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The synthesis of four novel amide compounds (R1C(O)NHR2) is reported, which contain both bulky (R1=phenyl and adamantyl) and hydrophilic (R2=hydroxyl, methoxyl) groups. The incorporation of such substituents provides compounds with unique properties that combine steric hindrance and hydrophilicity. The synthesized amides were fully characterized by 1H and 13C nuclear magnetic resonance (NMR) and analysed using infrared (IR) and Raman spectroscopy to investigate their vibrational properties in the solid phase, specifically focusing on the amide‐type normal modes of vibrations. Furthermore, the crystal structures of three derivatives were determined by single‐crystal X‐ray diffraction, which provided insights into their molecular arrangements. The occurrence of N−H⋅⋅⋅O=C hydrogen bonding intermolecular interaction is clearly observed and characterized by Hirschfeld surface analysis. Topology analysis using the Quantum Theory of Atom in Molecules and Crystals (QTAIM−C) were employed to investigate the electronic properties of the isolated amide molecules and to analyse the intermolecular interactions within the crystalline structure. The periodic calculations for the crystal revealed a higher electronic density in the C−N bond, indicating an increased covalent character in this bond compared with the C=O bond. This observation indicates the presence of resonance‐assisted hydrogen bonds within the amide core, leading to π electronic delocalization. [ABSTRACT FROM AUTHOR]

The structure of two perhalomethylated chromones, 2‐chlorodifluoromethylchromone (a) and its 6‐nitro substituted derivative (b), are investigated. The supramolecular assembly is governed by the hydrogen bond interaction (C−H···O) between the olefinic proton (OC−C(=C<)‐H) and the carbonyl oxygen atom (>C=O) giving rise to center‐symmetric R22(8)$R_2^2(8)$ graph‐set motifs. The H···O interatomic distance is shorter in (b) suggesting a stronger hydrogen bonding for this derivative. Quantum Theory of Atoms in Molecules (QTAIM) and natural bond orbital (NBO) calculated energies and the higher polarity computed for (b) agree with this experimental finding. The Molecular Electrostatic Potential (MEP) graph shows a distinctive C···Cl contact, found only for (b), involving a more electrophilic methine carbon atom. [ABSTRACT FROM AUTHOR]

The crystal structures of bis[1-ethyl-6-fluoro-4-oxo-7-(piperazin-1-ium-4-yl)-1,4- dihydroquinoline-3-carboxylato]copper(II) sulfate heptahydrate, [Cu(C16H18FN3O3) 2]SO4.7H2O or [Cu(nor)2]SO4.7H2O (nor is norfloxacin), and bis{1-[2- (ethylsulfonyl)ethyl]-2-methyl-5-nitroimide}dinitratocopper(II), [Cu(NO3)2- (C8H13N3O4S)2] or [Cu(NO3)2(tnz)2] (tnz is tinidazole), were solved by X-ray diffraction. Both complexes crystallize in the space group P21/c, with Z = 4 (for nor) and Z = 2 (for ntz) molecules per unit cell. In [Cu(nor)2]SO4.7H2O, the CuII ion is at the centre of a square-planar environment, trans coordinated to two independent norfloxacin molecules in the zwitterionic form acting as bidentate ligands through one of the carboxyl (cbx) and the carbonyl (cb) O atoms. The solid is further stabilized by an extensive network of N--H. . .O(sulfate), N--H. . .O(cbx), N--H. . .OW, OW--H. . .O(sulfate) and OW--H. . .OW hydrogen bonds. The [Cu(NO3)2(tnz)2] complex is centrosymmetric, with the CuII ion in a square planar environment, coordinated to a tinidazole molecule acting as a monodentate ligand through its imidazole N atom and to one nitrate O atom. The vibrational FT-IR absorption spectra and thermal behaviour of the complexes were also studied and are briefly discussed based on the crystal structures. [ABSTRACT FROM AUTHOR]

An efficient synthesis of new 1‐O‐β‐glycosylmethyl isoxazoles is described. The title compounds are obtained by cycloaddition of nitrile oxides generated in situ in 2‐MeTHF/sodium hypochlorite solution. The developed approach provides the first use of this green methodology to prepare isoxazole derivatives. X‐ray diffraction structure and conformational analysis in solution show that glycosyl isoxazoles possess the structural features required to be substrates of GLUT‐1. [ABSTRACT FROM AUTHOR]

