title: Acceptorless dehydrogenation of small molecules through cooperative base metal catalysis.
abstract: The dehydrogenation of unactivated alkanes is an important transformation both in industrial and biological systems. Recent efforts towards this reaction have revolved around high temperature, organometallic C-H activation by noble metal catalysts that produce alkenes and hydrogen gas as the sole products. Conversely, natural desaturase systems proceed through stepwise hydrogen atom transfer at physiological temperature; however, these transformations require a terminal oxidant. Here we show combining tetra-n-butylammonium decatungstate (TBADT) and cobaloxime pyridine chloride (COPC) can catalytically dehydrogenate unactivated alkanes and alcohols under near-UV irradiation at room temperature with hydrogen as the sole by-product. This noble metal-free process follows a nature-inspired pathway of high- and low-energy hydrogen atom abstractions. The hydrogen evolution ability of cobaloximes is leveraged to render the system catalytic, with cooperative turnover numbers up to 48 and yields up to 83%. Our results demonstrate how cooperative base metal catalysis can achieve transformations previously restricted to precious metal catalysts.
authors.affiliation: Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: Julian G
authors.initials: JG
authors.lastname: West
authors.affiliation: Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: David
authors.initials: D
authors.lastname: Huang
authors.affiliation: Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Sorensen
mesh_terms: D000473:Alkanes / Q000737:chemistry*; D002384:Catalysis; D006859:Hydrogen / Q000737:chemistry*; D008670:Metals / Q000737:chemistry*
chemical_list: D000473:Alkanes; D008670:Metals; D006859:Hydrogen