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1.
Sophie Laurent Luce Vander Elst Antoine Vroman Robert N. Muller 《Helvetica chimica acta》2007,90(3):562-573
To confirm the observation that [Gd(ttda)] derivatives have a significantly shorter residence time τM of the coordinated H2O molecule than [Gd(dtpa)], four new C‐functionalized [Gd(ttda)] complexes, [Gd(4‐Me‐ttda)] ( 1 ), [Gd(4‐Ph‐ttda)] ( 2 ), [Gd(9‐Me‐ttda)] ( 3 ), and [Gd(9‐Ph‐ttda)] ( 4 ), were prepared and characterized (H5ttda=3,6,10‐tris(carboxymethyl)‐3,6,10‐triazadodecanedioic acid; H5dtpa=3,6,9‐tris(carboxymethyl)‐3,6,9‐triazaundecanedioic acid). The temperature dependence of the proton relaxivity for these complexes at 0.47 T and of the 17O transverse relaxation rate of H217O at 7.05 T confirm that the proton relaxivity is not limited by the H2O‐exchange rate. The residence time of the H2O molecules in the first coordination sphere of the gadolinium complexes at 310 K, as calculated from 17O‐NMR data, is 13, 43, 2.9, and 56 ns for 1, 2, 3 , and 4 , respectively. At 310 K, the longitudinal relaxivity of 2 is higher than for the parent compound [Gd(ttda)] and the other complexes of the series. The stability of the new compounds was studied by transmetallation with Zn2+ ions. All the new complexes are more stable than the parent compound [Gd(ttda)]. 相似文献
2.
Sophie Laurent Luce VanderElst Sylvain Houz Nathalie Gurit RobertN. Muller 《Helvetica chimica acta》2000,83(2):394-406
Four derivatives of diethylenetriaminepentaacetic acid (=3,6,9‐tris(carboxymethyl)‐3,6,9‐triazaundecanedioic acid (H5dtpa)), potential contrast agents for magnetic resonance imaging (MRI), carrying benzyl groups at various positions of the parent structure were synthesized and characterized by a thorough multinuclear NMR study, i.e., the (S)‐ and (R)‐stereoisomers 1a and 1b of 4‐benzyl‐3,6,9‐tris(carboxymethyl)‐3,6,9‐triazaundecanedioic acid (H5[(S)‐(4‐Bz)dtpa] and H5[(R)‐(4‐Bz)dtpa], the diamide derivative N,N″‐bis[(benzylcarbamoyl)methyl]diethylenetriamine‐N,N′,N″‐triacetic acid (=3,9‐bis[2‐(benzylamino)‐2‐oxoethyl]‐6‐(carboxymethyl)‐3,6,9‐triazaundecanedioic acid; H3[dtpa(BzA)2]; 2 ), and the diester derivative N,N″‐bis{[(benzyloxy)carbonyl]methyl}diethylenetriamine‐N,N′,N″‐triacetic acid (=3,9‐bis[2‐(benzyloxy)‐2‐oxoethyl]‐6‐(carboxymethyl)‐3,6,9‐triazaundecanedioic acid; H3[dtpa(BzE)2]; 3 ). From the 17O‐NMR chemical shift of H2O induced by their dysprosium complexes with ligands 1 – 3 , it was concluded that only one H2O molecule is contained in the first coordination sphere of these lanthanide complexes. The rotational correlation times (τR) of the complexes were estimated from the 2H‐NMR longitudinal relaxation rate of the deuterated diamagnetic lanthanum complexes. The exchange time of the coordinated H2O molecule (τM) was studied through the temperature dependence of the 17O‐NMR transverse relaxation rate. As compared to [Gd(dtpa)]2−, the H2O‐exchange rate is faster for [Gd{(S)‐(4‐Bz)dtpa}]2− and [Gd{(R)‐(4‐Bz)dtpa}]2−‐, slower for [Gd{dtpa(BzA)2}], and almost identical for [Gd{dtpa(BzE)2}]. The analysis of the 1H‐relaxivity of the gadolinium complexes recorded from 0.02 to 300 MHz established that i) the relaxivity of [Gd{dtpa(BzE)2}] is similar to that of [Gd(dtpa)]2−, ii) the slightly slower molecular rotation of [Gd{dtpa(BzA)2}] induces a mild enhancement of its relaxivity, and iii) the marked increase of relaxivity of [Gd{(S)‐(4‐Bz)dtpa}]2− and [Gd{(R)‐(4‐Bz)dtpa}]2− mainly results from an apparently shorter distance between the gadolinium ion and the H2O protons of the coordinated H2O molecule. 相似文献
3.
