ABSTRACT The synthesis of the title compound, C14H19BrN2OS, involves the reaction of 4-bromobenzoyl chloride with potassium thiocyanate in acetone followed by condensation of the resulting 4-bromobenzoyl isothiocyanate with di-n-propylamine. Typical thiourea carbonyl and thiocarbonyl double bonds, as well as shortened C—N bonds, are observed in the title compound. The short C—N bond lengths in the centre of the molecule reveal the effects of resonance in this part of the molecule. The asymmetric unit of the title compound contains two crystallographically independent molecules, A and B. There is very little difference between the bond lengths and angles of these molecules. In molecule B, one di-n-propyl group is twisted in a −antiperiplanar conformation with C—C—C—H = −179.1 (3)° and the other adopts a −synclinal conformation with C—C—C—H = −56.7 (4)°; in molecule A the two di-n-propyl groups are twisted in + and −antiperiplanar conformations, with C—C—C—H = −179.9 (3) and 178.2 (3)°, respectively. In the crystal, the molecules are linked into dimeric pairs via pairs of N—H...S hydrogen bonds.
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ABSTRACT: N-(R-carbamothioyl)cyclohexanecarboxamides (R: diethyl, di-n-propyl, di-n-butyl, diphenyl and morpholine-4) and their Ni(II) and Cu(II) complexes have been synthesized and characterized by elemental analyses, FT-IR and NMR methods. N-(diethylcarbamothioyl)cyclohexanecarboxamide, HL1, C12H22N2OS, crystallizes in the orthorhombic space group P212121, with Z = 4, and unit cell parameters, a = 6.6925(13) Å, b = 9.0457(18) Å, c = 22.728(5) Å. The conformation of the HL1 molecule with respect to the thiocarbonyl and carbonyl moieties is twisted, as reflected by the torsion angles O1–C6–N2–C5, C6–N2–C5–N1 and S1–C5–N2–C6 of 1.68°, −67.47° and 115.50°, respectively. The structure of HL1 also shows a delocalization of the π electrons of the thiocarbonyl group over the C–N bonds. The ring puckering analysis shows that the cyclohexane ring has a chair conformation. The bis(N-(morpholine-4-carbonothioyl)cyclohexane carboxamido)nickel(II) complex, Ni(L5)2, C24H38N4NiO4S2, crystallizes in the monoclinic space group P21/c, with Z = 4, and unit cell parameters, a = 16.919(3) Å, b = 8.3659(17) Å, c = 19.654(4) Å, β = 107.43(3)°. Ni(L5)2 is a cis-complex with a slightly distorted square-planar coordination of the central nickel by two oxygen and two sulfur atoms.Journal of Coordination Chemistry. 01/2009; 62(2):266-276.
Article: A short history of SHELX.[show abstract] [hide abstract]
ABSTRACT: An account is given of the development of the SHELX system of computer programs from SHELX-76 to the present day. In addition to identifying useful innovations that have come into general use through their implementation in SHELX, a critical analysis is presented of the less-successful features, missed opportunities and desirable improvements for future releases of the software. An attempt is made to understand how a program originally designed for photographic intensity data, punched cards and computers over 10000 times slower than an average modern personal computer has managed to survive for so long. SHELXL is the most widely used program for small-molecule refinement and SHELXS and SHELXD are often employed for structure solution despite the availability of objectively superior programs. SHELXL also finds a niche for the refinement of macromolecules against high-resolution or twinned data; SHELXPRO acts as an interface for macromolecular applications. SHELXC, SHELXD and SHELXE are proving useful for the experimental phasing of macromolecules, especially because they are fast and robust and so are often employed in pipelines for high-throughput phasing. This paper could serve as a general literature citation when one or more of the open-source SHELX programs (and the Bruker AXS version SHELXTL) are employed in the course of a crystal-structure determination.Acta Crystallographica Section A Foundations of Crystallography 02/2008; 64(Pt 1):112-22. · 2.24 Impact Factor
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ABSTRACT: 2-Chloro-N-(diethylcarbamothioyl)benzamide (C(12)H(15)ClN(2)OS) has been synthesized and characterized by elemental analysis and IR spectroscopy. The crystal and molecular structure of the title compound has been determined from single crystal X-ray diffraction data. It crystallizes in the orthorhombic space group Pbca, Z=8 with a=9.581(3)A, b=9.992(3)A, c=26.640(8)A, V=2550.5(13)A(3) and D(calc)=1.410 Mg/m(3). The molecular geometry and vibrational frequencies of 2-chloro-N-(diethylcarbamothioyl)benzamide in the ground state have been calculated using the Hartree-Fock and density functional using Becke's three-parameter hybrid method with the Lee, Yang and Parr correlation functional (B3LYP) methods with 3-21G and 6-31G(d) basis sets. The calculated geometric parameters were compared to the corresponding X-ray structure of the title compound. The raw B3LYP frequencies approximate the experimental data much better than the results of Hartree-Fock. The scaled B3LYP/6-31G(d) results were more reliable than those obtained using the B3LYP/3-21G method with the mean absolute deviation about 13.7 cm(-1). On the basis of the comparison between calculated and experimental results, assignments of fundamental vibrational modes were examined.Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy 01/2008; 68(5):1347-55. · 1.98 Impact Factor