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A series of trinuclear lanthanide circular helicates [Ln3L3]Cl3 have been synthesized via supramolecular subcomponent self-assembly. Photophysical studies demonstrate that the unique helical bis-tetradentate 1,29-dialdehyde ligand L2− could serve as an effective sensitizer for SmIII, EuIII, NdIII and YbIII ions exhibiting efficient characteristic fluorescence emission because of the shell-type blocking of the ligand, which makes them the first circular helicates exhibiting near-infrared lanthanide fluorescence. [ABSTRACT FROM AUTHOR]

Using a mixed ligand strategy, ten new luminescent coordination polymers (LCPs), namely, [Cd(IPA-NH2)(Htpim)]n (1), [Mn(IPA-NH2)(Htpim)]n (2), [Zn(IPA-OH)(Htpim)]n (3), [Cd(IPA-OH)(Htpim)]n (4), {[Zn(Htpim)2(H2O)2](IPA-OH)}n (5), {[Cd(Htpim)2(H2O)2](IPA-OH)}n (6), [Cd(IPA-NO2)(Htpim)]n (7), [Zn2(PMA)(Htpim)2]n (8), [Cd2(PMA)(Htpim)2]n (9) and [Cu(H2PMA)(Htpim)2(H2O)]n (10) (Htpim = 2,4,5-tri(4-pyridyl)-imidazole, H2IPA-NH2 = 5-aminoisophthalic acid, H2IPA-OH = 5-hydroxyisophthalic acid, H2IPA-NO2 = 5-nitroisophthalic acid, H4PMA = 1,2,4,5-benzenetetracarboxylic acid) were constructed. Compounds 1–4 and 7–9 have similar 2D 44 networks, while 5, 6 and 10 show 1D chain structures. The results reveal that the coordination configuration of M(II), carboxylic acids, and coordinated water molecules play pivotal roles in the formation of the final structures. Moreover, the selective luminescence sensing and photocatalytic performances of 1–10 were also studied. Interestingly, they can sensitively detect trace amounts of nitrobenzene (NB), Cr2O72− or Fe3+ through luminescence quenching. In addition, 3–10 show high photocatalytic activities toward the degradation of rhodamine B (RhB). [ABSTRACT FROM AUTHOR]

This Frontier article reviews diverse structures of Schiff-base macrocyclic ZnII complexes derived from a family of flexible pendant-armed extended dialdehydes via a preorganized synthetic strategy and the corresponding structure-determining factors, including primary cationic template effects and secondary complementary template effects. In addition, further post-modification and supramolecular self-assembly of Schiff-base ZnII macrocycles and their possible applications in a variety of areas have been discussed. [ABSTRACT FROM AUTHOR]

A series of Ni(ii), Pd(ii) and Pt(ii) complexes [ML][PF6]2 [L = L1, M = Ni (1), Pd (2), Pt (3); L = L2, M = Ni (4), Pd (5), Pt (6)] and [Pt(L2)(acac)] (7) have been prepared by the reactions of two tetradentate macrocyclic amine-NHC ligand precursors, [H2L1][PF6]2 and [H2L2][PF6]2, with Ni(OAc)2·4H2O, Pd(OAc)2 and Pt(acac)2 in the presence of NaOAc. Complex 7 is isolated along with 6 from the same reaction between [H2L2][PF6]2 and Pt(acac)2. There are two atropisomers in 1–3 and two achiral conformers in 4–6. The crystal structures of 1–3 and one conformer of 4–6 (4a–6a) have been determined by single-crystal X-ray diffraction studies. The metal ion is found to reside in the cavity of the macrocyclic ring and adopts a square-planar configuration. Detailed NMR studies including variable-temperature NMR spectroscopy reveal a dynamic interconverting process between two atropisomers of 1–3 in the solutions via a ring twisting mechanism. Two conformers in the equilibrated solution of 4–6, probably arising from the orientation of two amine N–H bonds with respect to the coordination plane, exchange slowly. Time-dependent 1H NMR spectra show that one conformer (4a–6a) in solution converts into the other (4b–6b) via the inversion of the nitrogen atom. [ABSTRACT FROM AUTHOR]

Fourteen Ag(i), Au(i), Ni(ii), Pd(ii), and Pt(ii) complexes with macrocyclic tetradentate N-heterocyclic carbene (NHC) ligands were prepared via reactions between three macrocyclic tetrabenzimidazolium salts and metal precursors. All except two Au complexes were characterized using single-crystal X-ray diffraction. Three different structures, including a trinuclear one containing a NHC–Ag–(H2O) moiety and a hexanuclear propeller-like supramolecular assembly, are found for Ag–NHC complexes. Nine complexes of group 10 metal ions adopt square-planar geometry, in which the different ring-sizes of the macrocyclic tetracarbene ligands lead to a variation of metal–carbene bond lengths. π–π stackings are observed between the rigid aromatic benzimidazole rings in the nickel group complexes. [ABSTRACT FROM AUTHOR]

