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Placentals are the most abundant mammals that have diversified into every niche for vertebrates and dominated the world's terrestrial biotas in the Cenozoic. A critical event in mammalian history is the divergence of eutherians, the clade inclusive of all living placentals, from the metatherian-marsupial clade (1-8). Here we report the discovery of a new eutherian of 160 Myr from the Jurassic of China, which extends the first appearance of the eutherian-placental clade by about 35 Myr from the previous record, reducing and resolving a discrepancy between the previous fossil record and the molecular estimate for the placental-marsupial divergence (9-13). This mammal has scansorial forelimb features, and provides the ancestral condition for dental and other anatomical features of eutherians., Class Mammalia Clade Boreosphenida (14) Infraclass Eutheria Order and family incertae sedis Juramaia sinensis gen. et sp. nov. Etymology. Jura, Jurassic; mala, mother, in reference to placental affinities; sinensis, of [...]

Author(s): Zhe-Xi Luo (corresponding author) [1, 2]; Qing-Jin Meng (corresponding author) [3]; David M. Grossnickle [2]; Di Liu [3]; April I. Neander [1]; Yu-Guang Zhang [3]; Qiang Ji [4] Stem [...]

Stem mammaliaforms are Mesozoic forerunners to mammals, and they offer critical evidence for the anatomical evolution and ecological diversification during the earliest mammalian history. Two new eleutherodonts from the Late Jurassic period have skin membranes and skeletal features that are adapted for gliding. Characteristics of their digits provide evidence of roosting behaviour, as in dermopterans and bats, and their feet have a calcaneal calcar to support the uropagatium as in bats. The new volant taxa are phylogenetically nested with arboreal eleutherodonts. Together, they show an evolutionary experimentation similar to the iterative evolutions of gliders within arboreal groups of marsupial and placental mammals. However, gliding eleutherodonts possess rigid interclavicleclavicle structures, convergent to the avian furculum, and they retain shoulder girdle plesiomorphies of mammaliaforms and monotremes. Forelimb mobility required by gliding occurs at the acromionclavicle and glenohumeral joints, is different from and convergent to the shoulder mobility at the pivotal claviclesternal joint in marsupial and placental gliders., Author(s): Qing-Jin Meng [1]; David M. Grossnickle [2]; Di Liu [1]; Yu-Guang Zhang [1]; April I. Neander [3]; Qiang Ji [4]; Zhe-Xi Luo (corresponding author) [2, 3] Mammaliaforms of the [...]

Research has been conducted on heteropolynuclear organometallic compounds. The authors describe the construction of these compounds via application of ferrocene-based ligands.

Research has been conducted on neutral mixed-valent Cu (super)I Cu (super)II (sub)2 triangular metallomacrocycle. The authors demonstrate that this compound has been asembled via the reaction of the tetradentate ligand with copper(II) salt.

A new organic fluorescent ionic compound [MOBIP]I (1) (MOBIP+ = 1-methyl-2-oxo-3 -(1H-benzimidazol-2(3H)-ylidene)-2,3-dihydropyridinium) was synthesized and used to prepare seven maleonitriledithiolate metal complexes [MOBIP] n [M(mnt)2] by substitution of the iodide ion with [M(mnt)2] n − (M = Cu2+ (2), Ni2+ (3a), Ni3+ (3b), Zn2+ (4), Cd2+ (5), Pd2+ (6), and Pt2+ (7)). An investigation of fluorescence properties shows that these complexes are a new series of solution luminescent complexes of maleonitriledithiolate derivatives with strong blue light fluorescence in daylight by irradiation with UV light with high quantum yields. They display similar symmetric emissions with λem at the deep blue region of ∼426 nm upon excitation at ∼364 nm in DMF, caused by L–L transition of MOBIP+. Existence of [M(mnt)2] n − anions in the solution prolongs the fluorescent lifetimes. For all these compounds in the solid state, the fluorescent emission is blue-shifted and more narrow than that in solution. Based on their crystal structure analysis, the weak stacking interactions in compounds cause the difference of their fluorescence spectrum. Investigations of variable-temperature magnetic susceptibility indicate that 2 has weak antiferromagnetic coupling, while 3b exhibits stronger antiferromagnetic coupling. [ABSTRACT FROM AUTHOR]

