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Four new compounds, formulated as [Zn(m-Pip)2(3-Phpy)]2 (1), [Zn(m-Pip)2(4-Phpy)]2 (2), [Cd(m-Pip)(Pip)(3-Phpy)2]2 (3) and [Cd(m-Pip)(Pip)(4-Phpy)2]2 (4) (HPip=1,3-benzodioxole-5-carboxylic acid; Phpy= phenylpyridine), have been successfully assembled based on rigid carboxylate/pyridine ligands. These four compounds have been fully characterized by analytical and spectroscopic methods. The aim of the present study is to investigate the structural effect and the influence of the size of metal on the class, geometry and type of coordination of the carboxylate ligands (syn-syn, syn-anti) in the final 3D-arrangements of the structures. Finally, luminescence properties of these new four coordination dimers have been investigated.

The reaction of (1S,2R)-[(η5-C5H 5)Fe{(η5-C5H4)-CH=N-CH(Me)- CH(OH)(C6H5)}] (1) with Na2[PdCl4] in the presence of Na(OAc)·3H2O produced three diastereomerically pure tetrametallic cyclopalladated complexes (6b I-6bIII). In two of them (6bI and 6b II), the imine 1 adopts the [C(sp2,ferrocene),N] - mode of binding, but they differ in the planar chirality of the 1,2-ferrocenyl unit (Sp in 6bI and Rp in 6bII), whereas ligand 1 in 6bIII acts as a [C(sp 2,phenyl),N]- group. Treatment of 6bI-6b III with PPh3 gave [Pd{κ2-C, N{(η5-C5H3)-CH=N-CH(Me)-CH(OH)(C 6H5)}Fe(η5-C5H 5)}Cl(PPh3)] (7bI, 7bII) and [Pd{κ2-C,N{(C6H4)-CH(OH)-CH(Me)-N=CH- (η5-C5H4)}Fe(η5-C 5H5)}Cl(PPh3)] (7bIII). The Pt II compounds [Pt{κ2-C,N{(η5-C 5H3)-CH=NCH(Me)CH(OH)(C6H5)} Fe(η5-C5H5)}Cl(PPh3)] [(S p,1S,2R) and (Rp,1S,2R) diastereomers, 7aI and 7aII, respectively)] have also been prepared. The results of electrochemical studies of 6bI-6bIII, 7b I-7bIII, 7aI, 7aII and related PtII complexes with 1 acting as an (N) or (N,O)- ligand are also reported. Comparison of the results provides conclusive evidence for the relative influence of the mode of binding of the ligand, the nature of the MII atom, the type of metallated atom C(sp2,phenyl or ferrocenyl), the ancillary ligands and their relative disposition on the electrochemical properties of this type of compound. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim., This work was supported by the Spanish Ministerio de Ciencia e Innovación (MICINN) [grant number CTQ2009-11501 (subprogram BQU)].

Many physical properties (e.g., hardness, texture, rheology, and spreadability) of lipid‐based products largely depend on the extent of crystallization and transformation of lipids, and their network formation. Therefore, many studies have focused on controlling the crystallization of lipids in order to determine the functionality of lipid crystals. Both internal and external factors greatly affect the processes of lipid crystallization. The most important internal factors are polymorphism, which depends on variation in fatty acid moieties, and the composition or blending of different lipid materials. Important external factors are thermal treatment, additives, application of shear, sonication, and pressure. This paper briefly reviews recent advances in research on these external factors. We discuss the results by considering the relationships between external factors and thermodynamics, as well as kinetic properties of the crystallization and transformation of polymorphic forms of lipid crystals.

A series of nickel complexes with nuclearity ranging from Ni(3) to Ni(6) have been obtained by treatment of a variety of nickel salts with the 2-pyridylcyanoxime ligand. The reported compounds have as a common structural feature the triangular arrangement of nickel cations bridged by a central μ(3)-oxo/alkoxo ligand. These compounds are simultaneously the first nickel derivatives of the 2-pyridylcyanoxime ligand and the first examples of isolated, μ(3)-O triangular pyridyloximate nickel complexes. Magnetic measurements reveal antiferromagnetic interactions promoted by the μ(3)-O and oximato superexchange pathways and comparison of the experimental structural and magnetic data with DFT calculations give an in-depth explanation of the factors that determine the magnetic interaction in this kind of system.

