Interaction of the methylmercury cation with glycine and alanine: a vibrational and X-ray diffraction study

1986 ◽  
Vol 64 (9) ◽  
pp. 1876-1884 ◽  
Author(s):  
Marie-Claude Corbeil ◽  
André L. Beauchamp ◽  
Serge Alex ◽  
Rodrigue Savoie
Keyword(s):  
Aqueous Solutions ◽  
Diffraction Study ◽  
Raman Spectra ◽  
Infrared Spectra ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Carboxylate Oxygen

The complexes (CH3Hg)Gly, (CH3Hg)(L-Ala), and (CH3Hg)(DL-Ala) were prepared by reacting CH3HgOH with glycine (HGly) and alanine (HAla). Crystals of (CH3Hg)(DL-Ala) are monoclinic, space group P21/c, a = 9.460(2), b = 8.794(2), c = 8.723(2) Å, β = 97.49(2)°, Z = 4. The structure was refined on 935 MoKα reflections to R = 0.042. The complex results from displacement of an alanine NH3+ proton by the CH3Hg+ ion, which is linearly bonded to the —NH2 group. An intramolecular Hg … O contact of 2.63 Å is also formed with a carboxylate oxygen. The Raman and infrared spectra of solid (CH3Hg)Gly and (CH3Hg)(L-Ala) are compared with those of the ligands. Raman spectra of aqueous solutions at different pH indicate that the NH2-bonded structure is retained in solution, although no complexation via the carboxylate occurs.

Reactions of Transition-Metal Sigma-Acetylides. V. Synthesis and X-Ray Structure of Co2(µ-η2-PhC2Fe(Co)2(η-C5h5))(Co)6

1986 ◽  
Vol 39 (1) ◽  
pp. 159 ◽  
Author(s):  
MI Bruce ◽  
DN Duffy ◽  
MG Humphrey
Keyword(s):  
Molecular Structure ◽  
Transition Metal ◽  
Single Crystal ◽  
Diffraction Study ◽  
Title Complex ◽  
Monoclinic Space Group ◽  
Independent Data ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray

The reaction between Co2(CO)8 and Fe(C2Ph)(CO)2(η-C5H5) gave the title complex in 44% yield. The molecular structure was determined from a single-crystal X-ray diffraction study, and consists of the transition metal acetylide acting as a conventional μ- alkyne ligand to a Co2(CO)6 unit. Crystals are monoclinic, space group P21/n, with a 11.610(8), b 14.657(4), c 12.526(6)Ǻ, β 90.30(5)°, and Z 4; 1683 independent data were refined to R 0.080, Rw 0.087.

Preparation, infrared spectra, and crystal structure of two modifications of the (thymidinato-N3)methylmercury(II) complex

1985 ◽  
Vol 63 (12) ◽  
pp. 3456-3463 ◽  
Author(s):  
France Guay ◽  
André L. Beauchamp
Keyword(s):  
Infrared Spectra ◽  
Water Molecules ◽  
Monoclinic Space Group ◽  
Hydroxyl Groups ◽  
Carbonyl Groups ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
X Ray ◽  
Preparation Conditions

Reaction of CH3HgOH with thymidine (HT) yielded the neutral CH3HgT complex crystallizing as a hydrated or an anhydrous material, depending on preparation conditions. Both forms were examined by X-ray diffraction. The anhydrous variety is monoclinic, space group P21, a = 4.798(6), b = 14.270(8), c = 10.390(4) Å, β = 102.74(9)°, and Z = 2 molecules per cell. The structure was refined on 1552 nonzero MoKα reflections to a conventional R factor of 0.034. The hydrated form belongs to the orthorhombic space group P212121, a = 10.484(3), b = 14.633(3), c = 18.538(5), Z = 8. The structure was refined on 1816 nonzero MoKα reflections to R = 0.036. In both forms, the CH3Hg+ ion is linearly bonded to the deprotonated N(3) site of thymidine. The water molecules and hydroxyl groups in the ribose unit participate in a hydrogen bonding network, in which the carbonyl groups are involved as acceptors. The infrared spectra of the two forms differ significantly only by the absorptions due to the water molecules. By comparing with the spectrum of thymidine, diagnostic regions for complexation with deprotonated thymidine have been proposed