A new perfluoromethylated vinylogous amide, (Z)‐4,4,4‐trifluoro‐1‐(2‐hydroxyphenyl)‐3‐(2‐methoxyethylamino)‐2‐buten‐1‐one, is chosen as an example to investigate the bonding interactions in solid state. The Z, s‐cis form is the dominant conformation in both solution and solid state. Intramolecular hydrogen bonding determines this conformational preference in a nonpolar solvent (NMR spectra). Carbonyl and phenol groups are sensitive to the intra‐ and intermolecular contacts (vibrational spectra). The supramolecular assembly (X‐ray diffraction) is governed by NH⋯O and OH⋯O strong intermolecular hydrogen bonds giving rise to center‐symmetric R22(16) and R22(12) graph‐set motifs. The π‐stacking, F⋯H and F⋯F interactions are also discussed (Hirshfeld analysis). [ABSTRACT FROM AUTHOR]

M(II) complexes with sulfadiazine (SDZ) and imidazole (Im) acting as co‐ligand, [M(SDZ)2(Im)2] (M=Co, Ni, Cu and Zn), have been synthesized and characterized. The crystal structure of Co(II) complex (1) is reported, and a similar structure for the other three complexes is inferred by elemental analysis, IR and electronic spectra. The Co(II) complex is stabilized by intermolecular N–H⋅⋅⋅N, N–H⋅⋅⋅O and C–H⋅⋅⋅O hydrogen bonds, as well as C–H⋅⋅⋅π interactions. An investigation of those structural motifs via Hirshfeld surface analysis has been performed. Energy framework calculations have been carried out to analyze and visualize the 3D topology of the crystal assembly, indicating that the electrostatic energy is dominant over the dispersion one in the most energetic dimer (Motif 1), unlike two related cobalt‐sulfadiazine complexes with other co‐ligands where the dispersion component is more relevant. Further, the relative strength of the bifurcated N–H⋅⋅⋅N/O hydrogen bonds has been analyzed using the quantum theory of "atoms‐in‐molecules" (QTAIM) and molecular electrostatic potential (MEP) surface calculations. The strongest H‐bonds occurring with donor groups from co‐ligand species (Im, DMF and CH3OH) are found to be imperative in controlling the supramolecular architecture of the corresponding cobalt complex. [ABSTRACT FROM AUTHOR]

We present the selective synthesis of novel aminooxy glycosyl derivatives bearing hydroxy phenyl moieties. A strict control over the anomeric and E/Z configurations has been achieved. The products obtained are α‐glycosides and the aromatic moiety substitute the Schiff's base trans to the O‐glycosidic bond. Single crystal X‐ray diffraction and NMR spectral data are reported and analysed. [ABSTRACT FROM AUTHOR]

Abstract: The accumulation of radical anions from 3,4‐disubstituted 1,2,5‐thiadiazole S,S‐dioxides (1) in solution of organic solvents is achieved by electrochemical, chemical and photoinduced pathways. Electrolytic and chemical reduction of 1 produces the radical anions (1•–) in high molar yields (> ca. 80%). The survival of 1•– is measured for ca. three months. The stability of the reduced state depends on its structure and the composition (solvent, reducing agent, and supporting electrolyte) of the medium in which it is generated by the chemical and electrochemical routes. In solution of polar aprotic solvents, 1•– persists even in the presence of water or oxygen. Irradiation with 254 nm light generates 1•– but only in DMF solution; the proposed reaction mechanism involves the participation of the solvent. Radical anions are characterized by cyclic voltammetry, UV‐Vis spectrophotometry and electron spin resonance spectroscopy. The chemical stability and the properties of 1/1•– make them suitable for the development of novel materials for technological applications. [ABSTRACT FROM AUTHOR]

A reference to the prior publication of one of the crystal structures reported by Tobón‐Zapata [Acta Cryst. (2022), B78, 490–498] is given. [ABSTRACT FROM AUTHOR]

A new water-soluble complex, Re(CO)3(pterin)(H2O), was synthesized and characterized by 1H NMR and FTIR spectroscopy, and by a combination of three mass spectrometry techniques: MALDI, probe electrospray ionisation (PESI), and ESI. Because, unlike most metal-pterin complexes, the ReI complex is quite soluble in water, appropriate single crystals could be obtained for structural X-ray analysis. We report here the first solid state molecular structure containing a pterin ligand coordinated to the Re(CO)3 core. This determination revealed that strong H bonds between the hydrogen atom of the 2-amino group and crystallization water molecules give rise to a polymeric arrangement of Re(CO)3(pterin)(H2O) complexes in the lattice. Protonation studies in aqueous solutions of the ReI complex showed two acid-base equilibriums with p Ka1 = 3.9 and p Ka2 = 8.8. p Ka1 was assigned to the protonation equilibrium at N3 of the pterin ligand in the complex and p Ka2 could be ascribed to the deprotonation of a coordinated water molecule. [ABSTRACT FROM AUTHOR]

