Synthesis, characterization, peripheral studies, and structural analysis of E-4-(N-methylanilino)-3-pentene-2-one, C12H15NO

Crystallographic structural refinement of E-4-(N-methylanilino)-3-pentene-2-one (I) has been carried out by means of three-dimensional single-crystal X-ray diffractometry. The title compound crystallizes in space group C2 (No. 5,Z = 4). The lattice constants are a = 21.543(4), b = 6.433(1), c = 8.019(2) Å, and = 97.82(3)°. Characterizations include physical property determinations and spectrometric identifications employing IR, ¹H and ¹³C NMR, and X-ray powder analyses. The molecules in the crystal lattice are held together by van der Waals forces. Selected bond distances and angles are presented and discussed as well as synthesis and peripheral studies.     

X-ray structures of two methoxybenzo[b]thiophenes

The crystal and molecular structures of two methoxybenzo[b]thiophenes have been determined by three-dimensional, single-crystal X-ray diffractometry. Both 3-(4-hydroxy-3, 5-dimethoxybenzoyl)-2-(4-methoxyphenyl)-6-methoxybenzo[b]thiophene and 3-(2,6-dimethoxybenzoyl)-2-(4-methoxyphenyl)-6-methoxybenzo[b]thiophene (hereafter referred to asI andII, respectively) crystallize in the monoclinic centrosymmetric space groupP2₁/n (No. 14, C _2h ⁵ ) with four formula units-per cell witha=6.866(1),b=28.638(2),c=11.830(2) Å, and =105.52(1)° anda=9.328(1),b=7.977(1),c=29.650(4) Å, and =97.87(1)°, respectively. The phase problems were solved by direct methods and the respective final full-matrix least-squares refinements converged toR=0.046 and 0.031. The structures differ in the positioning of the dimethoxy groups of the benzoyl ligands and the addition of a hydroxyl group inI. The molecules in the crystal lattice are held together by van der Waals forces plus the addition of hydrogen bonding in compoundI. Selected bond distances and angles and torsion angles are tabularized.     

X-ray crystal structure ofcis-H(Ph3Si)Pt[Ph2P(CH2)4PPh2] ·0.5 C6H6

The title compound, cis-hydrido(triphenylsilyl)-1,4-butanediyl-bis-(diphenylphosphine)platinum(II) (I), crystallizes in the monoclinic space groupP2 ₁/n (No. 14) witha=9.472(4),b=16.924(5),c=25.799(4) Å, β=91.29(3)° andZ=4. The structure was solved using the direct methods and refined by the full-matrix least-squares procedure to yield residuals ofR=0.024 andR _w =0.025 based on 4160 unique reflections. The square-planar geometry about the Pt atom is angularly distorted with P(1)?Pt?P(2) and Si?Pt?P(2) angles of 103.5(1) and 102.1(1)°, respectively. The Pt?P(1) bond is longer than the Pt?P(2) bond due to thetrans influence of the SiPh₃ group. Distortion due to steric bulk of the ligands is accommodated by the opening of the tetrahedral angles at the silicon and phosphorous atoms.     

Syntheses, characterization, and structural analyses of several f-block isothiocyanatonitrato complexes

Reactions of tetra-n-butylammonium thiocyanate with lanthanide and uranyl nitrates yield complexes of the general type [(Bu)₄N]_x[M(NCS)_y(NO₃)_z]. Samples of [(Bu)₄N]₂ [UO₂(NCS)₃( NO₃)] (1), [(Bu)₄N]₃[Yb(NCS)₄(NO₃)₂] (2), and [(Bu)₄N]₃[Nd(NCS)₄(NO₃)₂rsqb; (3) were prepared from alcohol solutions. Crystallization of 1 occurs in the centrosymmetric monoclinic space group C2/c (No. 15) with a = 17.949(4) Å, b = 16.587(3) Å, c = 16.763(3) Å; = 99.77(3)°; and Z = 4. The seven-coordinate uranium(VI) ion exhibits a pentagonal bipyramid coordination environment. Crystallization of 2 occurs in the centrosymmetric orthorhombic space group Pnnn (No. 48) with a = 12.530(2) Å, b = 12.9440(10) Å, c = 21.203(2) Å; Z = 2. The eight-coordinate ytterbium(III) ion expresses a dodecahedral coordination environment. Crystallization of 3 occurs in the noncentrosymmetric monoclinic space group Cc (No. 9) with a = 16.556(2) Å, b = 18.130(2) Å, c = 23.984(4) Å; Z = 4. The 10-coordinate neodymium(III) ion exhibits a dodecahedral coordination environment. Characterization includes physical property determinations, conoscopic studies, IR spectroscopic identifications, and UV spectral data. Details of the syntheses along with selected bond distances and angles are presented and discussed.Deceased, 30 March 1999