In a classical investigation, West and Rochow'established that dilithio derivatives can be prepared from a, w-dibromoalkanes and lithium metal in ether only if four or more methylene groups separate the two functions. In the reaction of lithium with dibromomethane, only 6% bis (trimethylsily1) methane was obtained after quenching with trimethylchlorosilane. On the other hand, 1, 2-dibromoethane and 1, 3-dibromopropane in a similar reaction gave no ...