Kristallstrukturen, Schwingungsspektren und Normalkoordinatenanalyse von cis-(n-Bu4N)2[ReBr4(NCS)(SCN)], trans-(n-Bu4N)2[ReBr4(NCS)(SCN)] und trans-(n-Bu4N)2[ReBr4(NCSe)(SeCN)]

1999 ◽  
Vol 54 (8) ◽  
pp. 1009-1014 ◽  
Author(s):  
L. Homolya ◽  
W. Preetz
Keyword(s):  
Low Temperature ◽  
Single Crystal ◽  
Diffraction Analysis ◽  
Raman Spectra ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Normal Coordinate ◽  
Space Group ◽  
X Ray ◽  
Ir And Raman

The crystal structures of cis-(n-Bu4N)2[ReBr4(NCS)(SCN)] (1) (monoclinic, space group P21/n, a = 11.203(3), b = 11.738(5), c = 35.218(7) Å, β = 93.434(4)°, Z = 4), trans-(n-Bu4N)2[ReBr4(NCS)(SCN)] (2) (monoclinic, space group P21/n, a = 11.644(7), b = 13.695(3), c = 29.028(8) Å, β = 95.96(4)° Z = 4) and trans-(n-Bu4N)2[ReBr4(NCSe)(SeCN)] (3) (monoclinic, space group P21/n, a = 11.894(2), b = 13.737(2), c = 28.869(7) Å, β = 96.98(10)° Z = 4) have been determined by single crystal X-ray diffraction analysis. Based on these molecular parameters the low temperature (10 K) IR and Raman spectra of the (n-Bu4N) salts have been assigned by normal coordinate analysis. The valence force constants are fd(ReN) = 1.70 (1), 1.75 (2) and 1.75 (3), fd(ReS) = 1.32 (1) and 1.37 (2) and fd(ReSe) = 1.20 mdyn/Å (3).

Synthesis and reactivity of novel Schiff bases containing boronate esters

2002 ◽  
Vol 80 (1) ◽  
pp. 31-40 ◽  
Author(s):  
David W Norman ◽  
Janet P Edwards ◽  
Christopher M Vogels ◽  
Andreas Decken ◽  
Stephen A Westcott
Keyword(s):  
Molecular Structure ◽  
Diffraction Study ◽  
Schiff Bases ◽  
Oxidative Cyclization ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Boronate Esters ◽  
Space Group ◽  
X Ray ◽  
Manganese Triacetate

Condensation of 2-aminophenol with boronate ester derivatives of benzaldehyde afforded the corresponding boron-containing Schiff bases, 2-HOC6H4N=C(H)C6H4R (1a: R = 2-Bpin; 1b: R = 3-Bpin; 1c: R = 4-Bpin; pin = 1,2-O2C2Me4). Crystals of 1b were triclinic, space group P[Formula: see text], a = 11.9420(6), b = 13.0871(7), and c = 13.2720(7) Å, α = 70.983(1), β = 67.793(1), and γ = 78.380(1)°, Z = 2. Reaction of 2-aminophenol with 2-HC(O)C6H4B(OH)2 in EtOH, however, gave a macrocyclic dimer 2 with a OBOBO structural unit. The molecular structure of this dimer has been confirmed by an X-ray diffraction study. Crystals of 2 were monoclinic, space group P21/c, a = 10.0447(8), b = 21.0894(15), and c = 12.6214(9) Å, β = 105.301(2)°, Z = 4. Further reaction of these Schiff bases with manganese triacetate in toluene afforded 2-arylbenzoxazoles 3a–c via an oxidative cyclization pathway. The molecular structure of the 4-Bpin derivative (3c) was characterized by an X-ray diffraction study. Crystals of 3c were monoclinic, space group P21/n, a = 6.5392(3), b = 16.3330(8), and c = 16.1942(8) Å, β = 97.9620(10)°, Z = 4.Key words: boron heterocycles, Schiff bases, arylbenzoxazoles.

