Gas-phase studies of alkane oxidation by transition-metal oxides. Selective oxidation by CrO/sup +/

Journal Article · Tue Nov 25 23:00:00 EST 1986 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00284a011· OSTI ID:6953141

Kang, H; Beauchamp, J L

The gas-phase reactions of CrO/sup +/ with alkanes have been studied by using ion beam reactive scattering techniques. CrO/sup +/ undergoes facile reactions with alkanes larger than methane. CrO/sup +/ selectively oxidizes ethane to form ethanol. In addition to the possibility of alcohol formation, reactions with larger alkanes are more complex, yielding products in which dehydrogenation and loss of alkenes and alkanes occur. In reactions with cyclic alkanes, cyclopropane and cyclobutane yield products characteristic of C-C bond cleavage. In contrast, reactions with cyclopentane and cyclohexane mainly involve dehydrogenation and elimination of H/sub 2/O. A series of hydrogen abstraction reactions are examined to determine the bond dissociation energy D/sup 0/ (CrO/sup +/-H) = 89 +/- 5 kcal mol/sup -1/. This bond energy has implications for the reaction mechanisms of CrO/sup +/ with alkanes, leading to the suggestion of a multicenter reaction intermediate, in which alkyl C-H bonds add across the Cr/sup +/-O bond as an initial step. This is supported by an examination of the reactions of Cr/sup +/ with alcohols.

• Research Organization: California Institute of Technology, Pasadena
• OSTI ID: 6953141
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 108:24; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALCOHOLS
ALKANES
BINDING ENERGY
BUTANE
CHALCOGENIDES
CHEMICAL PREPARATION
CHEMICAL REACTIONS
CHROMIUM COMPOUNDS
CHROMIUM OXIDES
COLLISIONS
CYCLOALKANES
CYCLOHEXANE
DATA
DEHYDROGENATION
ENERGY
ETHANE
ETHANOL
EXPERIMENTAL DATA
FLUIDS
GASES
HYDROCARBONS
HYDROXY COMPOUNDS
INFORMATION
ION COLLISIONS
ION-MOLECULE COLLISIONS
MOLECULE COLLISIONS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANOMETALLIC COMPOUNDS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PENTANE
PROPANE
REACTION INTERMEDIATES
SYNTHESIS
THERMODYNAMICS
TRANSITION ELEMENT COMPOUNDS