Herbert Schumann Esther C. E. Rosenthal Jrg Demtschuk Stefan Mühle 《无机化学与普通化学杂志》2000,626(10):2161-2166
Organometallic Compounds of the Lanthanides. 139 Mixed Sandwich Complexes of the 4 f Elements: Enantiomerically Pure Cyclooctatetraenyl Cyclopentadienyl Complexes of Samarium and Lutetium with Donor‐Functionalized Cyclopentadienyl Ligands The reactions of [K{(S)‐C5H4CH2CH(Me)OMe}], [K{(S)‐C5H4CH2CH(Me)NMe2}] and [K{(S)‐C5H4CH(Ph)CH2NMe2}] with the cyclooctatetraenyl lanthanide chlorides [(η8‐C8H8)Ln(μ‐Cl)(THF)]2 (Ln = Sm, Lu) yield the mixed cyclooctatetraenyl cyclopentadienyl lanthanide complexes [(η8‐C8H8)Sm{(S)‐η5 : η1‐C5H4CH2CH(Me)OMe}] ( 1 a ), [(η8‐C8H8)Ln{(S)‐η5 : η1‐C5H4CH2CH(Me)NMe2}] (Ln = Sm ( 2 a ), Lu ( 2 b )) and [(η8‐C8H8)Ln{(S)‐η5 : η1‐C5H4CH(Ph)CH2NMe2}] (Ln = Sm ( 3 a ), Lu ( 3 b )). For comparison, the achiral compounds [(η8‐C8H8)Ln{η5 : η1‐C5H4CH2CH2NMe2}] (Ln = Sm ( 4 a ), Lu ( 4 b )) are synthesized in an analogous manner. 1H‐, 13C‐NMR‐, and mass spectra of all new compounds as well as the X‐ray crystal structures of 3 b and 4 b are discussed. 相似文献
4.
Hiroshi Katagiri Masao Morimoto Kenichi Sakai 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(7):o357-o360
The structures of diastereomeric pairs consisting of (S)‐ and (R)‐2‐methylpiperazine with (2S,3S)‐tartaric acid are both 1:1 salts, namely (S)‐2‐methylpiperazinium (2S,3S)‐tartrate dihydrate, C5H14N22+·C4H4O62−·2H2O, (I), and (R)‐2‐methylpiperazinium (2S,3S)‐tartrate dihydrate, C5H14N22+·C4H4O62−·2H2O, (II), which reveal the formation of well defined ammonium carboxylate salts linked via strong intermolecular hydrogen bonds. Unlike the situation in the more soluble salt (II), the alternating columns of tartrate and ammonium ions of the less soluble salt (I) are packed neatly in a grid around the a axis, which incorporates water molecules at regular intervals. The increased efficiency of packing for (I) is evident in its lower `packing coefficient', and the hydrogen‐bond contribution is stronger in the more soluble salt (II). 相似文献
5.