Late metal salicylaldimine complexes derived from 5-aminosalicylic acid — Molecular structure of a zwitterionic mono Schiff base zinc complex

2005 ◽  
Vol 83 (8) ◽  
pp. 1063-1070 ◽  
Author(s):  
Tara A Bourque ◽  
Megan E Nelles ◽  
Teri J Gullon ◽  
Christian N Garon ◽  
Melissa K Ringer ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Schiff Base ◽  
Diffraction Study ◽  
Monoclinic Space Group ◽  
Aminosalicylic Acid ◽  
X Ray Diffraction ◽  
Compound A ◽  
Space Group ◽  
X Ray ◽  
New Compounds

Condensation of salicylaldehyde (2-HOC6H4C(O)H) with 5-aminosalicylic acid (5-H2NC6H3-2-(OH)-CO2H) afforded the Schiff base 2-HOC6H4C(H)=NC6H3-2-(OH)-5-CO2H (a). Similar reactivity with 5-bromosalicylaldehyde was also observed to give 5-Br-2-HOC6H3C(H)=NC6H3-2-(OH)-5-CO2H (b). Reaction of these salicylaldehydes with Pd(II), Cu(II), and Zn(II) salts gave the corresponding bis(N-arylsalicylaldiminato)metal complexes (M = Pd (1), Cu (2), Zn (3)). The molecular structure of the Schiff base compound a has been confirmed by an X-ray diffraction study. Crystals of a were monoclinic, space group P2(1)/c, a = 7.0164(7) Å, b = 11.0088(11) Å, c = 14.8980(15) Å, β = 102.917(2)°, Z = 4. The molecular structure of a novel zwitterionic conformer of 3a was also characterized by an X-ray diffraction study. Crystals of 4 were monoclinic, space group P2(1)/c, a = 9.5284(5) Å, b = 19.5335(11) Å, c = 8.6508(5) Å, β = 90.596(1)°, Z = 4. All new compounds have been tested for their antifungal activity against Aspergillus niger and Aspergillus flavus. Key words: 5-aminosalicylic acid (5-ASA), antifungal, copper, palladium, salicylaldimines, Schiff base, zinc.

scholarly journals Polymorphie von Cs3Tl2Br9

1987 ◽  
Vol 42 (7) ◽  
pp. 818-824 ◽  
Author(s):  
Klaus Zimmermann ◽  
Gerhard Thiele
Keyword(s):  
Phase Transition ◽  
Thermal Analysis ◽  
Low Temperature ◽  
Aqueous Solutions ◽  
Closed System ◽  
Type Structure ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray

Abstract Cs3Tl2Br9, which has been synthesized either by heating a 3:2 mixture of CsBr/TlBr with bromine in a closed system or by reaction of these components in aqueous solutions, shows dimorphism. The phase transition (170 °C) was characterized by thermal analysis and X-ray diffraction. The low temperature modification α-Cs3TlBr9 crystallizes in the monoclinic space group P21/m (a = 964.98(9), b = 779.49(7), c = 1382.16(13) pm, β = 92.68(1)°, Z = 2). The structure is built up from TlBr6 octahedra linked by sharing vertices to chains and isolated TlBr4 tetrahedra. The high tem perature modification β-Cs3Tl2Br9 represents the undistorted trigonal Cs3Bi2Br9-type structure (a = 796.80(8), c - 982.98(15) pm).

