title: Methane reacts with heteropolyacids chemisorbed on silica to produce acetic acid under soft conditions.
abstract: Selective functionalization of methane at moderate temperature is of crucial economic, environmental, and scientific importance. Here, we report that methane reacts with heteropolyacids (HPAs) chemisorbed on silica to produce acetic acid under soft conditions. Specially, when chemisorbed on silica, H(4)SiW(12)O(40), H(3)PW(12)O(40), H(4)SiMo(12)O(40), and H(3)PMo(12)O(40) activate the primary C-H bond of methane at room temperature and atmospheric pressure. With these systems, acetic acid is produced directly from methane, in a single step, in the absence of Pd and without adding CO. Extensive surface characterization by solid-state NMR spectroscopy, IR spectroscopy, cyclic voltammetry, and X-ray photoelectron spectroscopy suggests that C-H activation of methane is triggered by the protons in the HPA-silica interface with concerted reduction of the Keggin cage, leading to water formation and hydration of the interface. This is the simplest and mildest way reported to date to functionalize methane.
authors.affiliation: KAUST Catalysis Center, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia.
authors.forename: Miao
authors.initials: M
authors.lastname: Sun
authors.forename: Edy
authors.initials: E
authors.lastname: Abou-Hamad
authors.forename: Aaron J
authors.initials: AJ
authors.lastname: Rossini
authors.forename: Jizhe
authors.initials: J
authors.lastname: Zhang
authors.forename: Anne
authors.initials: A
authors.lastname: Lesage
authors.forename: Haibo
authors.initials: H
authors.lastname: Zhu
authors.forename: Jeremie
authors.initials: J
authors.lastname: Pelletier
authors.forename: Lyndon
authors.initials: L
authors.lastname: Emsley
authors.forename: Valerie
authors.initials: V
authors.lastname: Caps
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Basset