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In this study, we designed and synthesized three conformation-adaptive Pd2L4- and Pd3L6-type coordination cages based on three dihydrophenazine-based ligands with different lengths. Interestingly, the shorter ligands L1 and L2 self-assembled into Pd2L4-type coordination cages while the longer ligand L3 formed Pd3L6-type one, mainly driven by the anion template effect. All coordination cages were confirmed through single-crystal X-ray diffraction, and their structural conformations underwent great changes compared with those of their corresponding ligands. Moreover, the conformational changes also significantly affected their photophysical and electrochemical properties which were distinct from their parent ligands. [ABSTRACT FROM AUTHOR]

By simple ligand exchange of the cationic transition-metal complexes [(Cp*)M(acetone)3](OTf)2 (Cp*=pentamethylcyclopentadienyl and M=Ir or Rh) with pillar[5]arene, mono- and polynuclear pillar[5]arenes, a new class of metalated host molecules, is prepared. Single-crystal X-ray analysis shows that the charged transition-metal cations are directly bound to the outer π-surface of aromatic rings of pillar[5]arene. One of the triflate anions is deeply embedded within the cavity of the trinuclear pillar[5]arenes, which is different to the host-guest behavior of most pillar[5]arenes. DFT calculation of the electrostatic potential revealed that the metalated pillar[5]arenes featured an electron-deficient cavity due to the presence of the electron-withdrawing transition metals, thus allowing encapsulation of electron-rich guests mainly driven by anion-π interactions. [ABSTRACT FROM AUTHOR]

The combination of phosphine-ligated Pd catalysis and phosphenium(v) Lewis acid catalysis has been developed for the carbonylative Sonogashira reaction using phosphino-phosphenium salts (L1–L4) as bifunctional ligands, in which the Lewis acidic phosphenium(v) cations can form secondary bonds with O atoms (in C=O) to cooperatively stabilize Pd–acyl intermediates. [ABSTRACT FROM AUTHOR]

A simple, new type of chiral sulfinamide monophosphines, the so-called Ming-Phos ligands, is reported; these ligands could be easily prepared from inexpensive and commercially available starting materials. The Ming-Phos ligands performed well in the enantioselective gold-catalyzed cycloaddition reaction of 2-(1-alkynyl)-alk-2-en-1-ones with nitrones. Both enantiomers of the products could be obtained in good yields and with excellent diastereo- and enantioselectivity through transformations that were catalyzed by gold complexes derived from two diastereomers of Ming-Phos ligand M5 (Ar=1-naphthyl). [ABSTRACT FROM AUTHOR]

Abstract: A large family of crystalline compounds with silver acetylenediide (Ag2C2) as a component have been synthesized and characterized. In most cases the C2 2− species is enclosed in a silver(I) polyhedron of 6–10 vertices, which may be symbolized as C2@Ag n (n =6–10). In the present review, emphasis is laid on our systematic studies in the controlled generation and supramolecular assembly of C2@Ag n polyhedra to form discrete molecules and higher-dimensional aggregates with the aid of co-existing anions and ancillary ligands. [Copyright &y& Elsevier]

Correction for ‘Bifunctional ligands in combination with phosphines and Lewis acidic phosphoniums for the carbonylative Sonogashira reaction’ by Chen Tan et al., Chem. Commun., 2015, 51, 10871–10874. [ABSTRACT FROM AUTHOR]

Highly selective anti-Markovnikov alkoxycarbonylation of alkenes over L2 -Pd(OAc) 2 catalytic system under mild conditions. [Display omitted] • Highly selective anti-Markovnikov alkoxycarbonylation of alkenes under mild conditions. • Bis-P,O-hybrid ligand of L2 with flexible meta - positioned dimethylene-phenyl backbone serving as a tripodal P,P,O-pincer with hemilability. • L2 conferring to Pd-catalyst the high activity and excellent regioselectivity. • L2 facilitating the formation and stability of Pd H active species. A series of bis-P,O-hybrid ligands (L1–L4) were synthesized and characterized. The crystal structures demonstrated that the ligand of L2 , 1,4-bis((2-(diphenylphosphaneyl)phenoxy)methyl)benzene, not only acted as a typical trans -positioned diphosphine as observed in the complexes Pd(L2)(OAc) 2 and Pd(L2)Cl 2 , but also potentially as a P,P,O-tripodal pincer. As a result, under mild conditions (80 °C, 0.5–3.0 MPa), L2 enabled Pd(OAc) 2 to exhibit remarkable performance in terms of high activity and excellent regioselectivity (l / b > 97/3) in the alkoxycarbonylation of vinyl arenes with the isolated yields of 57–91 %. [ABSTRACT FROM AUTHOR]

Five new metal-organic frameworks (MOFs) with 5-(4-carboxybenzoylamino)-isophthalic acid (H3L), namely, [Cd9L6(DMA)6]·4DMA (1), [Cd3L2(H2O)9]·4H2O (2), [LaL(H2O)4]·2H2O (3), [CeL(H2O)4]·H2O (4) and [Tb(HL)(H2L)(H2O)3]·5H2O (5) (DMA=N,N-dimethylacetamide), have been synthesized. Complex 1 shows a three-dimensional architecture generated from linkage of Cd–O chains via L3− ligands. Minor variations in synthetic conditions of 1 afforded 2, which features an interesting 2D→3D catenation architecture containing helical chains. Complexes 3 and 4 are isostructural and each feature a two-dimensional architecture constructed from the linkage of L3− with Ln3+. Complex 5 displays a chain-like structure, of which the most interesting feature is the existence of free carboxylic acid (–COOH) group which may confer unique functionality. Moreover, the investigations of the thermal stability, powder X-ray diffractions and solid-state photoluminescent properties for these crystalline materials have been carried out. [ABSTRACT FROM AUTHOR]

