A straightforward synthetic route to symmetric bis(acetylide) metallates of the coinage metals

A novel generalized synthetic procedure for bis(acetylide) metallates(I) of the coinage metals [K(THF)n(18-crown-6)][R-C≡C-M-C≡C-R] (M = Cu, Ag, Au) with varying substituents R (R = Fc, Ph, tBu) was developed. The synthesis proceeded under mild conditions by deprotonation of the corresponding alkyne with K{N(SiMe3)2}, followed by salt metathesis reactions with CuCl, AgCl or AuCl(tht) (tht = tetrahydrothiophene) in the presence of 18-crown-6. The herein obtained anionic compounds represent interesting potential building blocks for homo- and heterometallic clusters.