Catalysis of the ring-opening and isomerization of cyclopropane by complexation with metal radical cations: An ab initio study

Journal Article · Wed Dec 30 04:00:00 EST 1992 · Journal of the American Chemical Society; (United States)

DOI:https://doi.org/10.1021/ja00053a028· OSTI ID:6305502

Alex, A; Clark, T ^[1]

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1. Friedrich-Alexander-Universitaet Erlangen-Nuernberg (Germany)

The ring opening and isomerization of cyclopropane are shown by ab initio calculations to be catalyzed by complexation with Be[sup [sm bullet]+]. The reactions proceed via a common metallacyclobutane radical cation intermediate formed in a reaction that is endothermic by 12.3 kcal mol[sup [minus]1] relative to the cyclopropane-Be[sup [sm bullet]+] complex. From this intermediate, three alternative reaction paths were examined, two isomerizations to give a propene-Be[sup [sm bullet]+] complex and a C-C bond cleavage forming a carbene-ethylene-Be[sup [sm bullet]+] species. These reactions are found to be exothermic by 5.4 and 5.2 kcal mol[sup [minus]1] relative to the cyclopropane-Be[sup [sm bullet]+] complex, respectively. The isomerization of cyclopropane to give propene is calculated to be exothermic by 8.0 kcal mol[sup [minus]1] (exptl 7.9 kcal mol[sup [minus]1]). Remarkable parallels to transition-metal catalyzed reactions were found for all the reactions examined. 35 refs., 1 fig., 3 tabs.

• OSTI ID: 6305502
• Journal Information: Journal of the American Chemical Society; (United States), Journal Name: Journal of the American Chemical Society; (United States) Vol. 114:27; ISSN JACSAT; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALKALINE EARTH METALS
ALKANES
ALKENES
BERYLLIUM
CATALYSIS
CATALYTIC EFFECTS
CATIONS
CHARGED PARTICLES
CHEMICAL REACTIONS
CLEAVAGE
ELEMENTS
ENTHALPY
ETHYLENE
HYDROCARBONS
IONS
ISOMERIZATION
MATHEMATICAL MODELS
METALS
MICROSTRUCTURE
ORGANIC COMPOUNDS
PHYSICAL PROPERTIES
PROPANE
PROPYLENE
RADICALS
REACTION HEAT
THERMODYNAMIC PROPERTIES