The asymmetric hydroformylation of 2‐ and 3‐vinylfurans ( 2a and 2b , resp.) was investigated by using [Rh{(R,S)‐binaphos}] complexes as catalysts ((R,S)‐binaphos = (11bS)‐4‐{[1R)‐2′‐phosphino[1,1′‐binaphthalen]‐2‐yl]oxy}dinaphtho[2,1‐d:1′,2′‐f][1,3,2]dioxaphosphepin; 1 ). Hydroformylation of 2 gave isoaldehydes 3 in high regio‐ and enantioselectivities (Scheme 2 and Table). Reduction of the aldehydes 3 with NaBH4 successfully afforded the corresponding alcohols 5 without loss of enantiomeric purity (Scheme 3). 相似文献
6.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(7):856-862
Aminoalkanol and aroxyalkyl derivatives are known as potential anticonvulsants. Two new salts, namely bis{(R,S)‐N‐[2‐(2,6‐dimethylphenoxy)ethyl]‐1‐hydroxypropan‐2‐aminium} succinate ( 1s ), C13H22NO2+·0.5C4H4O42−, and bis{(S)‐(+)‐N‐[2‐(2,6‐dimethylphenoxy)ethyl]‐1‐hydroxypropan‐2‐aminium} succinate ( 2s ), C13H22NO2+·0.5C4H4O42−, have been prepared and characterized by single‐crystal X‐ray diffraction. The N atoms are protonated by proton transfer from succinic acid. Salt 1s crystallizes in the space group P21/n with one cation and half an anion in the asymmetric unit across an inversion centre, while ( 2s ) crystallizes in the space group P21 with four cations and two anions in the asymmetric unit. The hydroxy group of the cation of 1s is observed in two R/S disorder positions. The crystals of these two salts display similar supramolecular architectures (i.e. two‐dimensional networks), built mainly by intermolecular N+—H…Oδ− and O—H…Oδ− hydrogen bonds, where `δ−' represents a partial charge. The succinate anions are engaged in hydrogen bonds, not only with protonated N atoms, but also with hydroxy groups. 相似文献
7.
Xiu‐Hong Yang Ming‐Xing Yang Li‐Juan Chen Jing Guo Shen Lin 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(5):369-373
The title compound, [Cd3(C8H10O4)3(C12H9N3)2(H2O)2]n or [Cd3(chdc)3(4‐PyBIm)2(H2O)2]n, was synthesized hydrothermally from the reaction of Cd(CH3COO)2·2H2O with 2‐(pyridin‐4‐yl)‐1H‐benzimidazole (4‐PyBIm) and cyclohexane‐1,4‐dicarboxylic acid (1,4‐chdcH2). The asymmetric unit consists of one and a half CdII cations, one 4‐PyBIm ligand, one and a half 1,4‐chdc2− ligands and one coordinated water molecule. The central CdII cation, located on an inversion centre, is coordinated by six carboxylate O atoms from six 1,4‐chdc2− ligands to complete an elongated octahedral coordination geometry. The two terminal rotationally symmetric CdII cations each exhibits a distorted pentagonal–bipyramidal geometry, coordinated by one N atom from 4‐PyBIm, five O atoms from three 1,4‐chdc2− ligands and one O atom from an aqua ligand. The 1,4‐chdc2− ligands possess two conformations, i.e.e,e‐trans‐chdc2− and e,a‐cis‐chdc2−. The cis‐1,4‐chdc2− ligands bridge the CdII cations to form a trinuclear {Cd3}‐based chain along the b axis, while the trans‐1,4‐chdc2− ligands further link adjacent one‐dimensional chains to construct an interesting two‐dimensional network. 相似文献
8.
