Carbon-hydrogen bond activation and carbon-carbon bond formation in the reaction between ethylene and hexaisopropoxyditungsten
Ethylene reacts with certain metal surfaces to give a capping (..mu../sub 3/) ethylidyne ligand. In triosmium carbonyl chemistry ethylene has been shown to undergo successive C-H activation to give a ..mu..-sigma,..pi..-vinyl and a ..mu..-vinylidene ligand. A similar reaction sequence has been reported by Puddephatt and co-workers in the addition of ethyne to a hydrido triangulo platinum complex. The authors have repeatedly emphasized the relationships, both structural and chemical, between reduced metal oxides of molybdenum and tungsten and smaller alkoxide clusters and their larger (closo) counterparts. For example, the square-Mo/sub 4/Cl/sub 4/(O-i-Pr)/sub 4/ and butterfly-Mo/sub 4/Br/sub 4/(O-i-Pr)/sub 2/ molecules are arachno subunits of the M/sub 6/(..mu../sub 3/-X)/sub 8/ cluster unit, and W/sub 4/(O-i-Pr)/sub 12/ represents a fragment of the M/sub 6/(..mu../sub 2/-X)/sub 12/ unit. Furthermore the M/sub 4/-alkoxide clusters are formed from the coupling of M/sub 2/ alkoxides by steric control in the choice of the OR group. Indeed the authors have established that an equilibrium exists between W/sub 4/(O-i-Pr)/sub 12/ and W/sub 2/(O-i-Pr)/sub 6/. One of the authors hypotheses is that these small unsaturated alkoxide cluster units may provide models for active sites on reduced metal oxide surfaces. They describe here the observation of the activation of ethylene by W/sub 2/(O-i-Pr)/sub 6/ under extremely mild conditions.
- Research Organization:
- Indiana Univ., Bloomington
- OSTI ID:
- 5890716
- Journal Information:
- J. Am. Chem. Soc.; (United States), Vol. 109:19
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ETHYLENE
CHEMICAL REACTIONS
ORGANOMETALLIC COMPOUNDS
TUNGSTEN COMPLEXES
ACTIVATION ENERGY
CARBON
CHEMICAL BONDS
EXPERIMENTAL DATA
HYDROGEN
ALKENES
COMPLEXES
DATA
ELEMENTS
ENERGY
HYDROCARBONS
INFORMATION
NONMETALS
NUMERICAL DATA
ORGANIC COMPOUNDS
TRANSITION ELEMENT COMPLEXES
400201* - Chemical & Physicochemical Properties