A study of the reactivity of [Pd({(η5-C5H3)–CH=N–(CH2)n–(C4H3S)}Fe{η5-C5H5})Cl], n = 2 (1e) or 1 (1f), with symmetric alkynes R1–C≡C–R1 (R1 = CO2Me, Et or Ph) has allowed us to achieve the di-μ-chloro-bridged complexes [Pd({(MeO2C–C=C–CO2Me)(η5-C5H3)–CH=N–(CH2)n–(C4H3S)}Fe{η5-C5H5})μ-Cl]2, n = 2 (3e) or 1 (3f), and the mononuclear derivatives [Pd({(MeO2C–C=C–CO2Me)(η5-C5H3)–CH=N–(CH2)n–(C4H3S)}Fe{η5-C5H5})Cl(PPh3)], n = 2 (4e) or 1 (4f), [Pd({(R1–C=C–R1)2(η5-C5H3)–CH=N–(CH2)n–(C4H3S)}Fe{η5-C5H5})Cl],R1 = CO2Me, n = 2 (5e) or 1 (5f), R1 = Et, n = 2 (6e) or 1 (6f), or R1 = Ph, n = 2 (7e), and [Pd({(Ph–C=C–Ph)2(η5-C5H3)–CH=N–(CH2)–(C4H3S)}Fe{η5-C5H5})Cl(PPh3)] (7f·1/2Ph–C≡C–Ph). With MeO2C–C≡C–CO2Me, mono- (3e, 3f, 4e and 4f) and bis-insertion complexes (5e and 5f) were obtained, whereas for R1–C≡C–R1 with R1 = Et or Ph, only bis-insertion products (6e, 6f, 7e and 7f) were isolated. These studies also proved that 1e and 1f, which have a labile Pd–S(thienyl) bond, are more prone to undergo the insertion of R1–C≡C–R1 (R1 = CO2Me, Et or Ph) than their analogues with [C(sp2, ferrocene), N, X]– [X = O, N(amine) or S(thioether)] pincer ligands.

Treatment of the monoimine (E)-N-benzylidene-2-(2,6-dichlorophenyl)ethanamine (1) with a stoichiometric amount of Pd(OAc)2 in acetic acid at 60 °C under nitrogen produced the corresponding acetato-bridged endo five-memberedortho-cyclopalladated dimer [Pd{C6H4CH=N(CH2)2(2,6-Cl2C6H3)}(μ-OAc)]2 (2), which was isolated in pure form in 80 % yield. Reaction of 2 with an excess of LiCl in acetone gave rise to the corresponding chlorido-bridged cyclopalladated dimer [Pd{C6H4CH=N(CH2)2(2,6-Cl2C6H3)}(μ-Cl)]2 (3) in 88 % yield. Compounds 2 and 3 reacted with an excess of [D5]pyridine or a stoichiometric amount of PPh3 to give the mononuclear compounds trans-N,L-[Pd{C6H4CH=N(CH2)2(2,6-Cl2C6H3)}(X)(L)] (4: X = OAc, L = [D5]py; 5: X = Cl, L = [D5]py; 6: X = OAc, L = PPh3; 7: X = Cl, L = PPh3). Compounds 4 and 5 were prepared in a CDCl3/[D5]py solution and studied by 1H and 13C{1H} NMR spectroscopy, but they were not isolated. Compound 3 was treated with different types of symmetric bidentate Lewis bases in a 1:1 molar ratio to give high yields of the dinuclear compounds trans-N,L-[(Pd{C6H4CH=N(CH2)2(2,6-Cl2C6H3)}Cl)2{μ-L2}] [8: L2 = Ph2PCH2CH2PPh2; 9: L2 = trans-Ph2PCH=CHPPh2; 10: L2 = 4,4′-bipyridine; 11: L2 = NH2CH2CH2OCH2CH2OCH2CH2NH2; 12: L2 = NH2CH2(CHOH)CH2NH2)] in which the symmetric bidentate Lewis base bridged two identical cyclopalladated units. Compounds 1–3 and 6–12 were fully characterized by elemental analysis, mass spectrometry, IR and 1H and 13C{1H} NMR spectroscopy. In addition, the crystal structures of 2, 8·2CH2Cl2, 10·4CHCl3 and 11·2CH2Cl2 were determined by single-crystal X-ray diffraction analysis. Also reported is the theoretical study of the differences in the absolute Gibbs free energies in acetone or CHCl3 solution between the cis- and trans-N,L stereoisomers of compounds [Pd(C-N)(X)(L)] in which Pd(C-N) is a model of an endo five-membered ortho-cyclopalladated imine, X is OAc, Cl, Br or I and L is py, NH3 or PH3.

