Synthesis and structure of binuclear single-bridged bis[(phosphane)gold(I)]halogenonium complexes

Reactions of (R(3)P)AuX (X = Cl, Br, I) with [(R(3)P)Au](+) BF4-, obtained from (R(3)P)AuCl and AgBF4 in tetrahydrofuran, lead to cationic binuclear gold(I) complexes of the general formula {[(R(3)P)Au](2)X}(+) BF4-. A number of chloro- (R = Ph, o-Tol, Mes, Bzl, Et), bromo- (R = Ph, o-Tol, Mes) and iodo-bridged (R = Ph, Mes) complexes of this type have been isolated and identified on the basis of their analytical and spectroscopic data. The crystal structure of bis[(triphenylphosphane)gold(I)]bromonium tetrafluoroborate was determined by single-crystal X-ray diffraction. The cations contain two-coordinate bromine atoms with an Au-Br-Au angle of 96.83(3)degrees.