《Acta Crystallographica. Section C, Structural Chemistry》2017,73(5):382-392
Due to their versatile coordination modes and metal‐binding conformations, triazolyl ligands can provide a wide range of possibilities for the construction of supramolecular structures. Seven mononuclear transition metal complexes with different structural forms, namely aquabis[3‐(4‐methylphenyl)‐5‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazolato‐κ2N 1,N 5]zinc(II), [Zn(C14H11N4)2(H2O)], (I), bis[5‐(4‐methylphenyl)‐3‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazole‐κ2N 3,N 4]bis(nitrato‐κO )zinc(II), [Zn(NO3)2(C14H12N4)2], (II), bis(methanol‐κO )bis[3‐(4‐methylphenyl)‐5‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazolato‐κ2N 1,N 5]zinc(II), [Zn(C14H11N4)2(CH4O)2], (III), diiodidobis[5‐(4‐methylphenyl)‐3‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazole‐κ2N 3,N 4]cadmium(II), [CdI2(C14H12N4)2], (IV), bis[5‐(4‐methylphenyl)‐3‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazole‐κ2N 3,N 4]bis(nitrato‐κO )cadmium(II), [Cd(NO3)2(C14H12N4)2], (V), aquabis[3‐(4‐methylphenyl)‐5‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazolato‐κ2N 1,N 5]cobalt(II), [Co(C14H11N4)2(H2O)], (VI), and diaquabis[3‐(4‐methylphenyl)‐5‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazolato‐κ2N 1,N 5]nickel(II), [Ni(C14H11N4)2(H2O)2], (VII), have been prepared by the reaction of transition metal salts (ZnII, CdII, CoII and NiII) with 3‐(4‐methylphenyl)‐5‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazole (pymphtzH) under either ambient or hydrothermal conditions. These compounds have been characterized by elemental analysis, IR spectroscopy and single‐crystal X‐ray diffraction. All the complexes form three‐dimensional supramolecular structures through hydrogen bonds or through π–π stacking interactions between the centroids of the pyridyl or arene rings. The pymphtzH and pymphtz− entities act as bidentate coordinating ligands in each structure. Moreover, all the pyridyl N atoms are coordinated to metal atoms (Zn, Cd, Co or Ni). The N atom in the 4‐position of the triazole group is coordinated to the Zn and Cd atoms in the crystal structures of (II), (IV) and (V), while the N atom in the 1‐position of the triazolate group is coordinated to the Zn, Co and Ni atoms in (I), (III), (VI) and (VII). 相似文献
9.
Treatment of the biphenyl derivative [S=C{(NCH2But)2C6H3‐3,4}]2 or [Cl2Si{(NCH2But)2C6H3‐3,4}]2 with C8K afforded the new bis(carbene) 1 or the first bis(silylene) 2 , respectively. The X‐ray structure of 2 is presented. 相似文献
10.
Approaching the Kinetic Inertness of Macrocyclic Gadolinium(III)‐Based MRI Contrast Agents with Highly Rigid Open‐Chain Derivatives
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Dr. Gyula Tircsó Dr. Martín Regueiro‐Figueroa Viktória Nagy Zoltán Garda Tamás Garai Dr. Ferenc Krisztián Kálmán Dr. David Esteban‐Gómez Dr. Éva Tóth Dr. Carlos Platas‐Iglesias 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(3):896-901
A highly rigid open‐chain octadentate ligand (H4cddadpa) containing a diaminocylohexane unit to replace the ethylenediamine bridge of 6,6′‐[(ethane‐1,2 diylbis{(carboxymethyl)azanediyl})bis(methylene)]dipicolinic acid (H4octapa) was synthesized. This structural modification improves the thermodynamic stability of the Gd3+ complex slightly (log KGdL=20.68 vs. 20.23 for [Gd(octapa)]?) while other MRI‐relevant parameters remain unaffected (one coordinated water molecule; relaxivity r1=5.73 mm ?1 s?1 at 20 MHz and 295 K). Kinetic inertness is improved by the rigidifying effect of the diaminocylohexane unit in the ligand skeleton (half‐life of dissociation for physiological conditions is 6 orders of magnitude higher for [Gd(cddadpa)]? (t1/2=1.49×105 h) than for [Gd(octapa)]?. The kinetic inertness of this novel chelate is superior by 2–3 orders of magnitude compared to non‐macrocyclic MRI contrast agents approved for clinical use. 相似文献
11.
