in neat (no solvent) byproducts: BrSi(CH3)3, 1-dibromo-boryl-4-trimethylsilylbenzene; (Ar), addn. of solid 1,4-bis(trimethylsilyl)benzene in portions to BBr3, warmed to 80°C for 20h; evapn. of Me3SiBr, vacuum distillation, elem. anal.;

in chloroform refluxing for 12 h (under N2 or Ar); evapn. and recrystn. from CH2Cl2/n-pentane;

tert.-butyl lithium in hexane; water; pentane