Some studies in perhaloaromatic chemistry

A review of recent advances of the chemistry of polyhalogenaromatic compounds, with an emphasis placed on the uses of the corresponding lithium and Grignard derivatives in the formation of polyhalogenaromatic complexes of metals and metalloids is presented. 1,2,3-Tribromotrifluorobenzene was prepared by the decomposition of 1-lithio-2-bromotetrafluorobenzene in the presence of dry lithium bromide, and its structure elucidated from 19F and 13C nuclear magnetic resonance studies. Mass spectral analysis of the reaction products showed the presence of 1,2,3,4-tetrabromodifluorobenzene, formed by further attack of n-butyllithium on the tri-bromo-derivative with subsequent decomposition in the presence of lithium bromide. Polybromobiphenyls, having molecular formulae C12F7Br3 and C12F6Br4 were detected in the reaction products by mass spectrometry and mechanisms are given to account for their formation. [Continues.]