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Triphenylamine (TPA) derivatives have been widely used as useful building blocks for diverse functional materials because of their excellent redox activity. Most of the molecular structures of TPA-based organic functional materials contain 4-anisyl groups, which on one hand could reduce their oxidation potential and on the other hand significantly delocalize the spin density of the resultant TPA radical cation species and enhance their stability. However, molecular-level investigation of the redox behavior of triphenylamines consisting of 4-anisyl group and the electronic structures of their radical cation species has not been reported in the literature. Herein, we design a series of triphenylamines consisting of one, two, or three 3,5-di-tert-butyl-4-anisyl groups and investigate their redox behaviors and corresponding radical cation species. We disclose that the resonance hybrid and steric protection could both contribute to the stability of triphenylamine radical cations. Moreover, further oxidation leads to an unexpected oxidative demethylation. The findings in this work may reveal new insights for the understanding of the unique redox properties of 4-anisyl substituted triphenylamines.

A series of triphenylamine (TPA) derivatives with various substituent groups were prepared and showed different absorption and fluorescence characteristics due to the substituent effect. On account of the existence of pyridine units, these TPA derivatives exhibited acid-induced tunable multicolor fluorescence emission including white light emission. In addition, acid-induced fluorescence regulation of these compounds has been also realized in the solid state, which enable them to be successfully constructed the stimuli-responsive fluorescent films and fluorescent inks for inkjet printing.

An unexpected bistricyclic aromatic ene AF was synthesized in a tin(II) chloride-mediated reductive aromatization reaction. The obtained AF showed a highly overcrowded structural conformation as revealed by X-ray crystallography. Interestingly, AF exhibited reversible high-contrast mechanochromism and thermochromism between pale and red color. The obvious chromism is likely ascribed to the conformation transformation and trace amount of diradical species formation upon stimulus.

The complexation of IrCl3⋅3H2O with the electron-deficient phosphines (L1-L6) respectively afforded a bi-functional catalyst possessing the dual functions of transition metal complex (IrIII-P) and IrIII-Lewis acid for tandem hydroformylation-acetalization of olefins. The best result was obtained over L5-based IrCl3⋅3H2O catalytic system which corresponded to 97% conversion of 1-hexene along with 92% selectivity to the target acetals free of any additive. The crystal structure of the novel IrIII-complex of IrIII-L4 indicated that the electron-deficient nature of the involved phosphine warranted Ir-center in +3 valence state without reduction, which served as the Lewis acid catalyst for the subsequent acetalization of the aldehydes as well. Moreover, as an ionic phosphine, L6-based IrCl3⋅3H2O system immobilized in RTIL of [Bmim]PF6 could be recycled for 6 runs without the obvious activity loss or metal leaching.

A series of novel multi (bi-/tri-/tetra-)-dentate phosphines with good robustness against water and oxygen were synthesized and fully characterized. It was found that the developed ionic tri-dentate phosphine (L2′) enabled Pd-catalyzed alkoxycarbonylation of alkynes most efficiently while H2O was used as an additive instead of acid. As for L2′, its unique steric configuration with two types of potential P-P chelation modes (P⋯P distance of 4.31 A and 4.36 A respectively) to Pd-centre rendered the corresponding Pd-catalyst high activity and good stability for alkoxycarbonylation of alkynes. The in situ FT-IR analysis also verified that the formation and stability of Pd–H active species were greatly facilitated with the presence of L2′ as well as H2O additive. In addition, as an ionic phosphine, L2′ based PdCl2(MeCN)2 system immobilized in RTIL of [Bmim]NTf2 could be recycled for 7 runs without obvious activity loss or metal leaching.

The formation and growth of natural objects are affected by the available space and materials. A regular hexagon is one of three regular polygons that can overlap without a plane. Among these three regular polygons (equilateral triangle, regular quadrilateral, and regular hexagon), the regular hexagon occupies the largest area with the smallest amount of material. The construction of supramolecular hexagonal architectures has been of great interest within supramolecular chemistry and materials science. Since supramolecular self-assembly enables the preparation of highly complex supramolecular systems from relatively simple building blocks, various metallosupramolecular hexagonal architectures have been successfully constructed under mild conditions by employing facile coordination-driven self-assembly strategy, and some of the architectures have exhibited wide ranges of applications in the fields of catalysis, electrochemistry, photochemistry, molecular sensing, etc. This review summarizes recent advances in the field of supramolecular hexagonal metallacycles. The design, self-assembly, and applications of various supramolecular hexagonal metallacycles, especially those incorporating functional moieties, will be discussed.

