Toluene → 1,1-bis(4-methoxyphenyl)ethylene

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Reaction Steps

A solution of 258 g 4,4'-dimethoxybenzophenone in 3000 ml warm toluene was added to 1600 ml 1.4M methylmagnesium bromide under nitrogen with stirring, over a one-hour period. The reaction temperature was kept below 40° C. After addition was complete, stirring was continued for one hour at 30°-40° C. and two hours at 50° C. The mixture was cooled to room temperature and poured into a stirred mixture of 400 ml acetic acid and 624 g ammonium chloride in 7200 ml deionized water. After gas evolution and exotherm had subsided, the organic (toluene) phase was separated and the aqueous phase was washed with 2×600 ml toluene. The combined toluene phases were washed with 1×2400 ml water, then placed in a flask and treated with a solution of 1470 ml deionized water and 1470 ml acetic acid at 50° C. for three hours to effect dehydration of the intermediate hydroxy compound. On cooling, the phases were separated and the toluene phase was washed with 2×1000 ml deionized water, then dried over magnesium sulfate. Filtration and removal of toluene gave a slightly wet cake which was triturated with 1400 ml diethyl ether, filtered and dried to give 222 g 1,1-di(p-methoxyphenyl)-ethene, m.p. 141°-143° C. whose structure was also confirmed by NMR.

Provenance & Evidence