Pd II -catalysed cross-coupling of vinylic tellurides with alkenes

2 Pd(II)-catalysed cross-coupling of vinylic tellurides with alkenes 

Vinylic and divinylic tellnrides react with alkenes in MeOH in the presence of a combination of catalytic amounts of PdCl2 together with AgOAc and EtjN to afford the corresponding vinyl-substituted alkenes The products result respectively from the coupling of the styryl and phenyl moieties of the starting telluride with retention of its double-bond stereochemistry. 

Vinylic tellurides react with Grignard reagents under Ni(II) or Co(II) complex catalysis giving cross-coupling products, with results that depend on the nature of the substrate or the Grignard reagent.  

By submitting tellurophene to a similar treatment 1,4-disubstituted (Z,Z)-(l,3)-buta-dienes are formed.  

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