{"title":"Crystal Structure of cis-Bis(2,2′-bipyridyl)bis(trifluoromethanesulfonato)cobalt(II)","authors":"Mari Toyama, Yuichi Yamamoto","doi":"10.2116/XRAYSTRUCT.35.21","DOIUrl":"https://doi.org/10.2116/XRAYSTRUCT.35.21","url":null,"abstract":"Cobalt(II) complexes with polypyridyl ligands were used as photo-catalysts for hydrogen generation from water,1 sensitizers in dye-sensitized solar cells,2 or building blocks for magnetic supramoleculars,3 because of their redox and magnetic properties. When synthesizing a new functional cobalt(II) complex with polypyridyl ligands, such as cis-[Co(L)2(N-N)2] or cis-[Co(L-L)(N-N)2] (L = monodentate ligand, L-L = bidentate ligand, N-N = 2,2′-bipyridine (bpy) or 1,10-phenanthroline (phen) etc.), cis-[Co(solvent)2(N-N)2] or cis-[CoII(OTf )2(N-N)2] (OTf– = trifluoromethanesulfonato or CF3SO3) have been utilized as a precursor.3 This is a popular synthetic method for not only cobalt(II) complexes, but also many transition metal complexes. However, there are only four reports concerning the crystal structure of cis-[MII(OTf )2(bpy)2] (M = Mn, Ni, Cu, or Zn),3 because OTf– ligands might be too labile to be isolated from a reaction solution as single crystals. Smith and co-workers prepared cis-[MII(OTf )2(bpy)2] (M = Mn or Co) complexes from the reaction of cis-[MCl2(bpy)2] with Ag(OTf ) in acetonitrile.3 The cis-[MnII(OTf )2(bpy)2] complex was characterized by elemental analysis, IR spectra, and X-ray crystal structure, whereas the Co(II) complex was reported based on only IR spectroscopic data. Fortunately, we were able to determine the crystal structure of cis-[CoII(OTf )2(bpy)2] (Fig. 1). Here we report on it, and compare the lattice parameters of our Co2+ complex with those of other transition metal complexes, cis-[MII(OTf )2(bpy)2]. We obtained yellow crystals of cis-[CoII(OTf )2(bpy)2], which were suitable for X-ray crystallography, from the reaction mixture of [Co(CO)3(bpy)2](OTf )4 and di-2-pyridylamine (Hdpa) in EtOH–H2O containing a small amount of HOTf(aq). We expected that [Co(bpy)2(Hdpa)] would be obtained from the reaction, but the anticipated complex was not yielded. The 1H NMR spectrum of the product showed that [Co(bpy)3] and a CoIII-Hdpa complex, probably [Co(Hdpa)3] or trans[Co(OH2)2(Hdpa)2], existed in the NMR sample. We tried to crystalize the CoIII-Hdpa complex by the vapor diffusion of diethyl ether into an EtOH–MeOH (1:1) solution of the mixed product. However, this plan went wrong. From the solution, two kinds of yellow crystals, which had different shapes, for [Co(bpy)3](OTf )3 and cis-[CoII(OTf )2(bpy)2], and a yellowbrown oily product, which would be the CoIII-Hdpa complex, were obtained. The Co2+ complex, cis-[CoII(OTf )2(bpy)2], might be produced from a reduction reaction of the Co3+ complex, [Co(CO3)(bpy)2], by EtOH in the reaction solution. We thought that it would be important for coordination chemists, because it is the first report concerning the crystal structure of cis-[CoII(OTf )2(bpy)2]. In 2013, Kurahashi and Fujii reported on a very unique cobalt complex with a salen ligand (Fig. S1, Supporting Information) and an OTf– ligand, [Co(salen)(OTf )], which was characterized by X-ray crystallography, cyclic voltammetry,","PeriodicalId":23922,"journal":{"name":"X-ray Structure Analysis Online","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2019-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47501849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xi Zhang, H. Furutachi, Yuya Ohyama, S. Fujinami, Shigehisa Akine, Masatatsu Suzuki