Two novel lanthanide coordination polymers, [Eu2(EBTC)(DMF)5(NO3)2]·DMF (1) and [Eu2(BBTC)1.5(CH3OH)2(H2O)2]·7DMF·HNO3(2) (EBTC4−= 1,1′-ethynebenzene-3,3′,5,5′-tetracarboxylate; BBTC4−= 1,1′-butadiynebenzene-3,3′,5,5′-tetracarboxylate), were successfully synthesized from conjugated ligands of EBTC4−and BBTC4−. Although the two tetracarboxylate ligands have similar structures, their different rigidity/flexibility results in quite different networks upon complexation. Complex 1has a two-dimensional (2-D) layered structure with two crystallographically independent Eu3+ions, one in a distorted monocapped square-antiprism and the other in a distorted square-antiprism coordination geometry. Complex 2exhibits a three-dimensional (3-D) porous framework, with one type of Eu3+in a distorted square-antiprism and the other in a trigondodecahedron environment. Both 1and 2emit the intensely red characteristic luminescence of Eu3+ion at room temperature, with a long lifetime of up to 1.3 and 0.7 ms, respectively, during which the ligand emission of EBTC4−/BBTC4−was quenched by the Eu3+ion, indicating the existence of efficient energy transfer between the conjugated ligand of EBTC4−/BBTC4−and the Eu3+ion. Thus, both EBTC4−and BBTC4−are ideal ligands with an “antenna” effect for the Eu3+ion. The two complexes show the single-ion magnetic behaviors of Eu3+with strong spin–orbit coupling interactions even if there are shorter distances (5.714 Å for 1versus4.275 and 5.360 Å for 2) between the neighboring Eu3+ions connected by oxygen atoms of the tetracarboxylates. [ABSTRACT FROM AUTHOR]

A low-dimensional compound [C6-Apy][Ni(mnt)2] (1, where mnt2−= maleonitriledithiolate, C6-Apy+= 4-amino-1-hexylpyridinium) has been designed and synthesized, which has layer arrangement of anions and cations and shows two steps of magnetic transitions. The low temperature magnetic transition has an uncommon hysteresis loop, while the crystal structure investigations disclosed no structural transition with the magnetic transition. The high temperature magnetic transition exhibits two remarkable features: (1) it synchronously occurs with a crystalline-to-mesophase transition in the first heating process and (2) the structural changes that accompany the solid-mesophase transition are irreversible. A diamagnetic and isostructural compound, [C6-Apy][Cu(mnt)2], is further characterized by structure, DSC and POM techniques, which revealed also the existence of an irreversible crystalline-to-mesophase transition in the same temperature interval of [C6-Apy][Ni(mnt)2]. Therefore, the high-temperature magnetic transition in 1is driven by release of the structural strains, but not magnetoelastic interactions. The mesophase exhibits the characteristic of smectic A phase, and the alkyl chain melting in the cation layers probably lead to the formation of mesophase. It is noticeable that the finding of a mesophase occurring in a hexyl hydrocarbon chain molecular system is in contrast to a suggested rule that at least a dodecyl chain is required. Our results will shed a light on the design and preparation of a new low-dimensional molecular system combining magnetic transition and liquid crystal properties. [ABSTRACT FROM AUTHOR]

[Ni(hmp)(MeOH)Br]4 ⋅ 2H2O has been prepared by the reaction of 2-hydroxymethylpyridine with NiBr2 ⋅ 3H2O and characterized by IR, elemental analysis, powder X-ray diffraction, thermogravimetric analyses, magnetic measurements, and single crystal X-ray diffraction. The crystal structure shows two independent [Ni(hmp)(MeOH)Br]4 molecules in the asymmetric unit and [Ni4O4]4+ cubane-type cores. Each octahedral Ni(II) is bridged by four μ3-CH2O- fragments from four hmp- ligands. Magnetic studies show that ferromagnetic coupling gives an S = 4 ground state with significant magnetoanisotropy, and the parameters are J1 = 8.56, J2 = 2.28, D = -0.65 cm-1, and g ≈ 2.13. [ABSTRACT FROM AUTHOR]

Two new salts, [2-NaMePy]2[Ni(i-mnt)2] (1) and [2-NaMe-4-MePy]2[Ni(i-mnt)2] (2) ([2-NaMePy]+ = 1-(2'-naphthylmethyl)pyridinium, [2-NaMe-4-MePy]+ = 1-(2'-naphthylmethyl)-4-methylpyridinium and i-mnt2- = iso-maleonitriledithiolate), have been prepared and characterized by elemental analyses, UV, IR, molar conductivity, and single crystal X-ray diffraction. The anions in 1 form a 1-D chain through short C ··· N interactions between the anions, while the cations in 2 stack a 1-D column via C-H ··· π and π ··· π stacking interactions between the cations. The effect of weak intramolecular interactions such as C-H ··· N, C-H ··· S, C-H ··· Ni hydrogen bonds, and π ··· π stacking interactions between the cations and the anions further generate a 3-D network structure. The change of the molecular topology of the countercation when the 4-substituted group in the pyridine ring is changed from H atom to CH3 group results in different crystal system, space group, and the stacking mode of the cations and anions of 1 and 2. [ABSTRACT FROM AUTHOR]

