Isomerizations of olefins

Isomerization of olefins can be accomplished also in the gas phase m a flow reactor with alumina or nickel oxide as catalyst Thus perfluoro 2-butene can be prepared by passing perfluoro-1 butene over these catalysts at 150-400 °C [79] Similar results may be obtained in an autoclave with the same catalysts Perfluoro-1 butene isomenzes almost quantitatively at 250 °C after 100 h to perfluoro-2-butene [20]... 

The Homogeneous Catalytic Isomerization of Olefins by Transition Metal Complexes... 

Opposing reactions. Consider the kinetics of the N02-catalyzed isomerization of olefins. Derive the expression shown for kCV]. where KTC = k,mns/kCiS, in experiments starting only with m-olefin,11... 

Aryl ketones are often used to effect cis and tram isomerization of olefins.(118-ia0) Although this, in some cases, can be viewed as an energy transfer process where the ketone triplet transfers its energy to the olefin, which then isomerizes, the failure of noncarbonyl sensitizers of comparable triplet energy to isomerize the olefins suggests that a process other than energy transfer may be involved. Schenck and Steinmetz<118) suggested that isomerization results from decomposition of a biradical carbonyl-olefin adduct similar to that involved in oxetane formation ... 

Olefin hydrogenation catalyzed by Fe(CO)s normally requires somewhat severe conditions, typically 150°C and 10 atm H2 (/, p. 64). With near-ultraviolet irradiation the carbonyl becomes effective at ambient conditions for hydrogenation (and isomerization) of olefins (448, 449). Photoinduced labilization of carbonyls is thought to give tricarbonyl species as the active catalysts, e.g.,... 

Methyldichlorosilane was by far the most reactive in hydrosilation of 1,1-disubstituted olefins. Trialkylsilanes did not add at all, even at 120°C. Trichlorosilane gave complicated results involving isomerization of olefins and dimerization of a-methylstyrene, and products were not optically active. 2-Methylbutene-2 and trichlorosilane gave two adducts, 2-meth-ylbutyltrichlorosilane and 3-methylbutyltrichlorosilane. The latter required isomerization of the olefin. 2,3-Dimethylbutene-l gave one adduct in 70% yield, and it was optically slightly active [0.8% (R) isomer]. 

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