In this study 2-(2′-furyl)-4,5-1H-dihydroimidazole (1) was prepared and then characterized by infrared, Raman, and multidimensional nuclear magnetic resonance (NMR) spectroscopies. The crystal and molecular structures of 1 were determined by X-ray diffraction methods. The density functional theory (DFT) and second-order Møller–Plesset theory (MP2) with Pople's basis set show that there are two conformers for the title molecule that have been theoretically determined in the gas phase, and that only one of them, conformer I, is present in the solid phase. NMR spectra observed for 1 were successfully compared with the calculated chemical shifts at the B3LYP/6-311++G** level theorized for this conformer. The harmonic vibrational frequencies for the optimized geometry of the latter conformer were calculated at the B3LYP/6-311++G** level in the approximation of the isolated molecule. For a complete assignment of the IR and Raman spectra in the solid phase of 1, DFT calculations were combined with Pulaýs scaled quantum mechanics force field (SQMFF) methodology to fit the theoretical frequency values to the experimental ones. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

α-diamines, such as ethylendiamine and o-phenylendiamine, add to 3,4-aryl-disubstituted 1,2,5-thiadiazole 1,1-dioxides to give dihydropyrazines or quinoxalines, respectively and sulfamide. The new compound acenaphtho [5,6-b]-2,3-dihydropyrazine was synthesized and characterized. The addition of ethylendiamine to 3,4-diphenyl- 1,2,5-thiadiazoline 1,1-dioxide gives 3,4-disubstituted thiadiazolidine 1,1-dioxide, dihydropyrazines, or pyrazines, depending on the reaction condition used. The reactions were followed by cyclic voltammetry and NMR spectroscopy which, in some cases, allowed the detection of the thiadiazolidine intermediate. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The first nucleophilic addition of an inorganic nucleophile (cyanide) to the activated, rigid, α-diazomethine groups of a 1,2,5-thiadiazole 1,1-dioxide is reported here. An α-amino nitrile and a bis α-amino nitrile derivatives were obtained in good yields (62 and 98%, respectively) and characterized by spectroscopic, analytical, and single crystal X-ray diffraction techniques. The course of the reaction, followed by cyclic voltammetry (CV), showed that cyanide adds to only one of the two C&dbond;N double bonds of the thiadiazole, forming an anion from which an N-methyl derivative was obtained. Adequate concentrations of cyanide and methyl iodide (MeI) produced directly the bis α-amino nitrile derivative. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The reactions of n-butylamine (BuNH2), 2-aminoethanol (H2N(CH2)2OH), diethylamine (Et2NH), and phenylhydrazine (PhN2H3) with 3,4-diphenyl-(1a) and phenanthro[9,10-c]-1,2,5-thiadiazole 1,1-dioxide (1b) were studied by cyclic voltammetry (CV) and 1H- and 13C-NMR in aprotic solvent solution. The course of the reactions depended on the substrate-nucleophile combination: Et2NH added to 1a or 1b, forming the corresponding thiadiazolines in an equilibrium monoaddition reaction. The equilibrium constants were evaluated and compared. With primary amines and PhN2H3, the nucleophile added to both C&dbond;N double bonds of 1a and displaced the sulfamide moiety. In the case of the reaction of 1a with PhN2H3, the intermediate monoaddition thiadiazoline, 3-(2-phenylhydrazino)-3,4-diphenyl-1,2,5-thiadiazoline 1,1-dioxide, was also isolated. BuNH2 and H2N(CH2)2OH reacted with 1a to give α-bis-imines, while 1a with PhN2H3 gave the α-bis-hydrazone. The configurations of benzil bis(ethanolimine) and benzilosazone were determined by single crystal x-ray diffraction analysis as Z,Z. BuNH2 and PhN2H3 reduced 1b to the corresponding thiadiazoline compound 1bH2. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Dodecylnicotinate bis-adducts of binuclear copper carboxylates, of the general formula Cu2(O2CCn - 1H2n - 1)4(C5H4N-COOC1H25)2, were synthesized for n = 10, 12, 14, 16, 18 and 20, and their crystal structure, thermal behavior and magnetic properties studied. The molecular structure of the decyl derivative has been determined from single-crystal X-ray diffraction data. The dimer is centrosymmetric with the CuII ions in a square-pyramidal coordination with four O-alkyl O atoms [average d(Cu-O) 1.960 (6) Å] in the basal plane and the nicotine N atom at apical positions [d(Cu-N) 2.183 (3) Å]. The copper ions, 1615 (1) Å apart, are bridged by four O-alkyl carboxylate groups. Both the n = 20 and n = 18 homologues exhibit lamellar phases, which can be related to the supramolecular arrangement found in the n = 10 derivative. The magnetic behavior of the decyl and octadecyl dimers was studied in the 2-300 K temperature range. They exhibit a strong intramolecular antiferromagnetic interaction (Cu-Cu superexchange coupling constant J = -347 cm-1 for the decyl derivative), which can be attributed to a large overlap of the metal 3d orbitals and the oxygen lone pair orbitals of the linking carboxylale groups. [ABSTRACT FROM AUTHOR]

