Lithium sulfate, radical

A round-bottom flask was charged with a mixture of 2,6-dimethylphenyl trifluoromethanesulfonate (127.1 mg, 0.5 mmol), anhydrous lithium chloride (4 mmol), copper(I) bromide (0.2 mmol), and dichlorobis(triphenylphosphine)-palladium(II) (10-20 mol %) suspended in DMF (2.5 cm ). 2-Methoxyphenyl-tributyltin (1-1.5 mmol) was added to the mixture in two portions, i.e., at the beginning of the reaction and at half completion. A crystal of 2,6-bis(l,l-dime-thylethyl)-4-methylphenol (BHT) was added as an inhibitor of radical processes, and the mixture was then heated to reflux, under argon, during 8 - 24 h. Water and Et20 (25 cm ) was added, and the organic phase was washed subsequently with hydrochloric acid solution (1.5 mol dm , 6 x 20 cm ), a saturated solution of potassium fluoride (5 x 20 cm ), and finally dried over anhydrous sodium sulfate. Evaporation to dryness furnished a residue and that was suspended in ethyl acetate and the insoluble material was filtered off. The filtrate was... 

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