New mixed-valent alkali chain sulfido ferrates A1+x[FeS2] (A = K, Rb, Cs; x = 0.333–0.787)

2020 ◽  
Vol 235 (8-9) ◽  
pp. 275-290
Author(s):  
Michael Schwarz ◽  
Pirmin Stüble ◽  
Katharina Köhler ◽  
Caroline Röhr
Keyword(s):  
Alkali Metal ◽  
General Structure ◽  
Variable Number ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Modulated Structure ◽  
Space Group ◽  
X Ray ◽  
Local Coordination ◽  
Natural Pyrite

AbstractFour new mixed-valent chain alkali metal (A) sulfido ferrates of the general structure family ${A}_{1+x}\left[{\text{Fe}}_{x}^{\text{II}}{\text{Fe}}_{1-x}^{\text{III}}{\text{S}}_{2}\right]$ were synthesized in the form of tiny green-metallic needles from nearly stoichiometric melts reacting elemental potassium with natural pyrite (A = K) or previously prepared Rb2S/Cs2S2 with elemental iron and sulfur (A = Rb/Cs). The crystal structures of the compounds were determined by means of single crystal X-ray diffraction: In the (3+1)D modulated structure of K7.15[FeS2]4 (space group Ccce(00σ3)0s0, a = 1363.87(5), b = 2487.23(13), c = 583.47(3) pm, q = 0,0,0.444, R1 = 0.055/0.148, x = 0.787), a position modulation of the two crystallographically different undulated ${}_{\infty }{}^{1}\left[{\text{FeS}}_{4/2}\right]$ tetrahedra chains and the surrounding K cations is associated with an occupation modulation of one of the three potassium sites. In the case of the new monoclinic rubidium ferrate Rb4[FeS2]3 (x = $\frac{1}{3}$; space group P21/c, a = 1640.49(12), b = 1191.94(9), c = 743.33(6) pm, β = 94.759(4)°, Z = 4, R1 = 0.1184) the undulation of the tetrahedra chain is commensurate, the repetition unit consists of six tetrahedra. In the second new Rb ferrate, Rb7[FeS2]5 (x = 0.4; monoclinic, space group C2/c, K7[FeS2]5-type; a = 2833.9(2), b = 1197.36(9), c = 744.63(6) pm, β = 103.233(4)°, Z = 4, R1 = 0.1474) and its isotypic mixed Rb/Cs-analog Rb3.6Cs3.4[FeS2]5 (a = 2843.57(5), b = 1226.47(2), c = 759.890(10) pm, β = 103.7170(9)°, R1 = 0.0376) the chain buckling leads to a further increased repetition unit of 10 tetrahedra. For all mixed-valent ferrates, the Fe–S bond lengths continuously increase with the amount (x) of Fe(II). The buckling of the chains is controlled through the local coordination of the S atoms by the variable number of A cations of different sizes.

Strukturuntersuchungen an Diaryldichalkogeniden: Die Molekülstrukturen von [2,4,6-(CF3)3C6H2S]2,[2,4,6-Me3C6H2Te]2 und [2-Me2N-4,6-(CF3)2C6H2Te]2 / Structural Investigations of Diaryl Dichalcogenides: The Molecular Structures of [2,4,6-(CF3)3C6H2S]2, [2,4,6-Me3C6H2Te]2 and [2-Me2N-4,6-(CF3)2C6H2Te]2

1992 ◽  
Vol 47 (3) ◽  
pp. 305-309 ◽  
Author(s):  
Anja Edelmann ◽  
Sally Brooker ◽  
Norbert Bertel ◽  
Mathias Noltemeyer ◽  
Herbert W. Roesky ◽  
...  
Keyword(s):  
Molecular Structures ◽  
Monoclinic Space Group ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Structural Investigations ◽  
Space Group ◽  
X Ray

Abstract The Molecular Structures of [2,4,6-(CF3)3C6H2S]2 (1) [2,4,6-Me3C6H2Te]2 and [2-Me2N-4,6-(CF3)2C6H2Te]2 (3) have been determined by X-ray diffraction. Crystal data: 1: orthorhombic, space group P212121, Z = 4, a = 822.3(2), b = 1029.2(2), c = 2526.6(5) pm (2343 observed independent reflexions, R = 0.042); 2: orthorhombic, space group Iba 2, Z = 8, a = 1546.5(2), b = 1578.4(2), c = 1483.9(1) pm (2051 observed independent reflexions, R = 0.030); 3: monoclinic, space group P 21/c, Z = 4, a = 1118.7(1), b = 1536.5(2), c = 1492.6(2) pm, β = 98.97(1)° (3033 observed independent reflexions, R = 0.025).