The analysis of 17O NMR transverse relaxation rates and EPR transverse electronic relaxation rates for aqueous solutions of the four DTPA‐like (DTPA = diethylenetriamine‐N,N,N′,N″,N″‐pentaacetic acid) complexes, [Gd(DTPA‐PY)(H2O)]? (DTPA‐PY = N′‐(2‐pyridylmethyl)), [Gd(DTPA‐HP)(H2O)2]? (DTPA‐HP = N′‐(2‐hydroxypropyl)), [Gd(DTPA‐H1P)(H2O)2]? (DTPA‐H1P = N′‐(2‐hydroxy‐1‐phenylethyl)) and [Gd(DTPA‐H2P)(H2O)2] (DTPA‐H2P = N′‐(2‐hydroxy‐2‐phenylethyl)), at various temperatures allows us to understand the water exchange dynamics of these four complexes. The water‐exchange lifetime (τM) parameters for [Gd(DTPA‐PY)(H2O)]?, [Gd(DTPA‐HP)(H2O)2]?, [Gd(DTPA‐H1P)(H2O)2]? and [Gd(DTPA‐H2P)(H2O)2] are of 585, 98, 163, and 69 ns, respectively. Compared with [Gd(DTPA)(H2O)]2? (τM = 303 ns), the τM value of [Gd(DTPA‐PY)(H2O)]? is slightly higher, but the other three complexes values are significantly lower than those of [Gd(DTPA)(H2O)]2?. This difference is explained by the fact that the gadolinium(III) complexes of DTPA‐HP, DTPA‐H1P, and DTPA‐H2P have two inner‐sphere waters. The 2H longitudinal relaxation rates of the labeled diamagnetic lanthanum complex allow the calculation of its rotational correlation time (τR). The τR values calculated for DTPA‐PY, DTPA‐HP, DTPA‐H1P, and DTPA‐H2P are of 127, 110, 142 and 147 ps, respectively. These four values are higher than the value of [La(DTPA)]2? (τR = 103 ps), because the rotational correlation time is related to the magnitude of its molecular weight. 相似文献
12.
Hiroshi Katagiri Masao Morimoto Kenichi Sakai 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(1):o20-o24
The crystal structures of a pair of diastereomeric 1:2 salts of (R)‐ and (S)‐2‐methylpiperazine with (2S,3S)‐tartaric acid, namely (R)‐2‐methylpiperazinediium bis[hydrogen (2S,3S)‐tartrate] monohydrate, (I), and (S)‐2‐methylpiperazinediium bis[hydrogen (2S,3S)‐tartrate] monohydrate, (II), both C5H14N22+·2C4H5O6−·H2O, each reveal the formation of well‐defined head‐to‐tail‐connected hydrogen tartrate chains; these chains are linked into a two‐dimensional sheet via intermolecular hydrogen bonds involving hydroxy groups and water molecules, resulting in a layer structure. The (R)‐2‐methylpiperazinediium ions lie between the hydrogen tartrate layers in the most stable equatorial conformation in (I), whereas in (II), these ions are in an unstable axial position inside the more interconnected layers and form a larger number of intermolecular hydrogen bonds than are observed in (I). 相似文献
13.
Vitalie Stavila Ion Bulimestru Aurelian Gulea Adam C. Colson Kenton H. Whitmire 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(3):m65-m68
The title complexes, hexaaquacobalt(II) bis(μ‐pyridine‐2,6‐dicarboxylato)bis[(pyridine‐2,6‐dicarboxylato)bismuthate(III)] dihydrate, [Co(H2O)6][Bi2(C7H4NO4)4]·2H2O, (I), and hexaaquanickel(II) bis(μ‐pyridine‐2,6‐dicarboxylato)bis[(pyridine‐2,6‐dicarboxylato)bismuthate(III)] dihydrate, [Ni(H2O)6][Bi2(C7H4NO4)4]·2H2O, (II), are isomorphous and crystallize in the triclinic space group P. The transition metal ions are located on the inversion centre and adopt slightly distorted MO6 (M = Co or Ni) octahedral geometries. Two [Bi(pydc)2]− units (pydc is pyridine‐2,6‐dicarboxylate) are linked via bridging carboxylate groups into centrosymmetric [Bi2(pydc)4]2− dianions. The crystal packing reveals that the [M(H2O)6]2+ cations, [Bi2(pydc)4]2− anions and solvent water molecules form multiple hydrogen bonds to generate a supramolecular three‐dimensional network. The formation of secondary Bi...O bonds between adjacent [Bi2(pydc)4]2− dimers provides an additional supramolecular synthon that directs and facilitates the crystal packing of both (I) and (II). 相似文献
14.