Castor oil (CSO)-derived polyurethanes (PUs) are limited by the low mechanical performance and non-reprocessability arisen from their permanently crosslinked structures with high crosslink density and flexible network backbone. In this study, we report malleable polyurethane networks prepared from CSO and hexamethylene diisocyanate with vanillin derived Schiff base (VSB) as a multifunctional monomer. On one hand, VSB with multiple rigid benzene rings and two hydroxyl groups works as a structure modifier to regulate network stiffness and crosslink density of the PUs, which allows us to tailor their mechanical properties over a broad range from soft to tough and hard depending on the content of VSB. On the other hand, VSB with dynamic imine bonds provides the PUs with vitrimeric properties including malleability, thermal processability, and recyclability via network topological rearrangement as a result of imine exchange reaction at elevated temperatures. Consequently, we achieved malleable, processable, and recyclable CSO-derived PU vitrimers with tunable mechanical properties (from elastomer to tough and hard plastics), which would improve the viability and sustainability of CSO-based PUs.

Two isostructural series of four lanthanide coordination complexes have been synthesized by hydrothermal method with anthraquinone-1,8-disulfonate as the anionic ligand. The complexes also comprise K+ ions that participate into coordination to form bimetallic complexes. The ligands in these complexes chelate to either lanthanide or K+ ions, and in some circumstance bridge the ions as well. Besides inter-/intra- molecular hydrogen bonding between the sulfonate groups and water molecules, π-π stacking interactions also contribute to the stabilization of the crystal packing. Investigation of the catalytic properties of the complexes indicated that they were able to promote the oxidation reaction of thioethers into sulfoxides, in which the Er3+ coordination complex exhibited the best catalytic efficiency over a wide range of substrates.

Four isostructural lanthanide coordination complexes based on 3,7-diamino-9,10-anthraquinone-2,6-disulfonate (dianionic, L) have been synthesized by hydrothermal method, namely [Er(L)(H2O)6]•[Er(H2O)8]•2L•8H2O (Er-L), [Tm(L)(H2O)6]•[Tm(H2O)8]•2L•8.5H2O (Tm-L), [Yb(L)(H2O)6]•[Yb(H2O)8]•2L•9H2O (Yb-L), [Lu(L)(H2O)6]•[Lu(H2O)8]•2L•9H2O (Lu-L). Single-crystal X-ray analysis reveals the existence of both coordinated and free ligand L in the crystal structure. Versatile sulfonate groups on these distinct L ligands, together with very rich coordinated and lattice water molecules, form a lot of hydrogen-bonding motifs that contribute to the stabilization of the crystal packing. It is interesting that the ligands stack into columns through strong π-π interactions and the centroid-centroid distances are between 3.281 and 3.331 A. These ligands are stacked in an alternate off-set mode to avoid the steric hindrance between the bulky sulfonate groups, generating a repeated structural unit involving six stacked ligands. These lanthanide complexes proved to be good heterogeneous photocatalyst for promoting the visible-light driving photooxidation reactions of diarylacetylenes and thioethers. The Er-L complex exhibited the best catalytic activity and showed good catalytic efficiency over a wide range of substrates for both reaction systems. The Er-L photocatalyst can be easily isolated by simple filtration as crystalline material upon completion of the photooxidation reaction without structure change, and can be recycled for at least five catalytic cycles with persistent catalytic efficiency without any need of activation or regeneration. This family of lanthanide complexes represent a category of promising heterogeneous photocatalysts in terms of green chemistry, with the potential of promoting organic transformations highly efficiently under the irradiation of visible light.

The first conjugate addition of α-isocyanoacetates with in situ generated azoalkenes from α-halogeno hydrazones in the presence of Cs2CO3 has been developed. The reaction condition was suitable to various α-aryl substituted isocyanoacetates as well as aryl and alkyl-substituted α-halogeno hydrazones, affording the corresponding products in good to high yields. The adducts can be easily transformed into biologically attractive 1,4-dihydropyrimidine derivatives via an intramolecular cyclization by treating with AgOAc. The one-pot conjugate addition/intramolecular cyclization has also been investigated to furnish the formal [3 + 3] cycloadduct, 1,4-dihydropyrimidine derivatives.

The complex of Au-L1 containing imidazolyl ring and the phosphine-ligated-Au moiety was synthesized and applied as the efficient bi-functional catalyst for the one-pot sequential condensation/annulation reaction for the synthesis of pyridine derivatives. It was found that, as for Au-L1, the involved imidazolyl group acted as a Lewis base to catalyze the condensation of carbonyl compounds with propargylamine to form the imino intermediate, and the involved Au+-complex species with alkynophilicity corresponded to the subsequent activation of imino-tailed alkynyl to afford dehydropyridine intermediate. The latter proceeded auto-oxidation reaction to afford the pyridine derivatives. The observed sequential catalysis over Au-L1 proved more efficient than that over the mechanical mixtures of the Au-complex (Au-L2) and N-methylimidazole, because the free N-methylimidazole as an N-containing donor competed with the alkyne substrate to coordinate to Au-center. Moreover, Au-L1 exhibited good generality to a wide range of the substrates for the synthesis of 2,3-fused pyridine derivatives and 2-aryl(heteroaryl)-substituted pyridines.

