Specific Enhancement of Catalytic Activity by a Dicopper Core: Selective Hydroxylation of Benzene to Phenol with Hydrogen Peroxide

Tomokazu Tsuji; Antonius Andre Zaoputra; Yutaka Hitomi; Kaoru Mieda; Takashi Ogura; Yoshihito Shiota; Kazunari Yoshizawa; Hiroyasu Sato; Masahito Kodera

doi:10.1002/anie.201702291

Specific Enhancement of Catalytic Activity by a Dicopper Core: Selective Hydroxylation of Benzene to Phenol with Hydrogen Peroxide

Angew Chem Int Ed Engl. 2017 Jun 26;56(27):7779-7782. doi: 10.1002/anie.201702291. Epub 2017 May 31.

Authors

Tomokazu Tsuji¹, Antonius Andre Zaoputra¹, Yutaka Hitomi¹, Kaoru Mieda², Takashi Ogura², Yoshihito Shiota³, Kazunari Yoshizawa³, Hiroyasu Sato⁴, Masahito Kodera¹

Affiliations

¹ Department of Molecular Chemistry and Biochemistry, Doshisha University, Kyotanabe, Kyoto, 610-0321, Japan.
² Department of Life Science, University of Hyogo, Kouto, 2-1, Ako-gun, Kamigori-cho, Hyogo, 678-1297, Japan.
³ Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka, 819-0395, Japan.
⁴ Application Laboratory, Rigaku Corporation, Akishima, Tokyo, 196-8666, Japan.

PMID: 28561921
DOI: 10.1002/anie.201702291

Abstract

A dicopper(II) complex, stabilized by the bis(tpa) ligand 1,2-bis[2-[bis(2-pyridylmethyl)aminomethyl]-6-pyridyl]ethane (6-hpa), [Cu₂ (μ-OH)(6-hpa)]³⁺ , was synthesized and structurally characterized. This complex catalyzed selective hydroxylation of benzene to phenol using H₂ O₂ , thus attaining large turnover numbers (TONs) and high H₂ O₂ efficiency. The TON after 40 hours for the phenol production exceeded 12000 in MeCN at 50 °C under N₂ , the highest value reported for benzene hydroxylation with H₂ O₂ catalyzed by homogeneous complexes. At 22 % benzene conversion, phenol (95.2 %) and p-benzoquinone (4.8 %) were produced. The mechanism of H₂ O₂ activation and benzene hydroxylation is proposed.

Keywords: arenes; copper; oxidation; reaction mechanisms; structure elucidation.

Publication types

Research Support, Non-U.S. Gov't