Hyun Jee Kim

Ligand- and Anion-Directed Assembly of Exo-Coordinated Mercury(II) Halide Complexes with O2S2-Donor Macrocycles

Assembly reactions of mercury(II) halides (Cl, Br, and I) with two O2S2 macrocycles (L(1) and L(2)) having different interdonor (S...S) distances were investigated, and four types of supramolecular complexes (1-4b) were obtained depending on the S...S distances as well as the size of the halide anions. Photoluminescence of these compounds was also studied.

Anion-controlled endo- and exocyclic disilver(I) complexes of an S2O3 macrocycle.

Anion-controlled endo- and exocyclic complexes were afforded in the reactions of an S(2)O(3) macrocycle with AgPF(6) and AgClO(4), respectively. The two coordination modes that provide the Ag ion position inside (by PF(6)(-)) or outside (by ClO(4)(-)) the macrocyclic cavity are explained by the anion-coordination ability toward the metal cation. Furthermore, each Ag center bridges two ligands via a regular coordinative bond or by pi coordination, forming a cyclic dimeric-type product. NMR titrations of the complex system in solution were also carried out.

A Calix‐bis‐crown with Hard and Soft Crown Cavities: Heterobinuclear K+/Ag+ Complexation in Solid and Solution States

Calixcrowns offer particular utility since the fusion of calixarene and crown ether units enables the divergent orientation of cavities of a size and nature sufficient to accommodate a variety of guests. Among them, calix[4]-bis-crowns with a 1,3-alternate conformation (or saddle-type) have interesting features including 1) two crown cavities able to undergo dinucleation and 2) HSAB-based complexation selectivity. Kim et al. reported the synthesis of a heterodinuclear complex of an unsymmetrical calix-bis-crown with two different size crown loops: a crown-5 and a crown-6 suitable for K and Cs , respectively. We recently reported the examples of calix[4]-bis-dithiacrown based, endo-coordinated disilver(I) complexes as well as an exo-coordinated 3D network connected by CuI-based clusters. Despite the existence of systems exhibiting 1) and 2) above, neither the preparation nor the crystal structure of any calixcrowns, which are designed to accommodate hard and soft metal ions in their individual cavities, has been reported previously. In view of this, we have focused our attention to the synthesis and characterization on a new calixbis-crown system designed to bind both soft and hard metal ions within its respective cavities. In preliminary work, we synthesized an unsymmetrical calix[4]-bis-crown, in which oxaand thiaoxa-crown rings are simultaneously bound to the calixarene scaffold. However, in this case the synthesized species with monothiaoxaand dithiaoxa-crown as the softer rings failed to accommodate Ag probably a result of K–Ag repulsion rather than a lack of complexation affinity for Ag . These results motivated us to optimize the ligand structure for this ion through the modification of the thiaoxa-crown unit and prepared the unsymmetrical calix[4]arene (4) incorporating O5/ O2S3-bis-crown rings ACHTUNGTRENNUNG(Scheme 1). To the best of our knowl-

Hard/soft heterometallic network complex of a macrocycle with endo/exocyclic coordination.

One-pot assembly reactions of an S(2)O(4) macrocycle with CuI in the absence and presence of KI afforded an emissive one-dimensional looped coordination polymer linked with a cubane-type copper iodide cluster and an endocoordinated potassium(I) coordination polymer linked with a ribbon-type copper iodide cluster, respectively.

Endo- and/or exocyclic silver(I) and mercury(II) complexes of an NO2S2-macrocycle: effect of ligand ratio and anion

Synthesis and structural behaviours of a pyridine-containing NO2S2-macrocycle L and its soft metal complexes 1–4 with different types of coordination modes and topologies are presented. The reactions of L with AgPF6 in different ligand-to-metal ratios lead to the formation of two solid complexes with different topologies: an endocyclic 1:1 (L:M) complex 1a and an unprecedented 2:1 endo/exo-type complex 2. NMR titrations confirm that both silver(I) complexes with 1:1 and 2:1 ratios also retain in solution. In the reactions of L with HgCl2 and Hg(ClO4)2, anion-controlled exo- and endocyclic 1:1 complexes were afforded, respectively. The tendency to adopt this respective arrangement suggests the possibility that metal coordination modes and/or topologies including the stoichiometries can be controlled by varying ligand-to-metal ratios and anions.

Anion-dependent coordinative networking of macrocycle with copper(I) halides

An O2S2-macrocycle L incorporating three aromatic subunits was synthesized and structurally characterized by X-ray analysis. Four coordination polymers of L with copper(I) halides (Cl, Br and I) adopting different topologies and network patterns depending on the anions are reported. Reactions of L with copper(I) chloride and copper(I) bromide yielded a single-stranded one-dimensional (1D) coordination polymer [CuCl2(L)(CH3CN)]n (1) with an oxidized copper(II) centre and a double-stranded 1D coordination polymer [(Cu2Br2)(L)2]·4CH2Cl2]n (2), with each strand linked by a rhomboid-type Cu2Br2 unit. However, the reaction with copper(I) iodide under the same conditions gave an emissive mixture of supramolecular isomers with an identical composition {[Cu4I4(L)2]·CH2Cl2}n, adopting a regular (3a) and a tilted (3b) square-grid-type 2D coordination polymers via cubane-type Cu4I4 linking. The XRPD results also confirmed the binary mixture. The conformational diversity in the ligand leads to a variation in overall structural motifs of the supramolecular isomers.

Exo-coordinated discrete and continuous supramolecular silver(I) complexes with thiaoxa-macrocycles

Two thiaoxa-macrocycles (L1: S3O2 and L2: S2O3) with a dibenzo-subunit were synthesised and structurally characterised by X-ray analysis. Reactions of L1 and L2 with silver(I) salts (NO3− and PF6−) afforded the respective ligand- and/or anion-directed complexes 1–3 with different topologies; tetranuclear sandwich [Ag4(L1)2(NO3)4] (1), cyclic tetramer [Ag4(L1)4](PF6)4 (2) and poly(bicyclic dimer) [Ag(L2)NO3]n (3). The formation of such supramolecular complexes is discussed in terms of donor or anion effect.

Macrocyclic isomer-dependent supramolecular silver(I) complexes via endo/exo-coordination modes: a tetranuclear bis(macrocycle) complex vs. a 2D coordination polymer

A comparative investigation of the coordination behaviour of the regio-isomers (o-L and p-L) of the tribenzo-O2S2-macrocycle (L) is reported. On silver(I) complexation, the macrocycle incorporating an o-xylyl group (o-L) yields a discrete endo/exocyclic tetranuclear bis(macrocycle) complex. On the other hand, the corresponding p-xylyl analogue (p-L) gives a 2D square-grid coordination network via exocyclic coordination.

Surprisingly stable ammonium ion complex of a non-cyclic crown-type polyether: solid and solution studies

The first crystal structure of an NH4+ ion complex with 1,13-bis(8-quinolyl)-1,4,7,10,13-pentaoxatridecane (L), a representative non-cyclic analogue of 18-crown-6, is reported along with the characteristics of the complex’s solution; very interestingly, L forms a more stable complex with the NH4+ ion than does 18-crown-6 by the formation of unique recognition tetrahedral-type hydrogen bonds.