The role of auxiliary solvents in the formation of MOFs has been investigated for a series of Mn II -based framework systems. Reactions of 4,4′,4″-nitrilotribenzoic acid (H 3 L) with Mn II through varying auxiliary solvents of the medium resulted in the formation of diversified multinuclear Mn II subunits in four new coordination polymers: [Mn 3 (L)(HCOO) 3 (DEF) 3 ] ( 1 ), [Mn 3 (L) 2 (EtOH) 2 ]·DMF ( 2 ), [Mn 5 (L) 4 (H 2 O) 2 ]·2(H 2 NMe 2 ) + ·4DMF·2H 2 O ( 3 ), and [Mn 3 (L) 2 (py) 4 (H 2 O)]·H 2 O ( 4 ) (H 3 L=4,4′,4′-nitrilotribenzoic acid, DMF=dimethylformamide, DEF=N,N-diethylformamide, py=pyridine). These four compounds were fully characterized by single-crystal X-ray diffraction, showing interesting SBUs variations. For compound 1 , it displays a (3,6)-connected kgd net with wheel [Mn 6 ] cluster serving as SBU, whereas in 2 , the sequence of Mn 3 (COO) 9 (EtOH) 2 is repeated by inversion centers located between Mn1 and Mn3 to form an infinite Mn-carboxylate chain, which are further interlinked by L 3− ligands to form a 3D architecture. In 3 , the pentanuclear Mn 5 (CO 2 ) 12 clusters are interlinked to form a layer, which are further pillared by L 3− to generate a 3D network. Compound 4 has a (3,6)-connected network in which the SBU is a linear trimeric Mn 3 (COO) 6 (py) 4 (H 2 O) cluster. In addition, the thermal stabilities, X-ray powder diffraction of all the compounds were studied, photoluminescence behaviors of compounds 1 , 3 and 4 are discussed.

A new metal–organic polyhedron Cu-MOP with octahedral geometry was constructed by 2,8-dibenzothiophenedicarboxylic acid and dicopper paddlewheel. Cu-MOP exhibited H2 and CO2 sorption behavior. Furthermore, Cu-MOP revealed reductive properties towards TCNQ, DDQ, CR and MB due to the electron-donating nature of DBT ligand.

The neutral palladium(II) complex bis-[1-(5’-diphenylphosphinothiazol-2’-yl)-imidazolyl] dichloropalladium(II) (1A) ligated by thiazolylimidazolyl-based phosphine (L1) in which thiazolylimidazolyl acted as an S- and N-donor provider with weak coordinating nature, and the ionic complex bis-[1-(5’-diphenylphosphinothiazol-2’-yl)-3-methylimidazolium] dichloropalladium(II) trifluoromethanesulfonate (2A) ligated by thiazolylimidazolium-based phosphine (L2) after quaternization of L1 using methyl trifluoromethanesulphonate were synthesized. It was found that the introduced positive charges and strong electron-withdrawing effect in 2A not only led to changes in the configuration and structural stability of the complex, but also lowered its catalytic performance in carbonylative Sonogashira reactions. These effects reveal the important role of the N-donor in 1A. In addition, as an ionic palladium complex, 2A combined with the room-temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate could be recycled eight times as the catalyst in carbonylative Sonogashira reactions without detectable metal leaching.

Based on a novel C3 symmetric tripodal ligand 1,1′,1′′-[(2,4,6-trimethyl-1,3,5-benzenetriyl)tris(methylene)]tris[2(1H)-pyridinone], eight isostructural lanthanide coordination complexes have been constructed. The one-dimensional ladder-like chain structures in these complexes are packed together through the interaction of hydrogen bonding and π-π stacking, leading to the formation of a three-dimensional structure with one-dimensional channels. A systematic study on Ln-O bond lengths in this family of complexes revealed that Ln-O distances exhibited a trend according to the lanthanide contraction. And the torsion angles that define the ligand conformation are different for the pyridone groups on distinct side of the plane of the central phenyl ring. Selected complex from the family shows highly selective and sensitive fluorescence quenching by Fe3+ ion, which is not affected by other common metal ions. The Stern–Volmer curve regarding the fluorescence quenching of Fe3+ toward the complex exhibits perfect linearity for a variety of concentrations, demonstrating the complex to be a good candidate as highly selective, efficient, and quantitative fluorescent probe for Fe3+.

Biobased polymers prepared from vegetable oils such as epoxidized soybean oil (ESO) cannot be reprocessed or recycled due to the permanent crosslink structure. Herein, we report ESO derived vitrimers (ESOVs) synthesized by catalyst-free curing of ESO with 4, 4′-dithiodiphenylamine (APD) as a curing agent. The crosslink density controlled by curing time affect the mechanical properties of ESOV strongly. The tensile strength increased and elongation at break decreased gradually with increasing crosslink density of ESOV. The dynamic disulfide linkages of APD imparted the ESOV with excellent reprocessability and weldability via network topology rearrangement as a result of exchange reaction of disulfide bonds. The mechanical properties, gel fraction and chemical structure of ESOV almost remained unchanged after repeatedly cutting and compression molding for several times. The mechanical properties of ESOV were also recovered completely when two broken parts of ESOV were welded together. This study provides a facile and promising strategy to design novel functional materials from sustainable vegetable oils.

