title: Catalytic borylation of methane.
abstract: Despite steady progress in catalytic methods for the borylation of hydrocarbons, methane has not yet been subject to this transformation. Here we report the iridium-catalyzed borylation of methane using bis(pinacolborane) in cyclohexane solvent. Initially, trace amounts of borylated products were detected with phenanthroline-coordinated Ir complexes. A combination of experimental high-pressure and high-throughput screening, and computational mechanism discovery techniques helped to rationalize the foundation of the catalysis and identify improved phosphine-coordinated catalytic complexes. Optimized conditions of 150°C and 3500-kilopascal pressure led to yields as high as ~52%, turnover numbers of 100, and improved chemoselectivity for monoborylated versus diborylated methane.
authors.affiliation: Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA 19104, USA.
authors.forename: Kyle T
authors.initials: KT
authors.lastname: Smith
authors.affiliation: Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA 19104, USA.
authors.forename: Simon
authors.initials: S
authors.lastname: Berritt
authors.affiliation: Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA 19104, USA.
authors.forename: Mariano
authors.initials: M
authors.lastname: González-Moreiras
authors.affiliation: Institute for Basic Science-Center for Catalytic Hydrocarbon Functionalizations, Daejeon, Korea. Department of Chemistry, Korea Advanced Institute of Science and Technology, Daejeon, Korea.
authors.forename: Seihwan
authors.initials: S
authors.lastname: Ahn
authors.affiliation: Department of Chemistry, Michigan State University, 578 South Shaw Lane, East Lansing, MI 48824, USA. smithmil@msu.edu mbaik2805@kaist.ac.kr mindiola@sas.upenn.edu.
authors.forename: Milton R
authors.initials: MR
authors.lastname: Smith
authors.affiliation: Institute for Basic Science-Center for Catalytic Hydrocarbon Functionalizations, Daejeon, Korea. Department of Chemistry, Korea Advanced Institute of Science and Technology, Daejeon, Korea. smithmil@msu.edu mbaik2805@kaist.ac.kr mindiola@sas.upenn.edu.
authors.forename: Mu-Hyun
authors.initials: MH
authors.lastname: Baik
authors.affiliation: Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA 19104, USA. smithmil@msu.edu mbaik2805@kaist.ac.kr mindiola@sas.upenn.edu.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Mindiola