Reconfirmation of Solubility of C22− in Liquid Ammonia: Syntheses and Crystal Structures of the Tetrahedral Acetylide Ammoniates [Zn(C2H)4]2−, [Cd(C2H)4]2− and [In(C6H5)3(C2H)] −

Abstract

AbstractThe new compounds with the sum formulae [Cs([18]crown‐6)]2[Zn(C2H)4] ⋅ 8NH3, Rb3[Rb([18]crown‐6)(NH3)][Cd(C2H)4]2 ⋅ {[18]crown‐6 ⋅ 2NH3} ⋅ NH3 and [Cs([2.2.2]crypt)][In(C6H5)3(C2H)] were synthesized in liquid ammonia. The anionic units show tetrahedrally coordinated central atoms with four hydrogenacetylide ligands or one C2H− and three C6H5− ligands. Solid state starting materials for these ligands were either AC2H (A=Rb, Cs) or Cs2C2. The fact that the indium compound contains a hydrogenacetylide ligand, which was formed from Cs2C2, confirms again the equilibrium of the species C2H2, C2H− and C22− in liquid ammonia and again proves that acetylides slowly dissolve in this medium.