A C3-symmetric tripodal ligand, 1,1′,1″-(nitrilotri-2,1-ethanediyl)tris-2(1H)-pyridinone (ntetp), has been designed and synthesized. Two families of isostructural rare earth coordination complexes have therefore been constructed based on this ligand, namely [M(ntetp)(NO3)3]n [M = Y(1), La(2), Ce(3), Pr(4), Sm(5), Gd(6), Dy(7), Ho(8)] and [M(ntetp)Cl3]n [M = Tb(9), Er(10), Yb(11), Lu(12)]. Single-crystal analyses reveal that both series of complexes bear one-dimensional chain structures, with the metal centers taking nine-coordinate geometry in 1–8 and distorted octahedral geometry in 9–12. Solutions of the selected representative complexes 1 and 10 show highly selective fluorescent enhancement toward Fe3+ ion, comparing to non-significant response toward Ca2+, Co2+, Zn2+, Cr3+, Mn2+, Ni2+, Cu2+, Cd2+, Li+, Na+, Al3+, K+, Ba2+ and Mg2+ ions. Also, the fluorescent enhancement induced by Fe3+ ion is not affected by the above-mentioned ions, demonstrating promising capabilities of complexes 1 and 10 as “turn-on” fluorescent probe.

The effect of positive charges in the diphosphino-imidazolium salts of L2 was investigated in terms of coordinating character, structures of corresponding Ir-complexes and catalysis for hydroformylation. It was found that the involved positive charges exhibited strong electron-withdrawing effect on the neighbored phosphine fragment, rendering L2 more π -acceptor ability than the corresponding neutral counterpart of L1 . Consequently, the changed coordinating ability of L1 and L2 led to the variety in the structures and components for the Ir-complexes ( Ir-L1a , Ir-L1b , Ir-L2a , and Ir-L2b ). The complexation of L2 with Ir(acac)(CO) 2 led to a novel five-coordinate Ir(II)-complex of Ir-L2a chelated by a PCC (phosphine–carboanion–carbene) pincer in tripodal mode, whereas the complexation of L1 with Ir(acac)(CO) 2 led to a four-coordinate square-planar Ir(I)-complex of Ir-L1a chelated by a PCP (phosphine–carboanion–phosphine) pincer. In addition, the different catalytic performances of these Ir-complexes ligated by L1 and L2 for hydroformylation of olefins were investigated.

Two kinds of novel zwitterionic phosphines of L1 and L2 have been synthesized in which the sulfonate groups (–SO3–) are incorporated to render them amphiphilic. Both of them are strong π-acceptor ligands in which the positive-charged imidazoliums with intensive electron-withdrawing effect are vicinal to the coordinating phosphorous atoms. The amino-group of piperidyl is additionally incorporated in L2 to make it behave as a hybrid ligand with potential hemilability. The comparison of the ligands of L1 and L2 in Rh-catalyzed hydroformylation of styrene (and its derivatives) and the effect of water on their behaviors were discussed. Without the involvement of water, the catalytic system of Rh(acac)(CO)2-L2 exhibited lower activity than that of Rh(acac)(CO)2-L1 under the same conditions. However, the dramatic promotion effect of water as a suspension was observed especially for Rh(acac)(CO)2-L2 system with TOF spurred up from 195 to 470 h−1. The corresponding in situ high pressure FT-IR spectral information showed that the presence of water in Rh(acac)(CO)2-L2 system greatly facilitated the formation and stability of the active Rh–H species (νRh-H, 2047 cm−1), which was in charge of the efficient hydroformylation of styrene and its derivatives.

4,4′,4″-nitrilotribenzoic acid (H3L), a C3-symmetric ligand, was found to self-assemble into two polymorphs driven by intermolecular hydrogen-bonding interactions. Reactions of this ligand with Zn2+ under solvothermal conditions resulted in four new coordination polymers bearing interesting structural motifs: [Zn2(L)2(py)2]·2(H2NMe2)+·DMF·2H2O (1), [Zn2(L)(H2L)(bipy)]·1.5H2O·Guest (2), [Zn2(L)2(bipy)]·2(H2NMe2)+·2DMF (3), and [Zn3(L)2(bpa)]·2H2O·Guest (4) (H3L=4,4′,4′′-nitrilotribenzoic acid, DMF=dimethylformamide, py=pyridine, bipy=4,4′-bipyridine, bpa=1,2-bis(4-pyridyl)diazene). Single-crystal structural analysis revealed that compound 1 exhibits a rare example of twofold interpenetrating anionic 3D (3,3)-net framework containing helical channels, whereas in 2, the 3D pillar-layer structure generated from bipy-pillared Zn2(L)(H2L) layer is further reinforced by intermolecular hydrogen bonding among pairs of free –COOH units. Compound 3 shows an interesting entangled architecture of 2D→3D parallel polycatenation consisting five-coordinated Zn2+ ions. Compound 4 displays a 3D pillar-layer framework with trimeric Zn3(CO2)6 serving as secondary building unit (SBU). The syntheses, structures, thermal stabilities, powder X-ray diffractions and solid-state photoluminescence properties for these crystalline materials have been carried out. In addition, supramolecular assembly of H3L under solvothermal conditions will also be addressed.

