Structural Characteristics of Aryloxybismuthanes Stabilized by Hypervalent Bond Formation. Synthesis, Incorporation of 4-Methoxyphenol through Hydrogen Bonding, and Crystal Supramolecularity

2000 ◽  
Vol 19 (6) ◽  
pp. 1003-1007 ◽  
Author(s):  
Toshihiro Murafuji ◽  
Masahiro Nagasue ◽  
Yoshihiro Tashiro ◽  
Yoshikazu Sugihara ◽  
Nagao Azuma
Keyword(s):  
Hydrogen Bonding ◽  
Structural Characteristics ◽  
Bond Formation ◽  
Crystal Supramolecularity

A hexaniobate expanded by six [Hg(cyclam)]2+ complexes via Hg–O bonds yields a positively charged polyoxoniobate cluster

2020 ◽  
Vol 75 (1-2) ◽  
pp. 233-237 ◽  
Author(s):  
Philipp Müscher-Polzin ◽  
Christian Näther ◽  
Wolfgang Bensch
Keyword(s):  
Hydrogen Bonding ◽  
Title Compound ◽  
Room Temperature ◽  
Bond Formation ◽  
Water Molecules ◽  
The Novel ◽  
Temperature Reaction ◽  
Crystal Water ◽  
Nitrate Anions ◽  
Positively Charged

AbstractThe room temperature reaction of Hg(NO3)2 · H2O, cyclam (cyclam = 1,4,8,11-tetraazacyclotetradecane) and K8{Nb6O19} · 16 H2O in a mixture of H2O and DMSO led to crystallization of the novel compound {[Hg(cyclam)]6Nb6O19}(NO3)4 · 14 H2O, which is the first mercury containing polyoxoniobate. The structure consists of a {Nb6O19}8− cluster core which is expanded by six [Hg(cyclam)]2+ complexes via Hg–μ2-O–Nb bond formation. The title compound contains a positively charged polyoxoniobate cluster. The crystal water molecules form small aggregates by O–H · · · O hydrogen bonding which are joined into larger aggregates by N–O · · · H–O hydrogen bonding integrating the nitrate anions.

Enthalpies of hydrogen bond formation of 1-octanol with aprotic organic solvents. A comparison of the solvation enthalpy, pure base, and non-hydrogen-bonding baseline methods

1985 ◽  
Vol 63 (2) ◽  
pp. 342-348 ◽  
Author(s):  
W. Kirk Stephenson ◽  
Richard Fuchs
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Bond Formation ◽  
Enthalpies Of Solution ◽  
Dispersion Interactions ◽  
Butyl Ether ◽  
Hydrogen Bond Formation ◽  
Solvation Enthalpy ◽  
Benzene Toluene ◽  
Good Agreement

Enthalpies of solution (ΔHs) of 1-octanol and five model compounds (di-n-butyl ether, n-heptyl methyl ether, 1-fluoro-octane, 1-chlorooctane, and n-octane) have been determined in 13 solvents (heptane, cyclohexane, CCl4, 1,1,1-trichloro-ethane, 1,2-dichloroethane, triethylamine, butyl ether, ethyl acetate, DMF, DMSO, benzene, toluene, mesitylene), and combined with heats of vaporization to give enthalpies of transfer from vapor to solvent (ΔH(v → S)). These values have been used to calculate the enthalpy of hydrogen bond formation (ΔHh) of 1-octanol with each solvent, using the pure base (PB), solvation enthalpy (SE), and non-hydrogen-bonding baseline (NHBB) methods. Evidence is presented suggesting that (a) the SE method is susceptible to mismatches of the 1-octanol vs. model polar and dispersion interactions, (b) the PB method is sensitive to polar interaction mismatches, whereas (c) the NHBB method compensates for both polar and dispersion interactions mismatches. The (apparent) ΔHh values determined by the SE and PB methods may be as much as several kcal/mol (nearly 50%) too large, because of the inclusion of other polar and dispersion interactions. The NHBB method is therefore preferred for determining enthalpies of H-bond formation from calorimetric data. However, apparent ΔHh values from the SE and PB methods can be incorporated into total solvatochromic equations using Taft–Kamiet π*, β, and ξ parameters, to provide enthalpies of H-bond formation in good agreement with ΔHh (NHBB).

scholarly journals Unique Digoldgermanes: Structural Characteristics, Dynamic Behaviour and Distinctive Reactions

