Selective formation of trans-2-butene-1,4-d/sub 2/ and (E)-2-methyl-2-butene-1,4-d/sub 2/ in deuteration of 1,3-butadiene derivatives over thorium oxide catalyst
Stereoselective hydrogenations of 1,3-butadiene and 2-methyl-1,3-butadiene over thorium oxide catalyst were investigated to elucidate the intermediates of the reactions. Hydrogenation of 1,3-butadiene produced predominantly trans-2-butene. Deuterium tracer studies provided direct evidence that 1,4-addition was a dominant mechanism. Deuteration of 1,3-butadiene yielded exclusively monoenes-d/sub 2/, while no deuterium was exchanged with hydrogen in 1,3-butadiene. Deuteration of 2-methyl-2-butene gave mainly (E)-2-methyl-2-butene-1,4-d/sub 2/. For both reactants, most stable conformations of starting diens (s-trans form) were reflected on the structure of the products. The geometrical structures as well as molecular identity of a hydrogen molecule were maintained during hydrogenation. Reaction of a mixture containing 1-butene and 1,3-butadiene-d/sub 6/ in the presence of hydrogen revealed that 1-butene and 1,3-butadiene independently underwent isomerization and hydrogenation, respectively. The nature of their active sites is discussed. Key intermediate of the hydrogenation of conjugated diene is postulated to be the syn form of methyl- or dimethyl-..pi..-allyl carbanion which is hydrogenated before interconverting to their isomeric anti form of the ..pi..-allyl carbanion. 5 figures, 6 tables.
- Research Organization:
- Hokkaido Univ., Sapporo, Japan
- OSTI ID:
- 6337644
- Journal Information:
- J. Catal.; (United States), Vol. 56:3
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
BUTENES
CHEMICAL REACTION YIELD
DEUTERIUM
ISOTOPIC EXCHANGE
DIENES
CHEMICAL REACTIONS
LABELLING
HYDROGEN
THORIUM OXIDES
CATALYTIC EFFECTS
AMMONIA
CARBON DIOXIDE
CARBON MONOXIDE
CATALYSTS
CHEMICAL REACTION KINETICS
COMPARATIVE EVALUATIONS
DEUTERIUM COMPOUNDS
EXPERIMENTAL DATA
ISOLATED VALUES
ISOMERIZATION
LOW PRESSURE
MASS SPECTRA
MEDIUM TEMPERATURE
MIXTURES
NUCLEAR MAGNETIC RESONANCE
OXYGEN
POISONING
PRESSURE DEPENDENCE
REACTION INTERMEDIATES
SPECTRAL SHIFT
TEMPERATURE DEPENDENCE
TIME DEPENDENCE
TRACER TECHNIQUES
WATER
ACTINIDE COMPOUNDS
ALKENES
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
CRYOGENIC FLUIDS
DATA
DATA FORMS
DISPERSIONS
ELEMENTS
FLUIDS
HYDRIDES
HYDROCARBONS
HYDROGEN COMPOUNDS
HYDROGEN ISOTOPES
INFORMATION
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
LIGHT NUCLEI
MAGNETIC RESONANCE
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
NONMETALS
NUCLEI
NUMERICAL DATA
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POLYENES
REACTION KINETICS
RESONANCE
SPECTRA
STABLE ISOTOPES
THORIUM COMPOUNDS
YIELDS
400303* - Organic Chemistry- Isotope Exchange & Isotope Separation- (-1987)
400301 - Organic Chemistry- Chemical & Physicochemical Properties- (-1987)