PREPARATION AND STRUCTURE OF POLY(GOLD)TELLURONIUM SALTS

Tris[(triphenylphosphine)gold(I)]telluronium teratrafluoroborate (1) w as prepared from the corresponding oxonium salt and bis(t-butyldimethy lsilyl)tellurium in dichloromethane at -78 degrees C. The product form s yellow crystals, thermally stable to 125 degrees C. It was identifie d by standard analytical and spectroscopic techniques, including a sin gle crystal X-ray diffraction study In the crystal lattice, the cation s form tellurium-capped triangles of gold, which are associated into d imers through short intermolecular Au-Au contacts, resembling those in the corresponding sulfur and selenium compounds. - The reaction of (t -BuMe(2)Si)(2)Te with four equivalents of {[(Ph(3)P)Au]Te-4}(2+) 2 BF4 - in tetrahydrofuran at -78 degrees C gives a tetranuclear compound, { [(Ph(3)P)Au]Te-4}(2+) 2 BF4- (2) which differs from 1 in its analytica l and spectroscopic data. Its structure could not be determined, but i t is assumed that the dications have a square pyramidal geometry.