A convenient and novel oxazol-5-one addition to nitrostyrenes is reported. The reaction is catalyzed by tertiary amines and yields the corresponding adducts with total regio- and diastereoselectivity. The addition exclusively takes place at the C-2 position of oxazol-5-ones, furnishing diastereopure N,O-aminals.

Three new manganese compounds have been obtained by reaction of the 2,6-diacetylpyridine dioxime (dapdoH2) ligand with several MnII salts. By using a variety of manganese(II) carboxylates, three MnII derivatives with general formula [Mn3(RCOO)6(dapdoH2)2], where RCOO– = formate (1), acetate (2), and benzoate (3), were obtained. Structural analysis reveals chains of trinuclear units for 1 and isolated trinuclear molecules for 2. Compound 1 provides an example of a new topology for the [Mn3(RCOO)6(L)2] general formula. Magnetic susceptibility studies reveal topological ferrimagnetism for 1 and conventional antiferromagnetic response for 2 and 3, with coupling constants of –3.1, –3.2, and –1.4 cm–1 inside the trimeric units of 1, 2, and 3, respectively.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

The experimental temperature/composition phase diagram of the binary system decanedioic acid (C10H18O4)/dodecanedioic acid (C12H22O4) was established by combining X-ray powder diffraction (XRD), differential-scanning calorimetry (DSC), infrared spectroscopy (IR), scanning electron microscopy (SEM), and thermo-optical microscopy (TOM). Both compounds crystallize in the same ordered form, C (P21/c), which is the phase that melts in both cases. The C form melts in C12H22O4 earlier than in C10H18O4 , in contrast to other unbranched-chain compounds (alkanes, alkanols, and alkanoic acids) in which the melting temperatures increase as the C-atom number rises. Contrary to what might be expected, total solid-state miscibility is not observed. The C10H18O4/C12H22O4 binary system shows a complex phase diagram. At low temperatures, a new monoclinic form, Ci (P21/c), stabilizes as a result of the disorder of composition in the mixed samples; two [C þ Ci] domains appear. Upon heating, four solid - solid and seven solid - liquid domains appear related by eutectic and peritectic invariants. All the crystallographic forms observed are isostructural.

Complementary techniques had to be applied to investigate the binary system tetradecanedioic acid (C14H26O4)–hexadecanedioic acid (C16H30O4), because all the forms observed have the same space group (P21/c; Z = 2). We studied the polymorphism of the two single compounds and of their mixtures by X-ray powder diffraction, differential-scanning calorimetry (DSC), infrared spectroscopy (IR), scanning electron microscopy (SEM), and thermo-optical microscopy (TOM). The two diacids were found to be isopolymorphic. At low temperature, they crystallize in the same ordered C-form, and, on heating, adopt the ordered Ch-form, 1° below their melting point. In contrast to similar compounds (unbranched alkanes, alkanols, and fatty acids), the solid–solid and solid–liquid phase-transition temperatures decrease with increasing chain length. At low temperature, a new monoclinic form, Ci, appears as a result of the disorder of composition in the mixed samples. There are two [C + Ci]-type solid–solid domains. On heating, the solid domains are related to solid–liquid domains by a peritectic invariant for compositions rich in C14H26O4, and by a eutectic invariant for compositions rich in C16H30O4. At higher temperature, there appears a second peritectic invariant for compositions rich in C14H26O4, together with a metatectic invariant for compositions rich in C16H30O4. All the solid forms observed in this binary system are isostructural. Nevertheless, the equilibrium between them is complex near the melting point, and their miscibility in the solid state is reduced.

The cross metathesis (CM) of methylenecyclopentane derivatives using Hoveyda—Grubbs second generation catalyst is studied.

PTU is used in several enantioselective Michael reactions of trans-β-nitrostyrene (I) with 1,3-dicarbonyl compounds.

A convenient and novel oxazol-5-one addition to nitrostyrenes is reported. The reaction is catalyzed by tertiary amines and yields the corresponding adducts with total regio- and diastereoselectivity. The addition exclusively takes place at the C-2 position of oxazol-5-ones, furnishing diastereopure N,O-aminals.