Jaromír Marek Pavel Kopel Zdenk Trvní
ek 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(12):m558-m560
In the crystal structure of the title compound, [N,N′‐bis(3‐aminopropyl)ethylenediamine‐κ4N,N′,N′′,N′′′][1,3,5‐triazine‐2,4,6(1H,3H,5H)‐trithionato(2−)‐κ2N,S]zinc(II) ethanol solvate, [Zn(C8H22N4)2(C3HN3S3)]·C2H6O, the ZnII atom is octahedrally coordinated by four N atoms [Zn—N = 2.104 (2)–2.203 (2) Å] of a tetradentate N‐donor N,N′‐bis(3‐aminopropyl)ethylenediamine (bapen) ligand and by two S and N atoms [Zn—S = 2.5700 (7) Å and Zn—N = 2.313 (2) Å] of a trithiocyanurate(2−) (ttcH2−) dianion bonded as a bidentate ligand in a cis configuration. The crystal structure of the compound is stabilized by a network of hydrogen bonds. 相似文献
15.
Reaction of a mixture of AgOAc, Lawesson's reagent [2,4‐bis(4‐methoxyphenyl)‐1,3‐dithiadiphosphetane‐2,4‐disulfide] and 1,3‐bis(diphenylphosphanyl)propane (dppp) under ultrasonic treatment gave the title compound, {[Ag(C9H12O2PS2)(C27H26P2)]·CHCl3}n, a novel one‐dimensional chain based on the in situ‐generated bipodal ligand [ArP(OEt)S2]− (Ar = 4‐methoxyphenyl). The compound consists of bidentate bridging 1,3‐bis(diphenylphosphanyl)propane (dppp) and in situ‐generated bidentate chelating [ArP(OEt)S2]− ligands. The dppp ligand links the [Ag{ArP(OEt)S2}] subunit to form an achiral one‐dimensional infinite chain. These achiral chains are packed into chiral crystals by virtue of van der Waals interactions. No π–π interactions are observed in the crystal structure. 相似文献
16.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(8):967-973
Crystals of poly[[aqua[μ3‐4‐carboxy‐1‐(4‐carboxylatobenzyl)‐2‐propyl‐1H‐imidazole‐5‐carboxylato‐κ5O1O1′:N3,O4:O5][μ4‐1‐(4‐carboxylatobenzyl)‐2‐propyl‐1H‐imidazole‐4‐carboxylato‐κ7N3,O4:O4,O4′:O1,O1′:O1]cadmium(II)] monohydrate], {[Cd2(C15H14N2O4)(C16H14N2O6)(H2O)]·H2O}n or {[Cd2(Hcpimda)(cpima)(H2O)]·H2O}n, (I), were obtained from 1‐(4‐carboxybenzyl)‐2‐propyl‐1H‐imidazole‐4,5‐dicarboxylic acid (H3cpimda) and cadmium(II) chloride under hydrothermal conditions. The structure indicates that in‐situ decarboxylation of H3cpimda occurred during the synthesis process. The asymmetric unit consists of two Cd2+ centres, one 4‐carboxy‐1‐(4‐carboxylatobenzyl)‐2‐propyl‐1H‐imidazole‐5‐carboxylate (Hcpimda2−) anion, one 1‐(4‐carboxylatobenzyl)‐2‐propyl‐1H‐imidazole‐4‐carboxylate (cpima2−) anion, one coordinated water molecule and one lattice water molecule. One Cd2+ centre, i.e. Cd1, is hexacoordinated and displays a slightly distorted octahedral CdN2O4 geometry. The other Cd centre, i.e. Cd2, is coordinated by seven O atoms originating from one Hcpimda2− ligand and three cpima2− ligands. This Cd2+ centre can be described as having a distorted capped octahedral coordination geometry. Two carboxylate groups of the benzoate moieties of two cpima2− ligands bridge between Cd2 centres to generate [Cd2O2] units, which are further linked by two cpima2− ligands to produce one‐dimensional (1D) infinite chains based around large 26‐membered rings. Meanwhile, adjacent Cd1 centres are linked by Hcpimda2− ligands to generate 1D zigzag chains. The two types of chains are linked through a μ2‐η2 bidentate bridging mode from an O atom of an imidazole carboxylate unit of cpima2− to give a two‐dimensional (2D) coordination polymer. The simplified 2D net structure can be described as a 3,6‐coordinated net which has a (43)2(46.66.83) topology. Furthermore, the FT–IR spectroscopic properties, photoluminescence properties, powder X‐ray diffraction (PXRD) pattern and thermogravimetric behaviour of the polymer have been investigated. 相似文献
17.
