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Facile Pd(II)- and Ni(II)-catalyzed isomerization of terminal alkenes into 2-alkenes.

ABSTRACT: Mono- and 2,2'-disubstituted terminal alkenes can be isomerized into the more stable internal (Z)- and (E)-alkenes by treating them with catalytic amounts of [(allyl)PdCl](2) or [(allyl)NiBr](2), a triarylphosphine, and silver triflate at room temperature. The isomeric ratio (E:Z) depends on the alkenes, the E-isomer being the major one. The reaction is tolerant to a wide variety of functional groups including other reactive olefins. Unlike the more reactive Ir catalysts, monosubstituted alkenes give almost exclusively the 2-alkenes. Direct comparison to two of the best-known catalysts for this process {[Ir(PCy(3))(3)](+)[BPh(4)](-) and Grubbs generation II metathesis catalyst} is also described.

SUBMITTER: Lim HJ

PROVIDER: S-EPMC2715430 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature

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Facile Pd(II)- and Ni(II)-catalyzed isomerization of terminal alkenes into 2-alkenes.

Lim Hwan Jung HJ Smith Craig R CR RajanBabu T V TV

The Journal of organic chemistry 20090601 12

Mono- and 2,2'-disubstituted terminal alkenes can be isomerized into the more stable internal (Z)- and (E)-alkenes by treating them with catalytic amounts of [(allyl)PdCl](2) or [(allyl)NiBr](2), a triarylphosphine, and silver triflate at room temperature. The isomeric ratio (E:Z) depends on the alkenes, the E-isomer being the major one. The reaction is tolerant to a wide variety of functional groups including other reactive olefins. Unlike the more reactive Ir catalysts, monosubstituted alkenes ...[more]

PMID: 19441793

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