Synthesis, Crystal Structure and Properties of [Cu(phen) 3 ][Cu(pheida) 2 ]·10H 2 O and [(phen) 2 Cu( μ ‐BAAP)Cu( μ ‐BAAP)Cu(phen) 2 ][Cu(BAAP) 2 ]·8.5H 2 O (H 2 pheida = N‐phenetyl‐iminodiacetic acid, H 2 BAAP = N‐benzylaminoacetic‐2‐propionic acid)

The salts [Cu(phen) 3 ][Cu(pheida) 2 ]·10H 2 O ( 1 ) and [(phen) 2 Cu(μ‐BAAP)Cu(μ‐BAAP)Cu(phen) 2 ][Cu(BAAP) 2 ]·8.5H 2 O ( 2 ) (H 2 pheida = N‐phenetyl‐iminodiacetic acid, H 2 BAAP = N‐benzylaminoacetic‐2‐propionic acid, phen = 1, 10‐phenanthroline) have been prepared and studied by thermal, spectroscopic and X‐ray diffraction methods. 1 has the rather unusual [Cu(phen) 3 ] 2+ cation and two non‐equivalent [Cu(pheida) 2 ] 2— anions with a coordination type 4+2 but quite different tetragonality (T = 0.848 and 0.703 for anions 1 and 2, respectively). The crystal consists of multi‐π, π‐stacked chains (…anion 2 — cation — cation — anion 2…) connected by hydrophobic interactions; these chains build channels which are partially filled by anions 1 and water molecules. In contrast, compound 2 has a mixed‐ligand trinuclear cation with a bridging central moiety close similar to the counter anion. The formation of such a trinuclear cation is discussed as a consequence of the most advantageous molecular recognition process between [Cu(phen) 2 (H 2 O) 1 or 2 ] 2+ and [Cu(BAAP) 2 ] 2— in solution. In the crystal of 2, multi‐π, π‐stacked arrays of C 6 ‐rings from phen and (BAAP) 2— ligands of trinuclear cations generate channels where counter anions and water molecules are located.