Fabrice O. M. Gaslain Ann M. Chippindale 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(11):m537-m540
The title compound, {(C2H10N2)2[Mn(PO4)2]}n, contains anionic square‐twisted chains of formula [Mn(PO4)2]4− constructed from corner‐sharing four‐membered rings of alternating MnO4 and PO4 units. The Mn and P atoms have distorted tetrahedral coordination and the Mn atom lies on a twofold axis. The linear manganese–phosphate chains are held together by hydrogen‐bonding interactions involving the framework O atoms and the H atoms of the ethane‐1,2‐diammonium cations, which lie in the interchain spaces. 相似文献
18.
Anna Doga Katarzyna Baranowska Agnieszka Pladzyk Katarzyna Majcher 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(7):m259-m263
The complexes [2‐(1H‐imidazol‐4‐yl‐κN3)ethylamine‐κN]bis(tri‐tert‐butoxysilanethiolato‐κS)cobalt(II), [Co(C12H27O3SSi)2(C5H9N3)], and [2‐(1H‐imidazol‐4‐yl‐κN3)ethylamine‐κN]bis(tri‐tert‐butoxysilanethiolato‐κS)zinc(II), [Zn(C12H27O3SSi)2(C5H9N3)], are isomorphous. The central ZnII/CoII ions are surrounded by two S atoms from the tri‐tert‐butoxysilanethiolate ligand and by two N atoms from the chelating histamine ligand in a distorted tetrahedral geometry, with two intramolecular N—H...O hydrogen‐bonding interactions between the histamine NH2 groups and tert‐butoxy O atoms. Molecules of the complexes are joined into dimers via two intermolecular bifurcated N—H...(S,O) hydrogen bonds. The ZnII atom in [(1H‐imidazol‐4‐yl‐κN3)methanol]bis(tri‐tert‐butoxysilanethiolato‐κ2O,S)zinc(II), [Zn(C12H27O3SSi)2(C4H6N2O)], is five‐coordinated by two O and two S atoms from the O,S‐chelating silanethiolate ligand and by one N atom from (1H‐imidazol‐4‐yl)methanol; the hydroxy group forms an intramolecular hydrogen bond with sulfur. Molecules of this complex pack as zigzag chains linked by N—H...O hydrogen bonds. These structures provide reference details for cysteine‐ and histidine‐ligated metal centers in proteins. 相似文献
19.
《Acta Crystallographica. Section C, Structural Chemistry》2017,73(4):325-330
Structures having the unusual protonated 4‐arsonoanilinium species, namely in the hydrochloride salt, C6H9AsNO3+·Cl−, (I), and the complex salts formed from the reaction of (4‐aminophenyl)arsonic acid (p‐arsanilic acid) with copper(II) sulfate, i.e. hexaaquacopper(II) bis(4‐arsonoanilinium) disulfate dihydrate, (C6H9AsNO3)2[Cu(H2O)6](SO4)2·2H2O, (II), with copper(II) chloride, i.e. poly[bis(4‐arsonoanilinium) [tetra‐μ‐chlorido‐cuprate(II)]], {(C6H9AsNO3)2[CuCl4]}n , (III), and with cadmium chloride, i.e. poly[bis(4‐arsonoanilinium) [tetra‐μ‐chlorido‐cadmate(II)]], {(C6H9AsNO3)2[CdCl4]}n , (IV), have been determined. In (II), the two 4‐arsonoanilinium cations are accompanied by [Cu(H2O)6]2+ cations with sulfate anions. In the isotypic complex salts (III) and (IV), they act as counter‐cations to the {[CuCl4]2−}n or {[CdCl4]2−}n anionic polymer sheets, respectively. In (II), the [Cu(H2O)6]2+ ion sits on a crystallographic centre of symmetry and displays a slightly distorted octahedral coordination geometry. The asymmetric unit for (II) contains, in addition to half the [Cu(H2O)6]2+ ion, one 4‐arsonoanilinium cation, a sulfate dianion and a solvent water molecule. Extensive O—H…O and N—H…O hydrogen bonds link all the species, giving an overall three‐dimensional structure. In (III), four of the chloride ligands are related by inversion [Cu—Cl = 2.2826 (8) and 2.2990 (9) Å], with the other two sites of the tetragonally distorted octahedral CuCl6 unit occupied by symmetry‐generated Cl‐atom donors [Cu—Cl = 2.9833 (9) Å], forming a two‐dimensional coordination polymer network substructure lying parallel to (001). In the crystal, the polymer layers are linked across [001] by a number of bridging hydrogen bonds involving N—H…Cl interactions from head‐to‐head‐linked As—O—H…O 4‐arsonoanilinium cations. A three‐dimensional network structure is formed. CdII compound (IV) is isotypic with CuII complex (III), but with the central CdCl6 complex repeat unit having a more regular M —Cl bond‐length range [2.5232 (12)–2.6931 (10) Å] compared to that in (III). This series of compounds represents the first reported crystal structures having the protonated 4‐arsonoanilinium species. 相似文献
20.