{"title":"Crystal Structure of Bis(μ-hydroxo)diiron(III) Complex with Tripodal Ligands Having a Terminal Carboxylate Group","authors":"Xi Zhang, H. Furutachi, Yuya Ohyama, S. Fujinami, Shigehisa Akine, Masatatsu Suzuki","doi":"10.2116/XRAYSTRUCT.35.17","DOIUrl":"https://doi.org/10.2116/XRAYSTRUCT.35.17","url":null,"abstract":"Hydroxoor oxo-bridged non-heme diiron centers with terminal carboxylates are structural motifs found in metalloproteins, such as soluble methane monooxygenase (sMMO) and ribonucleotide reductase (RNR).1–4 Synthetic diiron model complexes with Fe2(OH)2, Fe2(O)(OH), and Fe2(O)2 cores are of particular importance for obtaining fundamental insights into the structural and spectroscopic properties of the active centers in the metalloproteins mentioned above.2–4 Previously, we reported that the crystal structure of a (μ-oxo)(μ-hydroxo)diiron(III) complex, [Fe2(6Me2-BPP)2(O)(OH)] (2),5 with a tetradentate tripodal ligand (6Me2-BPP) having a terminal carboxylate, which was derived from deprotonation of its conjugate acid, [Fe2(6Me2-BPP)2(OH)2]. In this paper, we report on the crystal structure of the bis(μ-hydroxo)diiron(III) complex [Fe2(6Me2BPP)2(OH)2](NO3)1.9553·Br0.0447·8H2O (1) (Fig. 1). A single crystal of [Fe2(6Me2-BPP)2(OH)2](NO3)1.9553·Br0.0447· 8H2O (1) suitable for X-ray crystallography was obtained by the recrystallization of [Fe2(6Me2-BPP)2(OH)2](NO3)2·4.5H2O from water. It was picked up on a hand-made cold copper plate mounted inside a liquid N2 Dewar vessel and mounted on a glass rod at –80°C. X-ray diffraction measurements were made on a Rigaku CCD Mercury diffractometer with graphite monochromated Mo Kα radiation at 123 K. The structure was solved by a direct method (SHELXS 97)6 and expanded using a Fourier technique. The structure was refined by a full-matrix least-squares method by using the SHELXL 20147 (YadokariXG).8 The asymmetric unit contains two very similar molecules that could be nearly related by each other with a translation symmetry in the [0 1 1] direction. This could be interpreted as a structure with a half unit-cell volume. However, the counter anions (NO3, Br –) and crystallizing water molecules are located at different positions that could not be related by a translational symmetry. Also, the diffractions with k + l = odd showed significant intensities (around 1/3 of those with k + l = even). Therefore, we concluded that the structure should have two independent molecules in the asymmetric unit. All nonhydrogen atoms were refined with anisotropic displacement parameters. The hydrogen atoms in the μ-hydroxo groups and water molecules were restrained to ensure reasonable distances (0.84 Å) by applying the default values for O–H DFIX restraints. Other hydrogen atoms were included using a riding model. The crystal data are summarized in Table 1. X-ray crystallography of 1 reveals that the asymmetric unit contains two halves of complex cations, [Fe2(6Me2-BPP)2(OH)2] (molecules A and B), 1.9553 nitrate ions, 0.0447 bromide ion, and eight water molecules. The partial content of the bromide ion appears to be due to the preparation route of the 6Me2BPPH ligand, which was obtained from the reaction of bis(6methyl-2-pyridylmethyl)amine with 3-bromopropionic acid in the presence of triethylamine.5 ORTEP drawing of the complex cati","PeriodicalId":23922,"journal":{"name":"X-ray Structure Analysis Online","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2019-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46200627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mio Sekino, H. Furutachi, Kyosuke Tasaki, T. Ishikawa, S. Fujinami, Shigehisa Akine, Y. Sakata, Masatatsu Suzuki, Takashi Nomura, T. Ogura, T. Kitagawa
