Olefin arylation by Pd II -catalysed carbodetelluration of aryltellurium compounds

4 Olefin arylation by Pd(II)-catalysed carbodetelluration of aryltellurium compounds 

The Pd(II)-catalysed arylation of olefins by means of different aryltellurium(IV) chlorides has been more extensively investigated.  

The reactions are performed treating diarylteUurium dichlorides or aryltellurium trichlorides with excess olefin (5-10 mol equiv) in the presence of Pd(II) chloride-sodium acetate in refluxing acetic acid or acetonitrile. The yields are moderate to good with the dichlorides and poor with the trichlorides. Minor amounts of biaryls are the usual by-products beyond acetoxylated arylalkenes (formed by the addition of acetic acid to the olefins). 

The reactions can also be performed catalytically using Pd(II) chloride if a suitable oxidant such as t-butyl hydroperoxide or Cu(ll) chloride is added to the system. 

The products exhibit the E configuration, with the exception of the acrylonitrile and methacrylonitrile derivatives. 

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