The neutral diphosphine of 1 and the corresponding ionic diphosphine of 2 after quaternization 1 by MeOTf were prepared and investigated as the wide bite angle and bulky steric ligands to control the regioselectivity in Rh(acac)(CO)2-catalyzed hydroformylation of 1-octene. As for 2, due to the electrostatic repulsive force of the two positive charges, the involved two-PPh2 were located in trans-position with the relatively longer P1…P2 distance [8.0231(11) A] to prefer to aa-site coordination in trigonal bipyramid H(alkene)Rh(CO)(P–P) intermediate, which renders less bulky steric hindrance for the regioselectivity to linear aldehyde as a result of low L/B ratio of 1.9. Due to the strong electron-withdrawing effect from the positive-charged imidazolium rings on the neighbored P-atoms, 2 with strong π-acceptor ability can develop π-backdonation interaction between Rh and P linkage to favor the dissociation of CO ligand and facilitate the selectivity to nonanals. In contrast, 1 with no electrostatic repulsive effect and less steric hindrance, the two-PPh2 were able to be conveniently located in cis-position with the relatively shorter P1…P2 distance [P1…P2, 6.2096(10) A], which corresponded to the preferential linear regioselectivity with L/B = 7.1. The in situ high pressure spectroscopy analysis indicated that the involvement of 1 in Rh(acac)(CO)2-catalyzed hydroformylation of 1-octene could greatly facilitate the formation and stability of the active Rh–H species (ν2047 cm−1).

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.

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.

A series of ionic Au(I)-complexes ligated by the phosphine-functionalized ionic liquids were synthesized and characterized, which are composed of the Au(I)-complex cation and the counteranion of OTf−, AuCl4−, or PF6−, respectively. The single crystal X-ray diffraction analyses show that the Au(I)-centered vector in 1A, 1B, 2A, 3A, and 4A all possess the slightly twisted linear geometry, and in each individual the Au(I)-center is coordinated by one chlorine and one imidazolium-based phosphine. The aggregation of 1B in acetone can lead to the formation of the trinuclear Au(I)-complex of 1C due to the aurophilic Au(I)–Au(I) interaction, the electrostatic attraction, and the steric preference. When these ionic Au-complexes were employed as precatalysts for hydration of phenylacetylene in aqueous-methanol media, the reaction proceeded selectively according to Markovnikov's rule with moderate to high yields of acetophenone. The highest activities were achieved over 2A with hydrophobic PF6− as the counteranion and the trinuclear 1C under mild conditions (75 °C, 2 h), in conjunction with the additive of proton acid H2SO4. The ion-pair effect on the catalytic performance of the corresponding Au(I)-complexes, coming from the phosphine-ligated cations and the counteranions, were investigated.

A series of phosphino-imidazolium salts ( 1 – 4 ), which are composed of the phosphine-incorporated imidazolium cations and the corresponding counter-anions of PF 6 − , TfO − , and BF 4 − , are used in Rh-catalyzed hydroformylation. It was found that when the ionic Rh(III)-complex ( 1A , [Rh III Cl 4 ( L ) 2 ]PF 6 , L = 1-butyl-2-diphenylphosphino-3-methylimidazolium) was used as the pre-catalyst for hydroformylation of 1-octene, its inert catalytic activity could be efficiently tailored by the ion-pair synergetic effect of ligand 1–4 in water suspension. The single crystal structures of 1 , 2 , and 4 indicate that the hydrogen bonding network is developed between the cation and anion of ion-pairs 1 and 4 , but is completely non-inexistent in 2 .

Using vacuum ultraviolet photons produced by synchrotron radiation and reflection time-of-flight mass spectrometer, dissociative photoionization of isooctane was measured in the photon energy region of 9.7–15.6 eV under ultrasonic molecular beam. Then the dissociative ionization products at different photon energies were obtained. By measuring the photoionization efficiency curves, the appearance potentials of the dominative ion fragments and the vertical ionization energy of isooctane were determined. In addition, combining with G3 calculations we obtained the structure and energy of the parent, neutral and ion fragments. By comparing the experimental measurements with the theoretical calculations, the dissociative photoionization channels of isooctane were elucidated, and formation enthalpies of the fragmented ions and the dissociation energy of the parent ion were obtained.

