title: On the mechanism of the conversion of methanol to 2,2,3-trimethylbutane (triptane) over zinc iodide.
abstract: Methanol is converted to a mixture of hydrocarbons by reaction with zinc iodide at 200 degrees C with one highly branched alkane, 2,2,3-trimethylbutane (triptane), being obtained in surprisingly high selectivity. Mechanistic studies implicate a two-stage process, the first involving heterogeneously catalyzed formation of a carbon-carbon-bonded species, probably ethylene, that undergoes homogeneously catalyzed sequential cationic methylation to higher hydrocarbons. The first stage can be bypassed by addition of olefins, higher alcohols, or arenes, which act as initiators. Rationales for the particular activity of zinc iodide and for the selectivity to triptane are proposed.
authors.affiliation: Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology, Pasadena, California 91125, USA.
authors.forename: John E
authors.initials: JE
authors.lastname: Bercaw
authors.forename: Paula L
authors.initials: PL
authors.lastname: Diaconescu
authors.forename: Robert H
authors.initials: RH
authors.lastname: Grubbs
authors.forename: Richard D
authors.initials: RD
authors.lastname: Kay
authors.forename: Sarah
authors.initials: S
authors.lastname: Kitching
authors.forename: Jay A
authors.initials: JA
authors.lastname: Labinger
authors.forename: Xingwei
authors.initials: X
authors.lastname: Li
authors.forename: Parisa
authors.initials: P
authors.lastname: Mehrkhodavandi
authors.forename: George E
authors.initials: GE
authors.lastname: Morris
authors.forename: Glenn J
authors.initials: GJ
authors.lastname: Sunley
authors.forename: Patrick
authors.initials: P
authors.lastname: Vagner