X-ray evidence for metal–N-7 bonding in a hydrated manganese derivative of guanosine 5′-monophosphate

Single-crystal X-ray studies of a manganese(II) derivative of guanosine 5′-monophosphate, [Mn(5′-GMP)(H2O)5],3H2O, have shown that it is isostructural with its nickel analogue. The manganese atom therefore is bonded to five water molecules with the remaining octahedral co-ordination site being occupied by N-7 of the nucleotide base. No direct metal–phosphate bonding is involved, but there are structure-stabilizing intramolecular hydrogen bonds between two phosphate oxygen atoms and co-ordinated water molecules.

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Unusual crystal structure ofN-substituted maleamic acid – very strong effect of intramolecular hydrogen bonds

Acta Crystallographica Section B Structural Science Crystal Engineering and Materials ◽

10.1107/s2052520614018952 ◽

2014 ◽

Vol 70 (6) ◽

pp. 942-947 ◽

Cited By ~ 2

Author(s):

Raju Francis ◽

Pallepogu Raghavaiah ◽

Kuruvilla Pius

Keyword(s):

Crystal Structure ◽

Hydrogen Bonds ◽

Single Crystal ◽

Amide Group ◽

Intramolecular Hydrogen Bonds ◽

X Ray ◽

Planar Molecule ◽

C And N ◽

Maleamic Acid ◽

Intramolecular Hydrogen

N-Carbamylmaleamic acid (malur) undergoes cyclodehydration under favourable conditions, as expected, to giveN-carbamyl maleimide.N-(Carboxymethyl) maleamic acid (malgly), however, does not undergo a similar cyclization reaction. Strong π bonding between the C and N of the amide group as well as two intramolecular hydrogen bonds makesmalglya planar molecule, as revealed by single-crystal X-ray studies.

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3,3′-N,N′-Bis(amino)-2,2′-bipyridine — An unusually methylation-resistant amine

Canadian Journal of Chemistry ◽

10.1139/v11-066 ◽

2011 ◽

Vol 89 (8) ◽

pp. 971-977

Author(s):

Danielle M. Chisholm ◽

Robert McDonald ◽

J. Scott McIndoe

Keyword(s):

Crystal Structure ◽

Hydrogen Bonds ◽

Complex Mixtures ◽

Amino Groups ◽

Intramolecular Hydrogen Bonds ◽

X Ray ◽

Intramolecular Hydrogen

Methylation of aromatic amino groups is usually straightforward, but the formation of two intramolecular hydrogen bonds in 3,3′-N,N′-bis(amino)-2,2′-bipyridine and (or) the potential for ring methylation prevents the clean tetramethylation of this molecule. Numerous attempts to make 3,3′-N,N′-bis(dimethylamino)-2,2′-bipyridine produced only complex mixtures of variously methylated products, and the only isolated molecule was 3,3′-N,N′-bis(methylamino)-2,2′-bipyridine, for which an X-ray crystal structure was obtained.

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Spectral, Thermal, Crystal Structure, Hirshfeld Surface Analyses and Biological Activities of New Hydrazinium Dipicolinato Copper(II) Tetrahydrate

Asian Journal of Chemistry ◽

10.14233/ajchem.2019.21958 ◽

2019 ◽

Vol 31 (8) ◽

pp. 1755-1761

Author(s):

K. Naresh ◽

B.N. Sivasankar

Keyword(s):

Crystal Structure ◽

Hydrogen Bonds ◽

Single Crystal ◽

Water Clusters ◽

Hirshfeld Surface ◽

Water Molecules ◽

X Ray ◽

Biological Studies ◽

Calf Thymus ◽

Hydrazinium Cation

A new copper complex of pyridine-2,6-dicarboxylate containing hydrazinium cation, formulated as (N2H5)2[Cu(PDC)2]·4H2O (PDC = pyridine-2,6-dicarboxylate) has been synthesized from copper(II) nitrate, hydrazine hydrate and pyridine-2,6-dicarboxylic acid as a single crystal and characterized by elemental analysis and spectroscopic (IR and UV-visible), thermal (TG/DTG), single crystal X-ray diffraction and biological studies. A six-coordinate complex with a distorted octahedral geometry around Cu(II) ion is proposed and confirmed by X-ray single crystal method. The structure reveals that two pyridine-2,6-dicarboxylate species acting as tridentate ligands and hydrazinium cation present as a counter ion along with non-coordinated four water molecules. The structural units of copper(II) is mutually held by the hydrogen bonds and π···π and C–O···π interactions. The copper(II) complex is connected to one another via O–H···O hydrogen bonds, forming water clusters, which plays an important role in the stabilization of the crystal structure. In the water clusters, the water molecules are trapped by the cooperative association of coordination interactions as well as hydrogen bonds. Both cation and anion interactions and crystal from various types of intermolecular contacts and their importance were explored using Hirshfeld surface analysis. This indicates that O···H/H···O interactions are the superior interactions conforming excessive H-bond in the molecular structure. The interaction of copper(II) complex with calf thymus DNA (CT-DNA) was investigated by electronic absorption spectroscopic technique. The electronic evidence strongly shows that the compound interacts with calf thymus through intercalation with a binding constant of Kb = 5.7 × 104 M–1.

