Alkynes to Vinyl Carboxylic Acids

Acetylenes react with arenetellurolates to form aryl vinyl tellurides. The vinyl groups in vinyl aryl telluriums are converted to vinyl carboxylic acids by carbon monoxide in the presence of stoichiometric amounts of palladium dichloride or diacetate The yield and the product distribution is influenced by the reaction time, the CO pressure, the presence or absence of lithium chloride or triethyl amine, and the concentration of palladium salt. Diphenyl tellurium was converted to benzoic acid Hexyl phenyl tellurium formed only benzoic acid and no heptanoic acid.  

These reactions can be made catalytic with respect to palladium(II) chloride when copper(II) chloride is used as oxidant.  

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