A novel ionic complex with insensitivity to moisture and air, bis-[1-butyl-2-diphenylphosphanyl-3-methylimidazolium]tetrachloridorhodium(III) hexafluorophosphate ( 1A ), has been synthesized and fully characterized. The single-crystal X-ray diffraction analysis shows that 1A is composed of the Rh(III)-complex cation and the counter-anion of PF 6 − . The complex cation has highly symmetrical Rh III -centered octahedron geometry with four Cl atoms in the equatorial plane and two imidazolium-substituted phosphine ligands in the axial position. The catalytic performance of 1A , which could be tailored by the ligands and the solvents, was investigated toward the biphasic hydroformylation of 1-octene. It was found that the presence of the hemilabile hybrid P,N-ligand of 3 (1-(2′-piperid-1′-yl-ethyl)-2-diphenylphosphino-3-methylimidazolium hexafluorophosphate), as a kind of ligand-functionalized ionic liquids (ILs), could dramatically spur the catalytic activity of 1A . The use of the RTIL of [PEmim]BF 4 (1-(2′-piperid-1′-yl-ethyl)-3-methylimidazolium tetrafluoroborate) as the solvent not only fulfilled the efficient biphasic hydroformylation of 1-octene, but also guaranteed the successful recovery and recycling of the ionic compositions of 1A and 3 .

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.

The synthesis of oxacalix[2]terphenylene[2]aromatics with enlarged macrocyclic holes by cyclooligomerization reaction of 5′-tert-butyl-(1,1′:3′,1″-terphenyl)-3,3″-diol 1 with electron-deficient dihalogenated benzene and azaheterocycles is described. The structures of the macrocycles were characterized by NMR, HRMS spectroscopic and X-ray diffraction techniques. Single crystal X-ray analysis revealed that the terphenyl-3,3″-dioxo unit incorporated in the oxacalix[4]aromatics scaffold can adopt all three possible conformations (I, II, III). The cis-conformational terphenyl-3,3″-dioxo (I and II) derived oxacalix[4]aromatics were found to adopt both chair and boat conformations, resulted in creation of molecular cavities capable of hosting solvent molecules of chloroform. The trans-conformational terphenyl-3,3″-dioxo (III) derived oxacalix[4]aromatics, however, adopt a twisted chair conformation with a narrow void space incapable of hosting any guest molecules.

Assembly reactions of acylamide-containing dicarboxylate ligand 4,4′-(carbonylimino)dibenzoic acid (H2L) with corresponding divalent metal ions resulted in the formation of seven new coordination polymers, namely Cd(L)(H2O) (1), Zn(L)(H2O) (2), Zn5(L)2(OH)6 (3), [Ni(L)(H2O)2]·H2O (4), [Cd(L)(py)(H2O)]·(DMF)·(C6H5Cl) (5), [Cd(L)(py)2]·2CH3OH (6) and [Mn (HL)2(py)2]·2DMF (7). In complex 1, the double chains composed CdII and L2− are connected by interlayer Cd–O bonds to form a three-dimensional architecture. Complex 2 exhibits a three-dimensional supramolecular architecture extended by hydrogen bonds involving O–H⋯O and N–H⋯O types. Complex 3 displays a three-dimensional framework consisting of zinc-hydroxide layers and L2− pillars. Complex 4 is also a supramolecular three-dimensional network generated from linkage of Ni–O chains via versatile hydrogen bonds. Complex 5 exhibits an interdigitated network in which the cavities are occupied by guest DMF and C6H5Cl molecules. In complex 6, two-dimensional square-grid network was generated by linkage of Cd2 units with L2− ligands. Mono-depronated ligand presents in complex 7. The adjacent [Mn(py)(HL)] chains are arranged parallel to each other by forming hydrogen bonding between the acylamide groups and guest DMF molecules. The stability properties of 2, 3, 4, 6 and 7 have been presented. In addition, photoluminescence properties of complexes 2, 3, 5 and 6 are investigated.

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.

Several novel azacalix[4]aromatics constituting terphenylene units have been synthesized via sequential nucleophilic aromatic substitution reactions of 5′-t-butyl-(1,1′:3′,1″-terphenyl)-3,3″-diamine 9 and 5′-t-butyl-(1,1′:3′,1″-terphenyl)– 4,4″-diamine 11 with 1,5-difluoro-2,4-dinitrobenzene and cyanuric chloride, respectively. The bridging –NH– functions of the tetra-nitro substituted azacalix[2]arene[2]terphenylenes 1 and 2 have been transformed to the corresponding –N(CH3)– bridged azacalix[2]arene[2]terphenylenes 3 and 4 via N-alkylation. Single crystal X-ray analysis revealed that the terphenyl-3,3″-diamine derived azacalix[2]terphenylene[2]triazine 5 adopts a distorted chair conformation in the solid state, and the terphenyl-4,4″-diamine derived azacalix[2]terphenylene[2]triazine 6 was found to adopt a 1,3-alternate conformation.

4,4′,4″-[1,3,5-Benzenetriyltris(carbonylimino)]trisbenzoic acid (H3L), a C3-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(μ3-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).

A dual functional three-dimensional porous NbO-type metal–organic framework with inserted acylamide units was solvothermally synthesized, which exhibits large CO2-uptake capacity (160 cm3 g− 1 at 1 bar), high selectivity toward CO2/N2 (41.6 at 273 K) and satisfied catalytic activity in Knoevenagel condensation reaction.

