4-methoxyphenyl phenylethynyl

Bis[4-methoxyphenyl] Ditellurium1 Sodium borohydride (81 mg, 2.2 mmol) in 3 ml ethanol is added to 670 mg (2.0 mmol) of 4-methoxyphenyl phenylethynyl tellurium in 10 ml ethanol at 40°. The solution is stirred for 10 min then 0.5 ml water and 0.5 ml of 10% aqueous sodium hydroxide are added. The mixture is cooled to 0J and stirred for 10 min. The mixture is then diluted with 30 ml diethyl ether, then washed with brine, and the organic layer separated, dried with anhydrous magnesium sulfate, filtered, and the solvent evaporated from the filtrate. Phenylacctylene iscautiously evaporated at reduced pressure and collected in a trap cooled to — 78°. The residue is recrystallized from diethyl ether yield 95% m.p. 58°. 

Methoxyphenyl phenylethynyl tellurium produced bis[4-methoxyphenyl ditellurium upon treatment with sodium borohydride in ethanol in the presence of air1. The sodium 4-methoxybenzenetellurolate is an intermediate in this reaction. 

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