The Molecular Conformation of 1e,2a,6e-Trimethyl-4e-phenyl-4a-acetoxypiperidine Hydrobomide in the Crystalline State

1973 ◽  
Vol 51 (10) ◽  
pp. 1535-1542 ◽  
Author(s):  
K. Hayakawa ◽  
M. N. G. James
Keyword(s):  
Molecular Conformation ◽  
Heavy Atom ◽  
Chair Conformation ◽  
Piperidine Ring ◽  
Monoclinic Space Group ◽  
Narcotic Analgesics ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
Heavy Atom Method ◽  
The Ideal

The title compound represents one analog of the synthetic 4-phenylpiperidine narcotic analgesics. The crystal structure was determined by the heavy-atom method from data collected on an automated diffractometer. The crystals are monoclinic, space group P21/c, with unit cell dimensions a = 11.833 Å, b = 11.551 Å, c = 14.659 Å and β = 121° 9′. The final residual, R, was 0.056. The stereochemistry of the substituents on the piperidine ring as deduced by this structural determination (1e,2a,6e-trimethyl-4e-phenyl-4a-acetoxypiperidine) confirms the p.m.r. results on the alcohol precursor as trans 2-Me/6-Me and trans 2-Me/4-Ph. There is a normal length N—H … Br hydrogen bond of 3.234 Å; most intramolecular bond lengths and angles are within the expected ranges but some distortion of the ideal chair conformation of the piperidine ring occurs.

Crystal structure of diethylammonium tetrachloro(p-phenoxyphenyl)tellurate

1984 ◽  
Vol 62 (1) ◽  
pp. 32-35 ◽  
Author(s):  
Raj K. Chadha ◽  
John E. Drake ◽  
Masood A. Khan
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Heavy Atom ◽  
Unit Cell ◽  
Monoclinic Space Group ◽  
Secondary Interaction ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
Heavy Atom Method ◽  
Interionic Hydrogen

The crystal structure of diethylammonium tetrachloro(p-phenoxyphenyl)tellurate has been determined by the heavy atom method. The crystals are monoclinic, space group C2/c, with unit cell dimensions a = 19.675(5), b = 7.634(3), c = 28.716(6) Å, β = 105.58(2)°, and Z = 8. For 2636 "observed" reflections (I > 3σ(I)), R = 0.030. The primary geometry about tellurium is based on a square pyramid with a secondary interaction on the vacant side of the tellurium coordination octahedron. The ions are apparently linked by weak interionic hydrogen bonding along the crystallographic b axis.

Crystal and Molecular Structure of the Synthetic Intermediate, 2-Bromo-3-methoxy-5-hydroxy-5,6,7,8,9,10,13,14-octahydro-8-methyl-10,13-N-acetylaminomethano-phenanthrene, C19H24O3NBr

1973 ◽  
Vol 51 (16) ◽  
pp. 2637-2638 ◽  
Author(s):  
H. Lynton ◽  
P. Y. Siew
Keyword(s):  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Monoclinic Space Group ◽  
Asymmetric Unit ◽  
Full Matrix ◽  
Cell Dimensions ◽  
Ring Nitrogen ◽  
Unit Cell Dimensions ◽  
Synthetic Intermediate ◽  
Heavy Atom Method

Crystals of the synthetic intermediate, 2-bromo-3-methoxy-5-hydroxy-5,6,7,8,9,10,13,14-octahydro-8-methyl-10,13-N-acetyl aminomethano-phenanthrene, C19H24O3NBr, are monoclinic, space group P21/n, unit cell dimensions a = 10.62(1), b = 14.47(2), c = 23.88(2) Å, β = 99.4(2)°, z = 8 with two molecules in the asymmetric unit. The structure was solved by the heavy atom method and refined by full matrix least squares to R = 0.096 for 2120 observed reflections. The conformation was found to be cis at the junction between rings A and B making further cyclization to obtain an A ring nitrogen bridge not possible.