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Intramolecular hydrogen bonds in chelating agents of the aminocarboxylic acid series (according to data from X-ray diffraction investigations) (review)

Journal of Structural Chemistry ◽

10.1007/bf00751741 ◽

1986 ◽

Vol 27 (2) ◽

pp. 291-314

Author(s):

L. M. Shkol'nikova ◽

M. A. Porai-Koshits ◽

N. M. Dyatlova

Keyword(s):

Hydrogen Bonds ◽

Chelating Agents ◽

X Ray Diffraction ◽

Intramolecular Hydrogen Bonds ◽

X Ray ◽

Aminocarboxylic Acid ◽

Intramolecular Hydrogen

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Heterocyclic Tautomerism. II. 4-Acylpyrazolones. X-Ray Crystal Structures of 4-Benzoyl-5-methyl-2-phenylpyrazol-3(2H)-one and 4-Acetoacetyl-3-methyl-1-phenylpyrazol-5-ol

Australian Journal of Chemistry ◽

10.1071/ch9850401 ◽

1985 ◽

Vol 38 (3) ◽

pp. 401 ◽

Cited By ~ 35

Author(s):

MJ O'Connell ◽

CG Ramsay ◽

PJ Steel

Keyword(s):

Hydrogen Bonds ◽

Crystal Structures ◽

Room Temperature ◽

Crystalline Form ◽

Intermolecular Hydrogen Bonds ◽

Intramolecular Hydrogen Bonds ◽

X Ray ◽

Intramolecular Hydrogen

The colourless crystalline form of the benzoylpyrazolone (2) has molecules with the NH structure (2c) stabilized by intermolecular hydrogen bonds. At room temperature crystals are monoclinic: P21/c, a 13.508(5), b 9.124(4), c 11.451(3)Ǻ, β 90.80(3)°, Z4; the structure was refined to R 0.059, Rw 0.048. The acetoacetylpyrazolone (3) has the OH structure (3c) with two intramolecular hydrogen bonds. At 193 K crystals are triclinic: Pī , a 7.142(2), b 13.704(8), c 14.699(7)Ǻ, α 117.36(3), β 96.87(3), γ 93.73(3)°, Z 4; the structure was refined to R 0.049, Rw 0.054.

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A novel сalcium trifluoroacetate structure

Тонкие химические технологии ◽

10.32362/2410-6593-2021-16-4-352-362 ◽

2021 ◽

Vol 16 (4) ◽

pp. 352-362

Author(s):

A. A. Vasilyeva ◽

T. Yu. Glazunova ◽

D. S. Tereshchenko ◽

E. Kh. Lermontova

Keyword(s):

Thermal Decomposition ◽

Hydrogen Bonds ◽

Trifluoroacetic Acid ◽

Calcium Fluoride ◽

X Ray Diffraction ◽

Absorption Bands ◽

Intramolecular Hydrogen Bonds ◽

X Ray ◽

Cell Parameters ◽

Intramolecular Hydrogen

Objectives. The study was devoted to considering the features of the synthesis and crystal structure of calcium trifluoroacetate Ca2(CF3COO)4·8CF3COOH and investigating the products of its thermal behavior.Methods. The compositions of the proposed structural form were characterized by various physicochemical methods (X-ray diffraction, IR spectroscopy), and the products of thermal decomposition were determined under dynamic vacuum conditions.Results. The reaction between calcium carbonate and 99% trifluoroacetic acid yielded a new structural type of calcium trifluoroacetate Ca2(CF3COO)4·8CF3COOH (I) in the form of colorless prismatic crystals unstable air. X-ray diffraction results confirmed the composition I: space group P21, with unit cell parameters: a = 10.0193(5) Å, b = 15.2612(7) Å, c = 16.3342(8) Å, β = 106.106(2)°, V = 2399.6(2) Å3, Z = 2. The structure is molecular, constructed from Ca2(CF3COO)4·8CF3COOH dimers. The end molecules of the trifluoroacetic acid were involved in the formation of intramolecular hydrogen bonds with oxygen atoms of the bidentate bridging anions CF3COO−. There were strongly pronouncedsymmetric and asymmetric absorption bands of COO and CF3-groups in the IR spectrum of the resulting compound in the range of 1200–1800 cm−1. The definite peak of the oscillation of the OH-group at 3683 cm−1 corresponds to the trifluoroacetic acid molecules present in the structure. The broadpeak of the valence oscillations in the range of 3300–3500 cm−1 is caused by the presence of intramolecular hydrogen bonds. Decomposition began at 250°C and 10−2 mm Hg with calcium fluoride CaF2 as the final decomposition product.Conclusions. We obtained a previously undescribed calcium–trifluoroacetic acid complex whose composition can be represented by Ca2(CF3COO)4·8CF3COOH. The crystal island structure is a dimeric molecule where the calcium atoms are bound into dimers by four trifluoroacetate groups. The complex was deposited in the Cambridge Structural Data Bank with a deposit number CCDC 2081186. Although the compound has a molecular structure, thermal decomposition leads to the formation of calcium fluoride characterized by a small particle size, which may further determine its applications.