The Crystal and Molecular Structures of Two Modifications of cis-Dichloro-mer-tris-(dimethylphenylphosphine)hydridoiridium(III)

1988 ◽  
Vol 41 (3) ◽  
pp. 283 ◽  
Author(s):  
GB Robertson ◽  
PA Tucker
Keyword(s):  
Heavy Atom ◽  
Molecular Structures ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
X Ray ◽  
Bond Lengths ◽  
Metal Ligand ◽  
Ligand Bond

The structures of two crystalline modifications of mer -(Pme2Ph)3H-cis-Cl2IrIII, (1), have been determined from single-crystal X-ray diffraction data. Modification (A) is monoclinic, space group P21/c with a 12.635(1), b 30.605(3), c 14.992(2)Ǻ, β 110.01(2)° and Z = 8. Modification (B) is orthorhombic, space group Pbca with a 27.646(3), b 11.366(1), c 17.252(2)Ǻ and Z = 8. The structures were solved by conventional heavy atom techniques and refined by full-matrix least- squares analyses to conventional R values of 0.037 [(A), 8845 independent reflections] and 0.028 [(B), 5291 independent reflections]. Important bond lengths [Ǻ] are Ir -P(trans to Cl ) 2.249(1) av. (A) and 2.234(1) (B), Ir -P(trans to PMe2Ph) 2.339(2) av. (A) and 2.344(1), 2.352(1) (B), Ir-Cl (trans to H) 2.492(2), 2.518(2) (A) and 2.503(1) (B) and Ir-Cl (trans to PMe2Ph)2.452(2) av. (A) and 2.449(1)(B). Differences in chemically equivalent metal- ligand bond lengths emphasize the importance of non-bonded contacts in determining those lengths.

Silver(I)-Saccharinato Complexes with 2-(Aminomethyl)pyridine and 2-(2-Aminoethyl)pyridine Ligands: [Ag(sac)(ampy)] and [Ag2(sac)2(μ-aepy)2]

2005 ◽  
Vol 60 (9) ◽  
pp. 978-983 ◽  
Author(s):  
Sevim Hamamci ◽  
Veysel T. Yilmaz ◽  
William T. A. Harrison
Keyword(s):  
Thermal Analysis ◽  
Hydrogen Bonds ◽  
Monoclinic Space Group ◽  
Stacking Interactions ◽  
Coordination Geometry ◽  
X Ray Diffraction ◽  
Triclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
Pyridine Ligands

Two new saccharinato-silver(I) (sac) complexes, [Ag(sac)(ampy)] (1), and [Ag2(sac)2(μ-aepy)2] (2), [ampy = 2-(aminomethyl)pyridine, aepy = 2-(2-aminoethyl)pyridine], have been prepared and characterized by elemental analysis, IR spectroscopy, thermal analysis and single crystal X-ray diffraction. Complexes 1 and 2 crystallize in the monoclinic space group P21/c and triclinic space group P1̄, respectively. The silver(I) ions in both complexes 1 and 2 exhibit a distorted T-shaped AgN3 coordination geometry. 1 consists of individual molecules connected into chains by N-H···O hydrogen bonds. There are two crystallographically distinct dimers in the unit cell of 2 and in each dimer, the aepy ligands act as a bridge between two silver(I) centers, resulting in short argentophilic contacts [Ag1···Ag1 = 3.0199(4) Å and Ag2···Ag2 = 2.9894(4) Å ]. Symmetry equivalent dimers of 2 are connected by N-H···O hydrogen bonds into chains, which are further linked by aromatic π(py)···π(py) stacking interactions into sheets.

Sign in / Sign up

Export Citation Format

Share Document