoinduced Catalytic Olefin Migration Reactions at the Pd(II) Centers of a Porous Crystal, Metal-Macrocycle Framework

Chem Asian J. 2021 Feb 1;16(3):202-206. doi: 10.1002/asia.202001306. Epub 2020 Dec 22.

Authors

Hirotaka Yonezawa¹, Takafumi Shiraogawa², Mengying Han¹, Shohei Tashiro¹, Masahiro Ehara², Mitsuhiko Shionoya¹

Affiliations

¹ Department of Chemistry Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
² Institute for Molecular Science and SOKENDAI, Myodaiji, Okazaki, Aichi, 444-8585, Japan.

PMID: 33300244
DOI: 10.1002/asia.202001306

Abstract

Porous crystals with well-defined active metal centers on the pore surface have high potential as heterogeneous metal catalysts. We have recently demonstrated that a porous molecular crystal, metal-macrocycle framework (MMF), catalyzes olefin migration reactions by photoactivation of its Pd^II Cl₂ moieties exposed on the crystalline channel surface. Herein we report a mechanistic study of the photoinduced olefin migration reactions at the Pd^II active centers of MMF. Several experiments, including a deuterium scrambling study, revealed that olefin migration is catalyzed via an alkyl mechanism by in situ generated Pd-H species on the channel surface during photoirradiation. This proposed mechanism was further supported by DFT and ONIOM calculations.

Keywords: mechanism; metallacycles; olefin migration; palladium; photoactivation.

Abstract

Grants and funding