Ancillary ligands and spectator cations as controlling factors in the construction of coordination and hydrogen-bonded networks with the tert-Bu-C≡C⊃Ag_n (n = 4, 5) supramolecular synthon

Supramolecular networks constructed with the tBu-C≡C⊃Ag _n (n = 4 or 5) metal-ligand synthon and trifluoroacetate have been transformed through the introduction of ancillary terminal nitrile ligands, from acetonitrile through propionitrile to tert-butyronitrile, giving rise to a 2D coordination network in AgC≡ CtBu·3 AgCF₃CO ₂·H₂O (1), a 2D hydrogen-bonded network in AgC≡ CtBu·5 AgCF₃CO₂·4 CH ₃CN·H₂O (2), a 2D hybrid coordination/hydrogen- bonded network in AgC≡ CtBu·3 AgCF₃CO ₂·CH₃CH₂CN·2 H₂O (3), and another 2D coordination network in AgC≡CtBu·4 AgCF ₃CO₂· (CH₃)₃CCN· 2H₂O (4). Concomitantly, the linkage modes between adjacent ethynide-bound Ag_n aggregates in these compounds are also changed. A layer-type hydrogen-bonded host lattice in isostructural AgC≡ CtBu·4 AgCF₃CO₂·(R₄N)(CF ₃CO₂)· 2 H₂O (R₄ = BnMe ₃, 5; R₄ = Et₄, 6; R₄ = nPr ₄, 7) is obtained by introducing quaternary ammonium cations as guest templates, which occupy the interstices and thereby mediate the interlayer separation. Use of the bulky nBu₄N⁺ cation leads to disruption of the host network in AgC≡CtBu·4 AgCF ₃CO₂·3-[(nBu₄N)(CF₃CO ₂)]·H₂O (8) with generation of a discrete dense nido-Ag₅ cluster.