The crystal structure of 4,7-oxido-7-methyl-7-hydroxymethyl-2,2,6,6-tetramethylpiperidin-1-oxyl

1982 ◽  
Vol 60 (18) ◽  
pp. 2392-2397 ◽  
Author(s):  
M. Cygler
Keyword(s):  
Direct Methods ◽  
Chair Conformation ◽  
Hydroxyl Group ◽  
Piperidine Ring ◽  
Monoclinic Space Group ◽  
Intensity Data ◽  
Asymmetric Unit ◽  
Torsion Angles ◽  
Cell Dimensions ◽  
Unit Cell Dimensions

4,7-Oxido-7-methyl-7-hydroxymethyl-2,2,6,6-tetramethylpiperidin-1-oxyl, C12H22NO3, crystallizes in the monoclinic space group P21/m with unit cell dimensions a = 8.041(1), b = 13.348(1), c = 5.945(1) Å, β = 95.90(1)°, Z = 2. Intensity data were measured on a diffractometer and the structure solved by direct methods. The least-squares refinement converged at R = 0.039 for 1304 reflections. Two enantiomeric molecules, differing in the position of the OH group, occupy the same site in the asymmetric unit (each with a probability of 0.5) giving rise to a disorder of the hydroxyl group. The piperidine ring adopts the usual chair conformation, with C—C—C—C torsion angles being intermediate between those observed for C(4) mono- and for bisubstituted nitroxypiperidine derivatives. The N—O bond is 1.282(2) Å long, and it makes an angle of 18.5(2)° with the CNC plane. Molecules are connected by O—H … O hydrogen bonds. The influence of the degree of substitution at C(4) on ring geometry is discussed.

scholarly journals The crystal and molecular structure of the bis(N,N,N′,N′-tetramethylethanediamine) adduct of I(Br)InInBr2, In2Br3I•2C6H16N2, an indium–indium bonded molecule

1984 ◽  
Vol 62 (3) ◽  
pp. 601-605 ◽  
Author(s):  
Masood A. Khan ◽  
Clovis Peppe ◽  
Dennis G. Tuck
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Orthorhombic Space Group ◽  
Trigonal Bipyramidal ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
Heavy Atom Method ◽  
Distorted Trigonal Bipyramidal

The crystal structure of the title compound has been determined by the heavy atom method. The crystals are orthorhombic, space group Pbca, with unit cell dimensions a = 22.795(3) Å, b = 17.518(2) Å, c = 12.396(3) Å, Z = 8; R = 0.0409 for 1527 unique "observed" reflections. The structure is disordered, with each halogen site (X) occupied by 75% Br, 25% I. The molecule consists of two X2(tmen)In units (tmen = N,N,N′,N′-tetramethylethanediamine) with distorted trigonal bipyramidal geometry, joined by an In—In bond 2.775(2) Å in length.

Conformation of azaphosphorinane ring. Crystal structures of 2,2,6,6-tetramethyl-4,4-diphenyl-1,4-azaphosphorinanium perchlorate and 2,2,6,6-tetramethyl-4-oxo-4-phenyl-1,4-azaphosphorinan-1-oxyl (stable nitroxy radical)

1983 ◽  
Vol 61 (3) ◽  
pp. 427-433 ◽  
Author(s):  
Miroslaw Cygler ◽  
Janusz Skolimowski
Keyword(s):  
Crystal Structures ◽  
Heavy Atom ◽  
Phenyl Group ◽  
Direct Methods ◽  
Chair Conformation ◽  
Monoclinic Space Group ◽  
Compound I ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
Unit Cell Dimensions

