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  • Author: Oscar E. Piro x
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The crystal structure of hexamethylenediammonium bis(thiosaccharinate) dihydrate, [H3N-(CH2)6-NH3](tsac)2 · 2H2O (tsac=C7H4NO2S2, the anion of thiosaccharin), was determined by single-crystal X-ray diffraction. It crystallizes in the monoclinic space group P21/a with Z = 4. The thiosaccharinate moiety is planar and shows small but significant modifications in the bonding of the thioamide functional group as compared with the protonated neutral molecule. The ionic crystal is further stabilized by an extensive H-bonding network, which links the anions and cations into an infinite three-dimensional supramolecular assembly. The FTIR spectrum of the compound is briefly discussed in comparison with those of the neutral constituent molecules.

The crystal structure of [Cu(sac)2(nic)2(H2O)] (sac = saccharinate anion; nic = nicotinamide) has been determined by single-crystal X-ray diffraction. It crystallizes in the monoclinic space group C2/c with Z = 4 and the Cu(II) ion presents a CuN4O square pyramidal coordination. Some comparisons with related structures are made and the most important features of its IR spectrum were also discussed.

Abstract

The crystal structures of [M(nic)2 (H2O)4](sac)2 (nic = nocotinamide; sac = saccharinate anion) with M = Co(II), Ni(II) and Zn(II), have been determined at 116 K by single-crystal X-ray diffractometry. The compounds crystallize in the triclinic space group P1̅ with Z = 1, and the M(II) cations present a slightly distorted MN2O4 octahedral environment, with equatorially coordinated water molecules and axially pyridine N-bound nicotinamide ligands. The saccharinate anions act as counteranions, and are not part of the first coordination sphere. Some comparisons with related structures have been made and the most important features of their IR spectra discussed.

The crystal structures of heptamethylenediammonium bis(saccharinate) monohydrate, [H3N - (CH2)7 -NH3](sac)2・H2O (1) and octamethylenediammonium bis(saccharinate) hemihydrate, [H3N- (CH2)8-NH3](sac)2・0.5H2O (2), were determined by single-crystal X-ray diffraction methods. Compound 1 crystallizes in the triclinic space group P1̄ with 2 molecules per unit cell, and 2 in the monoclinic space group P21/a with Z = 4. The saccharinate moiety is planar in both compounds presenting bonding characteristics comparable to those found in other saccharinate salts. The ionic crystals are further stabilized by an extensive H-bonding network, which links the anions and cations into an infinite three-dimensional supramolecular assembly. The FTIR spectra of the adducts are briefly discussed in comparison with those of the constituent molecules.

The crystal structure of trans-[ReCl2(dppp)2]- Cl · ½H2O (dppp = 1,3-bis(diphenylphosphino)- propane), a potentially useful radiopharmaceutical agent, was determined by single crystal X-ray diffractometry. It belongs to the tetragonal space group P4̄ with Z = 2. The Re(III) ion is in a quasioctahedral environment coordinated to a pair of symmetry related dppp molecules, acting as bidentate ligands, and two axial chloride ions.

The crystal and molecular structure of the [VO(DLmeth)( NH2O)2]・H2O complex has been determined by X-ray diffraction methods (monoclinic, P21/c with a = 5.8138(2), b = 27.3496(8), c = 7.5663(2) A° , β = 103.059(3)◦, and Z = 4). The vanadium(V) cation is in a pentagonal bipyramidal environment axially coordinated to the oxo group and equatorially to two hydroxylamido groups in a side-on fashion. The fifth equatorial binding site and the other apical position are occupied by an N and an O atom, respectively, from the methioninate anion acting as a bidentate ligand.

Abstract

The crystal structure of pyridinium 6-methyl-1,2,3,-oxathiazine-4(3H)-one-2,2-dioxide [(C5NH6)(C4H4NO4S)], for short, pyH(ace), was determined by X-ray diffraction methods. It crystallizes as a twin in the monoclinic space group P21/c with a=6.9878(9), b=7.2211(7), c=21.740(2) Å, β=91.67(1)° and Z=4 molecules per unit cell. The structure was determined employing 1599 reflections with I>2 σ(I) from one of the twin domains and refined employing 2092 reflections from both crystal domains to an agreement R1 factor of 0.0466. Besides electrostatic attractions, intermolecular pyH···O=C(ace) hydrogen bonds stabilize the acesulfamate anion and the pyridinium cation into planar discrete units parallel to the (100) crystal plane. The units form stacks of alternating ace and pyH+ ions along the a axis that favors inter-ring π–π interactions. The Fourier transform-infrared (FT-IR) spectrum of the compound was recorded and is briefly discussed. Some comparisons with related pyridinium saccharinate salts are also made.

Ammonium acesulfamate, (NH4)C4H4NO4S, was prepared by the reaction of acesulfamic acid and ammonium carbonate in aqueous solution, and characterized by elemental analysis and 1H and 13C NMR spectroscopy. Its crystal and molecular structure was determined by single-crystal X-ray diffraction methods. The substance crystallizes in the orthorhombic space group Pnma with Z = 4 molecules per unit cell. The NH4+ ion generates medium to strong hydrogen bonds with the carbonylic oxygen, the iminic nitrogen and the sulfonyl oxygen atoms of the acesulfamate anion. The FTIR spectrum of the compound was also recorded and is briefly discussed.

Abstract

Magnesium acesulfamate, Mg(C4H4NO4S)2·6H2O, was prepared by the reaction of acesulfamic acid and magnesium carbonate in aqueous solution, and characterized by elemental analysis. Its crystal structure was determined by single crystal X-ray diffraction methods. The substance crystallizes in the triclinic space group P1̅ with one molecule per unit cell. The FTIR spectrum of the compound was also recorded and is briefly discussed. Some comparisons with other simple acesulfamate and saccharinate salts are also made.

Abstract

The title compound was prepared by reaction, in aqueous solution, of Tl2CO3 and H2C2O4·2H2O in a molar ratio of 1:2. Its crystal structure was solved by X-ray diffraction methods. It crystallizes in the monoclinic space group P21/a with Z = 2 molecules per unit cell. The oxalic acid molecule and the oxalate anion are planar, residing on crystallographic inversion centers, and linked to each other by strong O–H···O hydrogen bonds giving rise to a polymeric structure. The Tl(I) ion is in a distorted polyhedral coordination with nine neighboring O atoms, five of oxalate anions and four others of oxalic acid molecules. The FTIR and FT-Raman spectra of the compound were also recorded and are briefly discussed.