{"title":"Crystal Structure of Bis(μ-hydroxo)diiron(II) Complex with a Dinucleating Ligand Having a Butyl Linker","authors":"Mio Sekino, H. Furutachi, Kyosuke Tasaki, T. Ishikawa, S. Fujinami, Shigehisa Akine, Y. Sakata, Masatatsu Suzuki, Takashi Nomura, T. Ogura, T. Kitagawa","doi":"10.2116/XRAYSTRUCT.35.5","DOIUrl":"https://doi.org/10.2116/XRAYSTRUCT.35.5","url":null,"abstract":"","PeriodicalId":23922,"journal":{"name":"X-ray Structure Analysis Online","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2019-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2116/XRAYSTRUCT.35.5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47381515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Crystal Structure of Tertiarybutyl Ammonium Bis[(naphthalene-2,3-diolato)borate] Dimethyl Sulfoxide Solvate","authors":"M. Tombul","doi":"10.2116/xraystruct.35.3","DOIUrl":"https://doi.org/10.2116/xraystruct.35.3","url":null,"abstract":"Ammonium The structure of tertiarybutyl ammonium bis[naphthalene-2,3-diolato)borate] dimethyl sulfoxide solvate was determined by X-Ray crystallography. The compound crystallized in a triclinic system, and was characterized to be in the space group P -1, with cell parameters a = 9.6282(9)Å, b = 11.0221(9)Å, c = 13.0273(12)Å, α = 91.050(4) 0 , β = 109.419(4) 0 , γ = 94.574(2) 0 , Z = 2, and V = 1298.2(2)Å 3 . The crystal packing is governed by intermolecular and intramolecular N–H···O hydrogen bonds. The B atom takes a distorted tetrahedral geometry with four O atoms of naphthalene-2,3-diolato ligands.","PeriodicalId":23922,"journal":{"name":"X-ray Structure Analysis Online","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2019-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2116/xraystruct.35.3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43469408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Crystal Structure of Gramicidin S Hydrochloride at 1.1 Å Resolution","authors":"A. Asano, M. Doi","doi":"10.2116/XRAYSTRUCT.35.1","DOIUrl":"https://doi.org/10.2116/XRAYSTRUCT.35.1","url":null,"abstract":"","PeriodicalId":23922,"journal":{"name":"X-ray Structure Analysis Online","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2019-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48719134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Molecular Planarity and Crystal Structures of N-Salicylideneaminopyrazine Derivatives","authors":"Haruki Sugiyama","doi":"10.2116/XRAYSTRUCT.34.57","DOIUrl":"https://doi.org/10.2116/XRAYSTRUCT.34.57","url":null,"abstract":"Schiff bases (also called azomethines) are considered to be important organic compounds containing acyclic and cyclic imine C=N bonds, which have various applications in photoluminescence materials,1 optical materials and devices,2 organic light-emitting diodes,3 oxidation hair dyes4 and color print materials.5 N-Salicylideneaniline (SA), which is one of the Schiff bases, and its structural analogues are known to show photochromism in the crystalline state upon UV light irradiation.6 Interestingly, SA crystals including non-planar molecules with dihedral angle between two aromatic rings greater than 30° are photochromic, and those including planar molecules with a dihedral angle of less than 20° are non-photochromic.7,8 N-Salicylidene aminopyrazine (SAPz) is one of the SA derivatives that include a pyrazine (Pz) (Fig. 1). SAPz derivative molecules would prefer a planar conformation by taking one of two possible Pz orientations, which avoids the intramolecular H to H steric repulsion between Pz C–H and imine C–H. On the other hand, SA derivatives have always suffered from such steric repulsions, so the conformation may not be necessarily planar. In order to demonstrate that SAPz crystals have planar molecules, but no photochromic property, we synthesized two SAPz derivatives of 2SAPZ (1) and 3,5-Br-2SAPZ (2), and analyzed their crystal structures and photochromic properties. The synthesis schemes of compounds 1 and 2 are as follows: A mixture of salicylaldehyde derivative (10 mmol) and 2-aminopyrazine (10 mmol) was heated at 393 K for 2 h without a plug. The resulting melt was cooled, and then red crude title compounds were precipitated. Single crystals were obtained by recrystallizations from chloroform and methanol, respectively. Single crystals X-ray diffraction data were collected at 293 K on a R-AXIS RAPID imaging plate area detector (RIGAKU) using graphite-monochromated Mo-Kα radiation from a rotating anode source. Scaling and absorption corrections were performed using ABSCOR.9 Crystal data and refinement details of 1 and 2 are given in Table 1. The initial structures were determined by using a dual space method with SHELXT-2014/4, and refined by full-matrix least-squares on Fo with SHELXL-2018/1.10,11 All hydrogen atoms were found in the difference Fourier map; however, they were placed by geometrical calculations and treated using a riding model with Uiso(H) = 1.2 × Ueq(C) or 1.5 × Ueq(O). ORTEP drawings are shown in Fig. 2. The hydrogen-bond lengths and angles in the crystal of 1 and 2 are summarized in Tables S1 and S2 (Supporting Information), respectively. Solid-state diffuse reflectance spectra were measured at 298 K with a JASCO V-560 spectrometer. Analytical samples were prepared as a mixture of the 2SAPz crystals (10 mg) and barium sulfate powder (100 mg). UV irradiation was performed with a high-power UV-LED irradiator (Keyence Corporation) at a wavelength of 365 nm. The measured spectra are shown in Fig. S1 (Supporting Informati","PeriodicalId":23922,"journal":{"name":"X-ray Structure Analysis Online","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2018-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2116/XRAYSTRUCT.34.57","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46803810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Handa, H. Kamada, D. Yoshioka, I. Hiromitsu, K. Kasuga, M. Mikuriya
{"title":"Crystal Structure of a Supramolecular Complex Built up from Molybdenum(II) Trifluoroacetate and Copper(II) Schiff-Base Components, [{CuLt-Bu}2{Mo2(O2CCF3)4}3(H2O)2]n, H2Lt-Bu = 2,3-bis((5-tert-butyl-2-hydroxybenzylidene)amino)-2,3-butenedinitrile","authors":"M. Handa, H. Kamada, D. Yoshioka, I. Hiromitsu, K. Kasuga, M. Mikuriya","doi":"10.2116/XRAYSTRUCT.34.59","DOIUrl":"https://doi.org/10.2116/XRAYSTRUCT.34.59","url":null,"abstract":"There has been much interest for the use of tetracarboxylato dimetal complexes with a lantern-like structure as building blocks in combination with bridging ligands to construct two or three-dimensional architectures, because they show remarkable properties, such as gas-occlusion and ferrior ferromagnetism.1–3 Here, we report on a new assembled complex, [{CuL}2 {Mo2(O2CCF3)4}3(H2O)2] (1), H2L = 2,3-bis((5-tert-butyl-2hydroxybenzylidene)amino)-2,3-butenedinitrile. The copper(II) complex with a Schiff-base ligand ([CuLt-Bu]) is paramagnetic, based on the d9 configuration, although the lantern-type dinuclear molybdenum(II) complex is diamagnetic based on the σ2π4δ2 configuration of the Mo–Mo quadruple bond core. The phenoxido oxygen of [CuLt-Bu] was shown to participate in the axial interaction with the molybdenum(II) dinuclear core to assemble the component complex units, giving the supramolecular chain structure (Fig. 1).","PeriodicalId":23922,"journal":{"name":"X-ray Structure Analysis Online","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2018-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42543171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}