Reactions of [Et4N][Tp*WS3(CuCl)3] (1) (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) with 2 equiv. of AgOTf (OTf− = trifluoromethanesulfonate) and 1 equiv. of several bidentate pyridine ligands including 2,5-bis(pyridine-4-yl)thiazolo[5,4-d]thiazole (L1), 2,7-di(pyridin-4-yl)-9H-fluorene (L2), 2,7-di(pyridin-4-yl)-9H-carbazole (L3), and 2,7-di(pyridin-4-yl)-9H-fluoren-9-one (L4) afforded four W/Cu/S cluster-based supramolecular compounds [(Tp*WS3Cu2Cl)2(L1)] (2), {[(Tp*WS3Cu3)2(μ-Cl)2(μ4-Cl)]2(L2)2}(OTf)2 (3), {[(Tp*WS3Cu3)2(μ-Cl)2(μ4-Cl)]2(L3)2}(OTf)2 (4) and {[(Tp*WS3Cu3)2(μ-Cl)2(μ4-Cl)]2(L4)2}(OTf)2 (5). Compounds 2–5 were characterized by elemental analysis, IR, UV-vis, 1H NMR, and single-crystal X-ray diffraction analysis. The neutral cluster 2 behaves as a supramolecular wire constructed by L1 bridging two butterfly-shaped [Tp*WS3Cu2Cl] cores. The cluster cations of 3–5 contain two [(Tp*WS3Cu3)2(μ-Cl)2(μ4-Cl)]+ cores linked by two L2, L3, or L4 ligands, which finally formed a cationic supramolecular rectangle. The third-order nonlinear-optical (NLO) properties of 3–5 in DMF were also investigated by Z-scan techniques and their NLO responses were enhanced compared to those of their precursor 1. [ABSTRACT FROM AUTHOR]

Enantioselective synthesis of tetrahydroisoquinolines bearing an all-carbon quaternary stereogenic center, was achieved via asymmetric C–H activation with high enantioselectivities (up to 93% ee). Fair substrate tolerance was indicated throughout the scope investigation and no evident loss of enantioselectivity was exhibited in late-stage derivatization. This study provides incentives for the construction of diverse chiral isoquinoline derivatives, which are prevalent among pharmaceuticals, natural products, etc. [ABSTRACT FROM AUTHOR]

Correction for ‘Synthesis and structural characterization of metal complexes with macrocyclic tetracarbene ligands’ by Fan Fei et al., New J. Chem., 2017, 41, 13442–13453. [ABSTRACT FROM AUTHOR]

An "AND" logic gate-based NIR fluorescent probe Si-NH2-Glu was developed based on novel meso-amine Si-Rhodamine, which combined γ-glutamyl transpeptidase and pH dual-responsive sites. The features of Si-NH2-Glu enable it to be applied in orthotopic tumor imaging and fluorescence-guided surgery. [ABSTRACT FROM AUTHOR]

Four macrocyclic hybrid salts with different numbers of benzimidazolium and amine units, [H2L][PF6]2 (L = L1, L2, L3) and [H4L4][PF6]4, have been employed as the heterocyclic carbene (NHC) precursors toward new Ag(i)– and Au(i)–NHC complexes. Three trinuclear and one tetranuclear Ag(i) complexes 1–4 have been obtained from the reactions of the NHC precursors and Ag2O in acetonitrile. Four dinuclear Au(i)–NHC complexes 5–8 have been prepared by reacting the NHC precursors and AuCl(SMe2) in the presence of NaOAc in DMF. The molecular structures of all the complexes are established by single-crystal X-ray diffraction studies. The metal ions in the Ag(i) complexes 1–3 and the Au(i) complexes 5–7 are coordinated with two macrocyclic NHC ligands to form a sandwiched structure. In contrast, a trinuclear Ag3 core is located in the cavity of one macrocyclic ligand in [Ag3(L4)][PF6]3 (4). The photoluminescence properties of Au(i) complexes 5–8 have also been investigated. [ABSTRACT FROM AUTHOR]

A general strategy for the hydroalkylation of vinyl ketones using ethers catalyzed by an iron catalyst is described. This catalytic method permits direct transformation of easily accessible and abundant precursors into highly substituted, structurally diverse and functionally concentrated products. [ABSTRACT FROM AUTHOR]