Hatem M. Titi Anirban Karmakar Israel Goldberg 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(9):m238-m244
We report the synthesis of the 2,2′‐[2,5‐bis(carboxymethoxy)‐1,4‐phenylene]diacetic acid (TALH4) ligand and the structures of its adducts with ammonium, namely diammonium 2,2′‐[2,5‐bis(carboxymethyl)‐1,4‐phenylenedioxy]diacetate, 2NH4+·C14H12O102−, (I), lanthanum, namely poly[[aquabis[μ4‐2,2′‐(2‐carboxylatomethyl‐5‐carboxymethyl‐1,4‐phenylenedioxy)diacetato]dilanthanum(III)] monohydrate], {[La2(C14H11O10)2(H2O)]·H2O}n, (II), and zinc cations, namely poly[[{μ4‐2,2′‐[2,5‐bis(carboxymethyl)‐1,4‐phenylenedioxy]diacetato}zinc(II)] trihydrate], {[Zn(C14H12O10)]·3H2O}n, (III), and poly[[diaqua(μ2‐4,4′‐bipyridyl){μ4‐2,2′‐[2,5‐bis(carboxymethyl)‐1,4‐phenylenedioxy]diacetato}dizinc(II)] dihydrate], {[Zn2(C14H10O10)(C10H8N2)(H2O)2]·2H2O}n, (IV), the formation of all four being associated with deprotonation of TALH4. Adduct (I) is a diammonium salt of TALH22−, with the ions located on centres of crystallographic inversion. Its crystal structure reveals a three‐dimensional hydrogen‐bonded assembly of the component species. Reaction of TALH4 with lanthanum trinitrate hexahydrate yielded a two‐dimensional double‐layer coordination polymer, (II), in which the LaIII cations are nine‐coordinate. With zinc dinitrate hexahydrate, TALH4 forms 1:1 two‐dimensional coordination polymers, in which every ZnII cation is linked to four neighbouring TALH22− anions and each unit of the organic ligand is coordinated to four different tetrahedral ZnII cation connectors. The crystal structure of this compound accommodates molecules of disordered water at the interface between adjacent polymeric layers to give (III), and it has been determined with low precision. Another polymer assembly, (IV), was obtained when zinc dinitrate hexahydrate was reacted with TALH4 in the presence of an additional 4,4′‐bipyridyl ligand. In the crystal structure of (IV), the bipyridyl and TAL4− entities are located on two different inversion centres. The ternary coordination polymers form layered arrays with corrugated surfaces, with the ZnII cation connectors revealing a tetrahedral coordination environment. The two‐dimensional polymers in (II)–(IV) are interconnected with each other by hydrogen bonds involving the metal‐coordinated and noncoordinated molecules of water. TALH4 is doubly deprotonated, TALH22−, in (I) and (III), triply deprotonated, viz. TALH3−, in (II), and quadruply deprotonated, viz. TAL4−, in (IV). This report provides the first structural characterization of TALH4 (in deprotonated form) and its various supramolecular adducts. It also confirms the potential utility of this tetraacid ligand in the formulation of coordination polymers with metal cations. 相似文献