1,2-dibromo-1,2-diphenylethane

Base-promoted E2 eliminations involving 1,2-dibromo-1,2-diphenylethane have been used to learn about the stereochemical preferences of this reaction. The meso starting material gives one alkene and the dl starting material gives another. 

A poly-jr-nitrostyrene coated Pt electrode has been used for the electrocatalytic reduction of 1,2-dibromo-1,2-diphenylethane to stilbene in a CH3CN-R4NBF4 system. The turnover number for catalyst sites is estimated to be 10000 [453]. 

Elimination of HBr from meio-1,2-dibromo-1,2-diphenylethane gave cis-2-bromostilbene, while the (+) or (-) isomer gave the trans alkene. This stereospecific result, which... 

On treatment with the aromatic base pyridine (Sec. 31.8), racemic 1,2-dibromo-1,2-diphenylethane loses HBr to yield /rfl/w-l-bromo-l,2-diphenylethene in contrast, the meso dibromide loses Bri to yield /ra/w-l,2-diphenylethene. (a) Suggest a mechanism for the reaction of each stereoisomer, (b) How do you account for the difference in their behavior ... 

S,3S)-1,2-Dibromo-1,2-diphenylethane will also give (Z)-1 -bromo-1,2-diphenylethene in an anti elmination. 

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