2021 ◽  
Author(s):  
Liliang Wang ◽  
Guorong Zhen ◽  
Yinhuan Li ◽  
Mitsuo Kira ◽  
Liping Yan ◽  
...  
Keyword(s):  
Dft Calculations ◽  
Dynamic Behaviour ◽  
Structural Characteristics ◽  
Bond Formation ◽  
Gold Atom ◽  
Addition Product ◽  
X Ray ◽  
Ambient Temperatures ◽  
X Ray Crystallography ◽  
H Nmr

Abstract Digoldgermanes with a gold coordinated by a dialkylgermylene ligand, R’2Ge(AuPR3)(AuGeR’2) (3a; R = Me, 3b; R = Et), were synthesized as green solids through the reactions of stable dialkylgermylene 1 with R3PAuCl followed by the reduction with KC8 at ambient temperatures. The structural characteristics of 3a and 3b were elucidated using NMR spectroscopy, X-ray crystallography, and DFT calculations. An intense absorption maximum was observed at 590 nm in the UV-vis spectrum of 3a in hexane. A pendular motion of AuPR3 group between Ge(IV) and Ge(II) of 3a and 3b occurring in the NMR time scale was found by the dynamic 1H NMR analysis, suggesting that the Ge(II) ligand has an enhanced electrophilicity to be attacked by the nucleophilic gold atom which closes to ‒1 oxidation state. DFT calculations of 3a revealed the existence of high-lying σ(Ge-Au) type HOMO and low-lying LUMO with germylene pπ nature. We show the bond formation and activation alternatively at Au or Ge atom, a methylation of digoldgermane 3a with MeOTf affords methylgermane 5. Moreover, the digoldgermane 3a reacts with Cl− ion of Ph4PCl and CH3C(O)Cl smoothly to form the corresponding chloride-addition product 7 and chlorogoldgermane 9, respectively. Cyclic trimerization reactions of aromatic isocyanates were high-efficiently catalyzed by 3a giving the corresponding 1,3,5-triaryl isocyanurates.

Anharmonicity, solvent effects, and hydrogen bonding: NH stretching vibrations

1970 ◽  
Vol 48 (14) ◽  
pp. 2197-2203 ◽  
Author(s):  
A. Foldes ◽  
C. Sandorfy
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Solvent Effects ◽  
Bond Formation ◽  
Hydrogen Bond Formation ◽  
Stretching Vibration ◽  
Solvent Shifts ◽  
Stretching Vibrations ◽  
Secondary Amides ◽  
Influence Of Solvent

The influence of solvent effects and hydrogen bond formation on the anharmonicity of the NH stretching vibration of simple secondary amides, lactams, anilides, indole, pyrrole, and imidazole have been studied; and the frequencies of the first and second overtones, their half widths and solvent shifts measured. The validity of Buckingham's theory is established in the case of inert solvents; whereas the second order perturbation treatments are shown to be inapplicable to the case of hydrogen bonding solvents. All NH stretching modes seem to exhibit the same anharmonic behavior which is very different from that of OH vibrations.

Dynamics of the chemical bond: inter- and intra-molecular hydrogen bond

2015 ◽  
Vol 177 ◽  
pp. 51-64 ◽  
Author(s):  
Elangannan Arunan ◽  
Devendra Mani
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Molecular Hydrogen ◽  
Theoretical Calculations ◽  
Bond Formation ◽  
Chem Phys ◽  
Equilibrium Structure ◽  
Molecular Hydrogen Bond ◽  
Mode Vibration ◽  
Definition Of

In this discussion, we show that a static definition of a ‘bond’ is not viable by looking at a few examples for both inter- and intra-molecular hydrogen bonding. This follows from our earlier work (Goswami and Arunan,Phys. Chem. Chem. Phys.2009,11, 8974) which showed a practical way to differentiate ‘hydrogen bonding’ from ‘van der Waals interaction’. We report results fromab initioand atoms in molecules theoretical calculations for a series of Rg⋯HX complexes (Rg = He/Ne/Ar and X = F/Cl/Br) and ethane-1,2-diol. Results for the Rg⋯HX/DX complexes show that Rg⋯DX could have a ‘deuterium bond’ even when Rg⋯HX is not ‘hydrogen bonded’, according to the practical criterion given by Goswami and Arunan. Results for ethane-1,2-diol show that an ‘intra-molecular hydrogen bond’ can appear during a normal mode vibration which is dominated by the O⋯O stretching, though a ‘bond’ is not found in the equilibrium structure. This dynamical ‘bond’ formation may nevertheless be important in ensuring the continuity of electron density across a molecule. In the former case, a vibration ‘breaks’ an existing bond and in the later case, a vibration leads to ‘bond’ formation. In both cases, the molecule/complex stays bound irrespective of what happens to this ‘hydrogen bond’. Both these cases push the borders on the recent IUPAC recommendation on hydrogen bonding (Arunanet al. Pure. Appl. Chem.2011,831637) and justify the inclusive nature of the definition.