Two pyrazine-containing macrocyclic polyazomethines 2 and 3 were synthesized by direct [2 + 2] and [3 + 3] condensation reactions between 2,2′-[pyrazine-2,3-diylbis(oxy)]dibenzaldehyde (1) and hydrazine. Both 2 and 3 were characterized by NMR, HRMS, and their structures were determined via X-ray crystal diffraction studies.

Reactions between [M 2 (dppm) 2 (NCMe) 2 ]X 2 [M = Ag, X = ClO 4 ; M = Cu, X = BF 4 ] and Ru(C CC CM)(dppe)Cp∗ [M = Ag, Cu; generated in situ from Ru(C CC CH)(dppe)Cp∗ and AgNO 3 or CuCl(PPh 3 ), respectively] afford the cationic mixed-metal cluster diynyl complexes [M 6 {μ 3 -C CC C[Ru(dppe)Cp∗]} 4 (μ-dppm) 2 ]X 2 , of which the structures were determined by single-crystal XRD studies. Electrochemical studies indicate that there is no interaction between the ruthenium centres. Reactions between [M 2 (μ-dppm) 2 (NCMe) 2 ](BF 4 ) 2 and Ru(C CC CM′)(dppe)Cp∗ (M,M′ = Cu, Ag) afforded a mixture of Ag 6− n Cu n clusters, as shown by ES-MS and crystallographic studies. Preliminary studies suggest that extensive disproportionation occurs in solution.

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

Five new silver(I) triple salts: (Ag 2 C 2 )(AgNO 3 ) 4 (AgL 1 ) 2 (L 1 H) 2 ( 1 ), (Ag 2 C 2 )(AgCF 3 CO 2 ) 2 (AgL 1 ) 2 (L 1 H) 1/2 ( 2 ), [(Ag 2 C 2 )(AgCF 3 CO 2 ) 4 (L 2 )(H 2 O)] · (L 2 H 2 ) ( 3 ), (Ag 2 C 2 )(AgNO 3 ) 3 (AgL 3 ) 2 ( 4 ), and [(Ag 2 C 2 )(AgCF 3 CO 2 ) 4 (AgL 3 ) 2 (H 2 O) 2 ] · H 2 O ( 5 ) (L 1 H = nicotinic acid, L 2 H = isonicotinic acid, L 3 H = 2-pyrazinecarboxylic acid) have been synthesized by the hydrothermal method. All five compounds contain polyhedral silver(I) cages each encapsulating an acetylenediide dianion, C 2 2 - . In 1 , C 2 @Ag 8 cages in the shape of bicapped trigonal prisms are interlinked by nitrate, L 1 , and L 1 H ligands into a three-dimensional architecture. In 2 , silver(I) columns generated from fusion of triangulated dodecahedra are linked by L 1 into a layer structure. Compound 3 provides a rare example of a (L 2 H 2 ) + -pillared three-dimensional structure via hydrogen bonding. In 4 , nitrate ligands together with L 3 link the C 2 @Ag 7 cages into a three-dimensional architecture. Compound 5 also exhibits a three-dimensional architecture generated from trifluoroacetate and L 3 -linked C 2 @Ag 8 cages.

The new silver(I) complexes (bpeH2 · 2H2O)[Ag8(C2)(CF3CO2)8(H2O)2] · 2H2O (1), [Ag14(C2)2(C2F5CO2)10(H2O)4(bpe)] · H2O (2), [Ag7(C2)(CF3CO2)2(cba)3] (3), [Ag7(C2)(C2F5CO2)5(cbaH)(H2O)2] (4) and (imH)3[Ag8(C2)(CF3CO2)9] · H2O (5) (bpe = trans-1,2-bis(4-pyridyl)ethylene, cbaH = 4-cyanobenzoic acid, im = imidazole) contain polyhedral silver(I) cages each encapsulating a C 2 2 - dianion. Complex 1 provides the first example of a layer-type inclusion complex constructed with C2@Agn polyhedra, whereas 2 and 3 both exhibit three-dimensional network structures, and 4 has a two-dimensional architecture. In 5, the imidazolium ions connect zig-zag anionic silver(I) columns to form a three-dimensional network via hydrogen bonding.

Six new silver(I) double salts, namely [Ag13(C2)2(CF3CO2)9(bipy)4(H2O)3] (1), [Ag18(C2)2(C2F5CO2)18(bipyH)4] · 3H2O (2), [Ag6(C2)(CF3CO2)4(bpp)] (3), [Ag6(C2)(C2F5CO2)5(bppH)]n (4), [Ag6(C2)(CF3CO2)5(bppH)]n (5) and [Ag23(C2)4(CF3CO2)15(bpp)6] · H2O (6) (bipy = 4,4′-bipyridine, bpp = bis(4-pyridyl)propane), have been hydrothermally synthesized and structurally characterized. In complex 1, the building units [Ag24(C2)4(CF3CO2)16(H2O)6] are connected by bipy ligands to form a two-dimensional network, which are further linked into a three-dimensional architecture via argentophilic interactions. Complex 2 is composed of two independent [Ag(bipyH)2]3+cations and a [Ag16(C2)2(C2F5CO2)18]6− cluster, whose core is a (C2)2@Ag16 double cage constructed from edge-sharing of two monocapped square antiprisms. Complex 3 has a two-dimensional architecture generated from bpp-bridged silver(I) columns. The virtually iso-structural complexes 4 and 5 each has a branched-tree architecture. The backbone is composed of fused silver(I) double cages, with C 2 2 - species embedded in its stem and an exterior coat comprising anionic perfluorocarboxyate and protonated bpp ligands. Complex 6 exhibits a two-dimensional architecture in which the basic building unit is an unusual silver(I) column composed of four consecutively fused C2@Agn cages.