Abstract: The combination of divalent zinc ions, 4-(4-carboxybenzamido)benzoic acid and exo-bidendate bipyridine ligands gave rise to a series of new MOFs: [ZnL(bipy)]·DMF·H2O (1), [ZnL(bpe)]·1.5H2O (2), [ZnL(bpa)]·4H2O (3) and [ZnL(bpp)]·1.75H2O (4) (MOF=metal-organic framework, bipy=4,4′-bipyridine, bpe=trans-1,2-bis(4-pyridyl)ethylene, bpa=1,2-bis(4-pyridinyl)ethane, bpp=1,3-bis(4-pyridinyl)propane, H2L=4,4′-(carbonylimino)dibenzoic acid). Fine tune over the topology of the MOFs was achieved via systematically varying the geometric length of the second ligating bipyridine ligands. Single-crystal X-ray analysis reveals that complex 1 has a triply interpenetrated three-dimensional (3D) framework with elongated primitive cubic topology, whereas isostructural complexes 2 and 3 each possesses a 6-fold interpenetrated diamondiod 3D framework. Further expansion of the length of the bipyridine ligand to bpp leads to the formation of 4, which features an interesting entangled architecture of 2D→3D parallel polycatenation. In addition, the thermogravimetric analyses and solid-state photoluminescent properties of the selected complexes are investigated. [Copyright &y& Elsevier]

The incorporation of –PPh 2 group in the parent molecule of 1-(thiazol-2′-yl)-imidazole afforded the hybrid P,S,N-ligands of 1 and 2 respectively. The former was quarternized by MeOTf to give the ionic hybrid P,S-ligand of 1′ . The single crystal X-ray diffraction analyses of the corresponding mono-nuclear Au(I)-complexes of 1A and 2A indicate that the Au(I)-centered vectors in each are in a slightly distorted linear configuration, in which Au(I) center is diagonally coordinated by one Cl − and one phosphine without the coordinating interaction to N (or S)-donors. When the mono-nuclear Au(I)-complexes of 1A , 1′A , and 2A were employed as the catalysts for hydrations of phenylacetylene in aqueous-methanol media with the involvement of AgOTf and H 2 SO 4 , the reactions over 1A proceeded selectively according to Markovnikov's rule with much high yields of acetophenone than those over 1′A and 2A , indicating that the available additional S-, and N-donors in 1A with less steric hindrance synergetically protected the active Au(I)-complex species against deactivation during the catalytic cycle. [ABSTRACT FROM AUTHOR]

The ionic hybrid P,N-ligands of 1 and 2 have been synthesized as one type of unconventional tertiary phosphines with the advantages of both the π-accepting ligands and the hemilabile ligands. The corresponding ionic Rh(I)-complexes of 1A and 2A proved to be more efficient catalysts for hydroformylation of 1-octene over isomerization than the traditional Rh I (acac)(CO)(PPh 3 ), due to the π-backdonation interaction in Rh → P linkage and the hemilabile ligation of N,P-coordinating sites to Rh-center. The in situ high-pressure FT-IR analysis indicated that: (1) the formation and lifetime of the active Rh H species (2047 cm −1 ) derived from 1A are facilitated by the presence of ligand 1 ; (2) the formation of the active Rh H species is depressed without the aid of the P,N-hemilabile ligation; and (3) the active Rh H species derived from Rh I (acac)(CO)(PPh 3 ) is unstable and susceptible to the formation of the inactive carbonyl-bridged Rh-dimer. [ABSTRACT FROM AUTHOR]

Abstract: 4,4′,4″-[1,3,5-Benzenetriyltris(carbonylimino)]trisbenzoic acid (H3L), a C 3-symmetric ligand, was found to self-assemble into an interesting core-rosette structure driven by intermolecular hydrogen-bonding interactions. Reactions of this ligand with Zn2+, Co2+ and Cd2+ under solvothermal conditions resulted in the formation of four new coordination polymers with interesting structural motifs: [Zn2(L)(OH)(H2O)(DMF)]·DMF·H2O (1), [Co3(L)2(DMF)(H2O)]·DMF·3CH3OH (2), [Co1.5(L)(H2O)(DMF)]·DMF (3), and [Cd1.5(L)(H2O)(DMF)]·DMF (4). Single-crystal structural analysis revealed that complex 1 exhibits a rare example of twofold interpenetrating two-dimensional CdI2-type structure with tetranuclear Zn4(μ 3-OH)2(COO)6(H2O)(DMF) serving as secondary building unit (SBU), whereas in 2, the μ3 -oxo-tricobalt basic carboxylate SBUs are connected by L3− ligands, leading to a twofold interpenetrating three-dimensional (3,6)-net framework. The isomorphous complexes 3 and 4 each has a (4,4)-grid layered architecture in which the SBU is a linear Co3/Cd3 cluster. The four coordination polymers were all further characterized by IR, thermogravimetric and powder X-ray diffraction (PXRD). [Copyright &y& Elsevier]