Palladium-catalysed cross-coupling of organotellurium compounds with hypervalent iodonium salts

8 Palladium-catalysed cross-coupling of organotellurium compounds with hypervalent iodonium salts 

Diaryltellurium dichlorides can be readily conpled with iodoninm salts in the presence of palladium catalyst (PdCl2, 10 mol%) and MeONa in MeCN/MeOH.  

Typical procedure. To a stirred solntion of Ph2TeCl2 (716 mg, 1.40 mmol), PdClj (25 mg, 0.14 mmol) and NaOMe (220 mg, 4.20 mmol) in CHjCN/MeOH (20 mL) under nitrogen atmosphere was added p-methoxyphenyl(phenyl)iodonium tetrafluoroborate (556 mg, 1.40 mmol) at room temperatnre. The reaction mixture was stirred at room temperature for 7 h. The reaction mixture was extracted with diethyl ether (3x20 mL). The organic layer was dried over anhydrous sodium sulphate and evaporated in vacuo. The crude product was separated by Si02 column chromatography (hexane, Rf=0.l7) to afford the conpled product (219 mg, 85%). 

9 Detellurative carbonylation of organotellurium compounds preparation of carboxylic acids 

Aryltellurium trichlorides and diaryltellurium dichlorides react with nickel tetracarbonyl in DMF, giving benzoic acids. Small amounts of diaryl tellnrides and diaryl ketones are by-products of these reactions. 

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