2,2 -biphenyldiyl- -4,4 -dimethyl

Dimethyl-2,2 -biphenyldiyl 4,4 -Dimethyl-2 -bromo-2-biphenyl Telluronium Bromide1 200 mg (0.41 mmol) of bis[4,4 -dimethyl-2,2 -biphenyldiyl] tellurium are suspended in 20 ml of carbon tetrachloride, the suspension is cooled in an ice/salt bath, and bromine is added dropwise with stirring until the brown color of bromine persists. The precipitate is filtered, washed with carbon tetrachloride, and dried yield 226 mg (85%) m.p. 278° (from dichloromcthane/ diethyl ether). 

Dimethyldibenzotellurophene. Powder tellurium (0.94 g 7.4 mmol) is thoroughly mixed with 2.61 g (6.1 mmol) of pure 4,4-dimethyl-2,2 -biphenyldiyl mercury, the mixture is placed into a sublimation apparatus equipped with a cold finger, and slowly heated under vacuum in a metal bath to 260-270°C. Colourless needles begin to sublime at 228°C. The temperature is held at 260°C for 12 h. The sublimate is recrystallized from a mixture of 300 mL of methanol and 10 mL of carbon tetrachloride. Yield 1.38 g (79%) m.p. 158°C. Dibenzotellurophene was similarly obtained in 82% yield. 

C14H12 = 3,3 -dimethyl-4,4 -biphenyldiyl j) Mol- % ratio ethylene terephthalate to oxybenzoate... 

Bis-[4,4 -dimethyl-2,2 -biphenyldily]- E2, 904 Bis-[4-methy[-2,2 -biphenyldiyl]- E2, 904 (Bis-[trimcthylsiIyI]-amino)-diniethyl-phenyl- ... 

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