Anion‐Directed Copper(II) Metallocages, Coordination Chain, and Complex Double Salt: Structures, Magnetic Properties, EPR Spectra, and Density Functional Study

Abstract

A series of Cu(II) metallo-assemblies showing anion-directed structural variations, including five metallocages [(G(n-) )⊂{Cu2 (Hdpma)4 }]((8-n)+) (A(-) )8-n (G(n-) =NO3 (-) , ClO4 (-) , SiF6 (2-) , BF4 (-) , SO4 (2-) ; A(-) =NO3 (-) , ClO4 (-) , BF4 (-) , CH3 SO4 (-) ; Hdpma=bis(3-pyridylmethyl)ammonium cation), a complex double salt, namely, (H3 dpma)4 (CuCl4 )5 Cl2 , and a coordination chain, namely, [Cu2 (dpma)(OAc)4 ], are reported. The influence of the anion can be explained by its coordinating ability, the affinity of which for the Cu(II) center interferes significantly with metallocage formation, and its shape, which offers host-guest recognition ability to engage in weak metal-anion coordination and hydrogen bonding to the organic ligand, which are responsible for metallocage templation. EPR studies of these metallocages in the powder phase at room temperature and 77 K showed a trend of the g values (g|| >2.10>g⊥ >2.00) indicating a dx2-y2 -based ground state with square-pyramidal geometry for the Cu(II) centers. The magnetism of these metallocages can be interpreted as the result of a combination of relatively small magnetic coupling integrals and a substantial contribution of temperature-independent paramagnetism (TIP). The weak magnetic interaction is corroborated by the results of DFT calculations and the EPR spectra. Availability of the low-lying state for spin population was confirmed by a magnetization study, which revealed a magnetic moment approaching 2Nβ, which would explain the presence of the larger TIP term.

Synthesis and Structure–Property Relationships in Herbicidal Ionic Liquids and their Double Salts

“…However, the obtained DSHILs retained the same solubility characteristics as HILs comprising a MCPA anion for all solvents, excluding acetonitrile, which turned out to be immiscible with all the double salts ( 1 d – 7 d ). Interestingly, previously reported data supports the possibility of such divergence in the physicochemical properties between organic salts and their double salts . Further investigation allowed for identification of the undissolved fraction as dicamba‐based HILs, whereas HILs comprising MCPA appeared to be fully dissolved.…”

“…Interestingly,p reviously reported data supports the possibility of such divergence in the physicochemicalp roperties between organic salts and their double salts. [44,45] Further investigation allowed for identification of the undissolved fraction as dicamba-basedH ILs, whereas HILs comprising MCPAa ppeared to be fully dissolved. Thus, these findings provide au seful tool to decompose theD SIL into individual components based on selecting an appropriate solvent, one capable of selectived issolution of only one of the ILs utilized for preparation of ad ouble salt.…”

Directed Phase Transfer of an FeII4L4 Cage and Encapsulated Cargo

“…Because these cages are not charge neutral, − they derive properties from both cation and anion. Counterions have previously been shown to play a significant role in the stability, − shape, − solubility, and other physicochemical properties , of coordination cages. We further demonstrate in this work that exchanging cage counterions can drive spontaneous and quantitative transport of cages from water across a phase boundary and into an ionic liquid. − In an advance over cation transport driven by anionic phase transfer catalysts, , our strategy allows the simultaneous transfer of selectively bound guest molecules.…”