A new ion-pair complex, [BzTPP]2[Ni(i-mnt)2](1) (i-mnt2- = iso-maleonitriledithiolate, [BzTPP]+ = benzyltriphenylphosphinium) was synthesized and characterized by elemental analysis, IR, UV, EI-MS spectra and single crystal X-ray diffraction. The single-crystal structural analysis shows that 1 crystallizes in the triclinic space group P-1, with a = 9.466(1) Å, b = 10.196(1)Å, c = 29.252(3)Å, α = 99.28(1)ˆ, β = 93.96(1)ˆ, γ = 106.34(1)ˆ, V = 2654.3(4)Å3, Z = 2. The Ni(II) ions of the [Ni(i-mnt)2]2 - anion adopted a square-planar coordination geometry. Four weak C─H...N hydrogen bonds between the anions and the cations observed in the crystal give further rise to a 3D structure. [ABSTRACT FROM AUTHOR]

Three novel coordination polymers, [Mn(TPB)0.5(IPA)(H2O)2]n (1), [Zn1.5(TPB)0.5(TMA)(H2O)·(H2O)]n (2), and [Co(TPB)0.5(PMA)0.5(H2O)2·(H2O)]n (3) (TPB = 1,2,3,4-tetra-(4-pyridyl)-butane; H2IPA = isophthalic acid; H3TMA = trimesic acid; and H4PMA = pyromellitic acid), have been synthesized under hydrothermal conditions and structurally characterized. Complex 1 features a 2D infinite layer framework consisting of bi-manganese clusters, which is further stacked along the [1&cmb.macr;11] direction via strong interlayer π⋯π interactions to form a 3D supramolecular architecture. Complex 2 has a 3D complicated framework comprised of two kinds of infinite 1D chains. The 3D framework of complex 3 possesses three topologically nonequivalent 4-connected nodes synchronously and exhibits an unprecedented (64·102)(42·84)(4·65)2 topology. The magnetic susceptibility data of complex 1 show strong antiferromagnetic interactions in the dinuclear Mn(ii) units. Complex 2 exhibits strong fluorescent emissions in the solid state at room temperature and may be suitable as a candidate of blue-fluorescent material. [ABSTRACT FROM AUTHOR]

The synthesis, molecular structure and spectroscopic and magnetic properties of (NH4)2(15-crown-5)3[Ni(mnt)2]2 (mnt  =  maleonitriledithiolate dianion) are reported. The most notable structural feature of (NH4)2(15-crown-5)3[Ni(mnt)2]2 is that the ions form a stacked structure with well-separated columns along the c and a axes. Variable temperature magnetic susceptibility measurements indicate strong antiferromagnetic interactions in the complex. [ABSTRACT FROM AUTHOR]

A new ternary complex [Cu(glygly)(AMBZ)(H 2 O)]Cl·H 2 O ( 1 ) (glygly = glycylglycine anion, AMBZ = 2-aminomethylbenzimidazole) has been prepared and characterized by single-crystal X-ray diffractometry and ESR, electronic and IR spectroscopy. The copper(II) ion has a slightly distorted square-pyramidal coordination, being equatorially coordinated by the bidentate 2-aminomethylbenzimidazole and the bidentate glycylglycine anion and axially by a water molecule. The individual complex molecules are hydrogen bonded to their neighbors, forming a polymeric hydrogen-bonded lattice. Spectroscopic data are in accordance with the crystal structure. [ABSTRACT FROM AUTHOR]

A new polymer complex of copper(II)-glycylglycine {[Cu(glygly)(H 2 O)][Cu(glygly)(H 2 O) 2 ]} n ·5 n H 2 O ( 1 ) is reported. It crystallizes in the P 2 1 / c space group, with a = 14.669(2), b = 9.8480(10), c = 14.053(2) Å, β = 102.730(10)° and Z = 4. Compound 1 consists of [Cu(glygly)(H 2 O)] n 1D carboxylate-bridged polymeric chains, monomer Cu(glygly)(H 2 O) 2 molecules which form hydrogen-bonded chains and uncoordinated water molecules. In all cases, the geometry around copper(II) is a slightly distorted square pyramid with the water oxygen at the apex of the pyramid. The ESR, UV-Vis and IR spectroscopy of the compound were also studied. [ABSTRACT FROM AUTHOR]