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Unusual Effects of Intramolecular Hydrogen Bonds and Dipole Interaction on FTIR and NMR of Some Imines

Asian Journal of Applied Chemistry Research ◽

10.9734/ajacr/2019/v3i330096 ◽

2019 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Elham Abdalrahem Bin Selim ◽

Mohammed Hadi Al–Douh

Keyword(s):

Hydrogen Bonds ◽

Chemical Shifts ◽

Dipole Interaction ◽

Intramolecular Hydrogen Bonds ◽

X Ray ◽

X Ray Crystallography ◽

Dipole Interactions ◽

Intramolecular Hydrogen

Unusual effects of intramolecular hydrogen bonds and dipole interactions are investigated using FTIR, NMR and X-Ray crystallography analyses of some imines. These phenomena affect both FTIR absorptions and chemical shifts.

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Structural and spectroscopic studies of dipotassium 3,3,3′,3′-tetramethylcystinate trihydrate, K2[C10H18N2O4S2]3H2O

Canadian Journal of Chemistry ◽

10.1139/v84-186 ◽

1984 ◽

Vol 62 (6) ◽

pp. 1127-1133 ◽

Cited By ~ 3

Author(s):

Romolo Faggiani ◽

Helen Elaine Howard-Lock ◽

Colin James Lyne Lock ◽

Maria Lurdes Martins ◽

Philip Stuart Smalley

Keyword(s):

Hydrogen Bonds ◽

Single Crystal ◽

Spectroscopic Studies ◽

The Other ◽

Ionic Interactions ◽

Water Molecules ◽

Torsional Angle ◽

X Ray Diffraction ◽

Standard Methods ◽

X Ray

The compound dipotassium 3,3,3′,3′-tetramethylcystinate trihydrate, K2[C10H18O4N2S2]3H2O, has been prepared and characterized by single crystal X-ray diffraction. Crystals were monoclinic, P21a = 6.160(1), b = 26.473(8), c = 6.193(1) Å, β = 113.94(1)°, with two formula units in the unit cell. Intensities were measured on a Syntex P21, diffractometer with use of MoKα radiation. The structure was solved by standard methods and refined to R1 = 0.0469, R2 = 0.0472 based on 2303 independent observed reflections. The C—S bonds (1.877(6), 1.891(6) Å) are longer than in many similar compounds although the S—S bond (2.040(2) Å) is not. The C—S—S—C torsional angle (108.7(3)°) is larger than normal in dithiol compounds. Other distances and angles are normal. Two types of potassium coordination are present, one a distorted octahedron, the other a distorted trigonal prism. In addition to the ionic interactions, hydrogen bonds involving the water molecules are important in stabilizing the structure.

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Dirubidium hexaaquacobalt(II) tetrakis(hydrogen phthalate) tetrahydrate and coordination modes of the hydrogen phthalate anion

Acta Crystallographica Section C Crystal Structure Communications ◽

10.1107/s0108270113016788 ◽

2013 ◽

Vol 69 (8) ◽

pp. 841-846 ◽

Cited By ~ 1

Author(s):

Dejan Poleti ◽

Jelena Rogan

Keyword(s):

Hydrogen Bonds ◽

Crystal Packing ◽

Outer Part ◽

Water Molecules ◽

Hydrogen Phthalate ◽

Aromatic Rings ◽

Intramolecular Hydrogen Bonds ◽

Coordination Modes ◽

Bonding Interaction ◽

Intramolecular Hydrogen

The title compound, Rb2[Co(H2O)6](C8H5O4)4·4H2O, consists of nearly regular octahedral [Co(H2O)6]2+cations with the CoIIcations on the inversion centre (special position 2a), Rb+cations, hydrogen phthalate (Hpht−) anions and disordered water molecules. The Rb+cation is surrounded by nine O atoms from Hpht−anions and water molecules, with a strongly deformed pentagonal–bipyramidal geometry and one apex split into three positions. The crystal packing is governed by numerous hydrogen bonds involving all water molecules and Hpht−anions. In this way, layers parallel to theabplane are formed, with the aromatic rings of the Hpht−anions esentially directed along thecaxis. While Hpht−anions form the outer part of the layers, disordered water molecules and Rb+cations alternate with [Co(H2O)6]2+cations in the inner parts. The only interactions between the layers are van der Waals forces between the atoms of the aromatic rings. A search of the Cambridge Structural Database for coordination modes and types of hydrogen-bonding interaction of the Hpht−anion showed that, when uncoordinated Hpht−anions are present, compounds with intermolecular hydrogen bonds are more numerous than compounds with intramolecular hydrogen bonds. For coordinated Hpht−anions, chelating and bridging anions are almost equally common, while monodentate anions are relatively scarce. The same coordination modes appear for Hpht−anions with or without intramolecular hydrogen bonds, although intramolecular hydrogen bonds are less common.

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