Aromatic compounds of arsenic, phosphorus and antimony can be prepared readily through the use of diazonium fluoborates.'It was of interest to determine whether other stable diazonium salts could be used in place of fluoborates. In particular, the diazonium fluosilicates seemed worth considering since they are, at least in some cases, more stable2 and easier to isolatea than the corresponding fluoborates.