We report the identification of the Disco Interacting Protein 1 (DIP1) gene isolated in a yeast interaction trap screen using the zinc finger protein disconnected (disco) as a bait. DIP1 encodes a protein containing two double-stranded RNA binding domains (dsRBD). Consistent with the presence of dsRBD, DIP1 binds dsRNA or structured RNAs in Northwestern assays. DIP1 is found in nuclear subdomains resembling speckles known to accumulate transcription and splicing factors. In early embryos, nuclear localization of DIP1 protein coincides with the onset of zygotic gene expression. Later in development DIP1 expression is decreased in dividing cells in different tissues. Overexpression of DIP1 in the eye-antennal imaginal disc, early in embryonic and larval development, causes the formation of supernumerary structures in the head capsule. A role for DIP1 in epigenetic mechanisms that lead to the establishment and/or maintenance of cell fate specification is discussed.

The complexes [Co(Him)2(μ4-bta)1/2]n 1 and {[Cu(phen)(μ4-bta)1/2]·H2O}n 2 were hydrothermally synthesized at 160°C and their structures were determined by single-crystal X-ray diffraction. Complex 1 was triclinic, space group P–1, a=7.9294(11) A, b=9.621(3) A, c=9.6461(16) A, α=116.772(19)°, β=96.791(13)°, γ=102.787(19)°, Z=2, V=620.3(2) A3, R1=0.0252 and wR2=0.0640 [I>2σ(I)]; complex 2 was monoclinic, space group P21/c, a=7.386(3) A, b=12.723(4) A, c=15.831(3) A, β=102.66(2)°, Z=4, V=1451.5(7) A3, R1=0.0389 and wR2=0.1033 [I>2σ(I)]. In both of the structures the metal ions were linked by the μ4-bridging benzene-1,2,4,5-tetracarboxylate ligands, resulting in one-dimensional double-metal chains. The synthesized products were characterized by IR spectroscopy, UV–VIS spectra, inductively coupled plasma (ICP), elemental, thermogravimetric (TGA) and magnetic analyses.

Surface properties of three cationic bolaamphiphile eicosanediyl 1,20-bis(pyridinium bromide) [Py � (CH2)20Py � ]2Br � , phenyl 1,4-bis(oxyhexyl trimethyl ammonium bromide) (C6PhC6), phenyl 1,4-bis(oxydecyl trimethyl ammonium bromide) (C10PhC10), and their mixed systems with oppositely charged conventional surfactant sodium dodecyl sulfite (SDS) were studied. The results showed that bolaamphiphiles with rigid group also adopted reverse U-shape conformation at the air/water interface as those with flexible skeleton. Micellization in these bolaamphiphile systems is easier than those of the comparable conventional surfactants. Micellization thermodynamic parameters were calculated according to the phase separation model and entropy was found to be the main driving force in the process of micellization. Diagrams for the C6PhC6/SDS and C20Py2/SDS mixed systems were constructed based on the regular solution theory. It was found that the structural difference between the two bolaamphileles affects the interaction between the two components in each mixed systems greatly. # 2002 Elsevier Science B.V. All rights reserved.

The time effect in a series of flexible and rigid bolaform amphiphiles and their mixed systems with oppositely charged conventional surfactants was investigated. An increase of surface tension with time was found in these systems at surfactant concentrations below the cmc. This result can be attributed to large numbers of surfactant molecules being gradually adsorbed on the wall of the vessel, which causes great changes of concentration and composition in mixed surfactant solutions. Contact angle data and UV research supported our proposal. It was also found that this reverse time effect in single bolaform cationic surfactant systems is decided by the structure of the hydrocarbon chains and only happens in flexible cationic bolaform surfactant solutions.

The employment of different Lewis bases pyridine and 3,5-DMpy under solvothermal conditions gave rise to two isostructural three-dimensional metal-organic frameworks: Co2(py)2(L)(DMA)2 (1) and Co2(L)(DMA)4 (2) (H4L = 5-(3,5-dicarboxybenzoylamino)-isophthalic acid, py = pyridine, DMA = N,N-dimethylacetamide, 3,5-DMpy = 3,5-dimethylpyridine). Single-crystal X-ray analysis has shown that 1 furnishes two different types of one-dimensional channels occupied by bridging DMA and terminal pyridine molecules. Changing pyridine to 3,5-DMpy in the assembly procedure affords 2, in which the channels are filled with bridging and terminal DMA molecules exclusively.