Synthesis and characterization of a cadmium(II)–organic supramolecular coordination compound based on the multifunctional 2-amino-5-sulfobenzoic acid ligand

2016 ◽  
Vol 72 (12) ◽  
pp. 939-946 ◽  
Author(s):  
Gan-Yin Yuan ◽  
Lei Zhang ◽  
Meng-Jie Wang ◽  
Kou-Lin Zhang
Keyword(s):  
Hydrogen Bonding ◽  
Solid State ◽  
Coordination Compound ◽  
Coordination Compounds ◽  
Structural Characteristics ◽  
Three Dimensional ◽  
Distorted Octahedral Geometry ◽  
Two Dimensional ◽  
Ambient Conditions ◽  
Supramolecular Coordination

Much attention has been paid by chemists to the construction of supramolecular coordination compounds based on the multifunctional ligand 5-sulfosalicylic acid (H3SSA) due to the structural and biological interest of these compounds. However, no coordination compounds have been reported for the multifunctional amino-substituted sulfobenzoate ligand 2-amino-5-sulfobenzoic acid (H2asba). We expected that H2asba could be a suitable building block for the assembly of supramolecular networks due to its interesting structural characteristics. The reaction of cadmium(II) nitrate with H2asba in the presence of the auxiliary flexible dipyridylamide ligandN,N′-bis[(pyridin-4-yl)methyl]oxamide (4bpme) under ambient conditions formed a new mixed-ligand coordination compound, namely bis(3-amino-4-carboxybenzenesulfonato-κO1)diaquabis{N,N′-bis[(pyridin-4-yl)methyl]oxamide-κN}cadmium(II)–N,N′-bis[(pyridin-4-yl)methyl]oxamide–water (1/1/4), [Cd(C7H6NO5S)2(C14H14N4O2)2(H2O)2]·C14H14N4O2·4H2O, (1), which was characterized by single-crystal and powder X-ray diffraction analysis (PXRD), FT–IR spectroscopy, thermogravimetric analysis (TG), and UV–Vis and photoluminescence spectroscopic analyses in the solid state. The central CdIIatom in (1) occupies a special position on a centre of inversion and exhibits a slightly distorted octahedral geometry, being coordinated by two N atoms from two monodentate 4bpme ligands, four O atoms from two monodentate 4-amino-3-carboxybenzenesulfonate (Hasba−) ligands and two coordinated water molecules. Interestingly, complex (1) further extends into a threefold polycatenated 0D→2D (0D is zero-dimensional and 2D is two-dimensional) interpenetrated supramolecular two-dimensional (4,4) layer through intermolecular hydrogen bonding. The interlayer hydrogen bonding further links adjacent threefold polycatenated two-dimensional layers into a three-dimensional network. The optical properties of complex (1) indicate that it may be used as a potential indirect band gap semiconductor material. Complex (1) exhibits an irreversible dehydration–rehydration behaviour. The fluorescence properties have also been investigated in the solid state at room temperature.

Hydrogen bonding of n-alcohols of different chain lengths

1985 ◽  
Vol 63 (1) ◽  
pp. 40-45 ◽  
Author(s):  
Lucie Wilson ◽  
R. Bicca de Alencastro ◽  
C. Sandorfy
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Chain Length ◽  
Bond Formation ◽  
Hydrocarbon Chain ◽  
Hydrogen Bond Formation ◽  
Degree Of Association ◽  
Chain Lengths ◽  
Anesthetic Potency

The anesthetic potency of n-alcohols exhibits a somewhat irregular dependence on the length of the hydrocarbon chain. An attempt has therefore been made to ascertain if this is related to the relative tendency for hydrogen bond formation by these alcohols. No such relationship was found. The result was rather that the degree of association by hydrogen bond formation of dissolved alcohols appears to be independent of the chain length, that is of the extent of other interactions that exist in these solutions.

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