W0090

Acid-Base Interactions Between Au(I) and Electrophiles. Structures of Pi-Acid Organics and Related Materials With Trinuclear Au(I) Carbeniates and Benzylimidazolates. John P. Fackler, Jr., Ahmed A. Mohamed, Mohammad A. Omary, Richard J. Staples, Chemistry, Texas A&M University, 3255 TAMU, College Station, TX 77843 USA.

It is well established that the Au(I) center in many linear 2-coordinate Au(I) complexes displays electrophilic tendencies in reaction chemistry although also accepting electron donors to expand the coordination in some systems. For example, linear 2-coordinate cations such as [AuL₂]⁺, where L = phosphine, will add additional phosphine to form 3-coordinate and 4-coordinate species which have been structurally characterized. Yet, dinuclear ylide complexes of Au(I) react with electrophiles to form Au(II) oxidative addition products. With trinuclear carbeniates and related species, stable Au(II) species cannot form for stereochemical reasons. Yet, these compounds readily interact with cations such as Tl⁺ and Ag⁺ wherein the cations interact with six Au(I) centers of two trinuclear units. This unusual behavior led us to examine the interaction with pi metal organic such as [Hg(C₆H₄)]₃ where we found pi-acid pi-base behavior in the solid state and in solution. Further studies identified pi-acid pi-base interactions with TCNQ, C₆F₆, and also C₁₀F₈ (Octafluoronaphthalene). In this report the various structural features will be discussed including DFT calculations related to the acid-base character of the components structured.