METAL DERIVATIVES OF AZOLES .3. PYRAZOLATO ANION (AND HOMOLOGS) AS A MONODENTATE OR BIDENTATE LIGAND - PREPARATION AND REACTIVITY OF TRINUCLEAR, BINUCLEAR, AND MONONUCLEAR GOLD(I) DERIVATIVES

Stable gold(I) derivatives of several azoles, [Au(az)]n, are obtained by various routes (azH=pyrazole or various 1-unsubstituted pyrazoles, benzo-1, 2, 3-triazole, or 1, 2, 4-triazole). In these compounds the main- group acts as an exobidentate N, N' ligand; in several cases n=3, and a trinuclear, enneaatomic ring structure is suggested. On the other hand, in the monomeric compounds Ph3PAu(az) where azH is benzotriazole or 3, 5-dimethyl-4-nitropyrazole (pz'H) the azolato anion is monodentate. The compound Ph3PAu(pz') reacts with [(CO)2RhCl]2 affording (CO)2Rh(μ-pz')RMCO)2 and with fluoboric acid or AgBF4 yielding [Ph3PAu(μ-pz')AuPPh3]+BF4-, where only one exobidentate pyrazolato-N, N' bridges two gold atoms. The trimeric gold(I) pyrazolates, Au3(pz)3, react with iodine to give Au3(pz)3I2, probably mixed-valence compounds, while with. sym-trinitrobenzene an unstable 1:1 charge-transfer adduct is obtained and with iodine chloride the coordinated ligand is iodinated in the 4-position affording tris(3, 5-dimethyl-4-iodopyrazolato-N, N')trigold(I). © 1979, American Chemical Society. All rights reserved.