The title compound, N-[2-(5-methoxy-1-nitro­so-1 H-indol-3-yl)­ethyl]­acet­amide, C13H15N3O3, an N-nitroso derivative of melatonin, crystallizes in the monoclinic C2/ c space group. The mol­ecules are arranged in such a way that the aromatic rings are in a planar conformation, with the alkyl­amide side chains in a different plane, at a dihedral angle of 108.60 (6)°. The alkyl­amide chains are interconnected by hydrogen bonds, constituting an infinite array. [ABSTRACT FROM AUTHOR]

The title compound is synthesized by addition of solid Tl2CO3 to a boiling solution of H2C2O4 in H2O (10 min, 75% yield) and characterized by single crystal XRD, FTIR, and FT Raman spectroscopy. [ABSTRACT FROM AUTHOR]

The title compound, tetrakis(μ-3,4,5-triethoxy­benzoato-κ2 O: O′)­bis­[(pyrazine-κ N)­rhodium(II)]( Rh-Rh), [Rh2(C13H17O5)4(C4H4N2)2], crystallizes on an inversion centre in the triclinic space group . The equatorial carboxyl­ate ligands bridge the two RhII atoms, giving a binuclear lantern-like structure. The pyrazine mol­ecules occupy the two axial coordination sites. The phenyl rings are tilted by ca 10° with respect to the attached carboxyl­ate groups. The pyrazine planes have a torsion angle of ca 19° around the Rh-N bond with respect to the plane of the nearer carboxyl­ate group and are not coplanar with the Rh-Rh bond. [ABSTRACT FROM AUTHOR]

The crystal structures of two salts of bis­(thio­urea)­gold(I) complexes, namely bis­(thio­urea-κ S)­gold(I) chloride, [Au(CH4N2S)2]Cl, (I), and bis­[bis­(thio­urea-κ S)­gold(I)] sulfate, [Au(CH4N2S)2]2SO4, (II), have been determined. The chloride salt, (I), is isomorphous with the corresponding bromide salt, although there are differences in the bonding. The AuI ion is located on an inversion centre and coordinated by two symmetry-related thio­urea ligands through the lone pairs on their S atoms [Au-S 2.278 (2) Å and Au-S-C 105.3 (2)°]. The sulfate salt, (II), crystallizes with four independent [Au(CH4N2S)2]+ cations per asymmetric unit, all with nearly linear S-Au-S bonding. The cations in (II) have similar conformations to that found for (I). The Au-S distances range from 2.276 (3) to 2.287 (3) Å and the Au-S-C angles from 173.5 (1) to 177.7 (1)°. These data are relevant in interpreting different electrochemical processes where gold-thio­urea species are formed. [ABSTRACT FROM AUTHOR]

The octahedral title compound, [Ru(C2H5O)(NO)(NO2)2(C6H16N2)], crystallizes in the rhombohedral space group P31 with an ethoxy ligand axially coordinated trans to the nitro­syl ligand. The RuII ion is equatorially coordinated by a tetramethylethylenediamine group acting as a bidentate ligand, and to two nitro moieties whose planes are tilted with respect to the mean equatorial plane. Each nitro­gen ligand bonded to the metallic centre has a different hybridization state. [ABSTRACT FROM AUTHOR]

The title compound, catena-poly[[tetrakis(μ-decanoato-κ2 O: O′)diruthenium(II,III)( Ru- Ru)]-μ-octanesulfonato-κ2 O: O′], [Ru2(C10H19O2)4(C8H17O3S)], is an octane­sulfonate derivative of the mixed-valence complex diruthenium tetradecanoate. The equatorial carboxyl­ate ligands are bidentate, bridging two Ru atoms to form a dinuclear structure. Each of the two independent dinuclear metal complexes in the asymmetric unit is located at an inversion centre. The octane­sulfonate anion bridges the two dinuclear units through axial coordination. The alkyl chains of the carboxyl­ate and sulfonate ligands are arranged in a parallel manner. The global structure can be seen as infinite chains of polar moieties separated by a double layer of non-polar alkyl groups, without interdigitation of the alkyl chains. [ABSTRACT FROM AUTHOR]

The octahedral title compound, [Ru(C(2)H(5)O)(NO)(NO(2))(2)(C(6)H(16)N(2))], crystallizes in the rhombohedral space group P3(1) with an ethoxy ligand axially coordinated trans to the nitrosyl ligand. The RuII ion is equatorially coordinated by a tetramethylethylenediamine group acting as a bidentate ligand, and to two nitro moieties whose planes are tilted with respect to the mean equatorial plane. Each nitrogen ligand bonded to the metallic centre has a different hybridization state.