Crystal structures of 2,2,6,6-tetramethyl-4,4-diphenyl-1,4-azaphosphorinanium perchlorate (I) and 2,2,6,6-tetramethyl-4-oxo-4-phenyl-1,4-azaphosphorinan-1-oxyl (II) were determined. Compound I crystallizes in the monoclinic space group C2/c with unit cell dimensions a = 18.2967(7), b = 10.9413(6), c = 20.8714(13) Å, β = 90.79(1)° (at 115 K), and II crystallizes in the orthorhombic space group Pn21a with a = 8.076(1), b = 10.139(1), c = 17.894(1) Å. Intensity data were measured on a diffractometer at 115 K for I and at the room temperature for II. The structures were solved by a combination of heavy-atom and direct methods and refined to R = 0.036 (3968 reflections) for I and 0.039 (1451 reflections) for II.The azaphosphorinane ring adopts a chair conformation in both molecules, being flattened in the P part in I and in the N part in II. In molecule I the equatorial phenyl group is nearly parallel to the approximate plane of symmetry of the molecule, and the axial phenyl group is perpendicular to that plane. In molecule II the P=O bond is axial and the phenyl group is equatorial. The CN(O)C group is not planar. The N—O bond makes an angle of 18.0(3)° with the CNC plane. The CNC angle of 129.3(3)° is larger than that found in nitroxypiperidine analogues.

Studies on tellurium-carbon bonded compounds. II. The crystal structure of [Heptane-3,5-dionato(2 - )]tellurium(II) ('1,1′-Dimethylacetylacetone tellurium(II)')

1977 ◽  
Vol 30 (3) ◽  
pp. 487 ◽  
Author(s):  
JC Dewan ◽  
J Silver
Keyword(s):  
Crystal Structure ◽  
Least Squares ◽  
Title Compound ◽  
Heavy Atom ◽  
Chair Conformation ◽  
Heterocyclic Ring ◽  
Monoclinic Space Group ◽  
Hydrogen Atoms ◽  
Full Matrix ◽  
Heavy Atom Method

The structure of the title compound has been determined by the heavy- atom method from 973 reflections, measured with a diffractometer, and refined by full-matrix least-squares methods to R 0.030. Crystals are monoclinic, space group P21, a = 8.69(1), b = 4.86(1), c = 10.14(2) Ǻ, β = 98.7(1)�, Z = 2. In the discrete molecules of the complex a tellurium(II) atom is bonded to one bivalent heptane-3,5-dione ligand through the α-carbon atoms [Te-C 2.184(6), 2.206(7) Ǻ; C-Te-C 89.7(3)�], forming a heterocyclic ring of chair conformation with the methyl substituents both in equatorial positions. The molecules are arranged in a zig-zag polymeric manner about the 21 axes at x = 0 and z = 0. All hydrogen atoms have been located.

Crystal and molecular structure of the m-bromobenzoate derivative of bisnorquassin

1970 ◽  
Vol 48 (2) ◽  
pp. 307-311 ◽  
Author(s):  
H. Lynton
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Unit Cell ◽  
Anisotropic Temperature ◽  
Cell Dimensions ◽  
Final Agreement ◽  
Unit Cell Dimensions ◽  
Heavy Atom Method ◽  
Atomic Parameters

The molecular structure of the m-bromobenzoate derivative of bisnorquassin, C27H27O7Br, has been determined by the heavy atom method. The compound crystallizes in the orthorhombic system, space group P212121, with unit cell dimensions a = 20.09 ± 0.02 Å, b = 14.63 ± 0.02 Å, c = 8.06 + 0.01 Å and 4 molecules in the unit cell. Final atomic parameters have been obtained from a blockdiagonal least-squares refinement using anisotropic temperature parameters. The final agreement residual for 1665 observed reflections is R = 0.107.The structure of bisnorquassin previously proposed by Findlay and Cropp, on the basis of spectroscopic and chemical evidence, is shown to be essentially correct.

Penberthycroftite, [Al6(AsO4)3(OH)9(H2O)5]·8H2O, a second new hydrated aluminium arsenate mineral from the Penberthy Croft mine, St. Hilary, Cornwall, UK

2016 ◽  
Vol 80 (7) ◽  
pp. 1149-1160 ◽  
Author(s):  
I. E. Grey ◽  
J. Betterton ◽  
A. R. Kampf ◽  
C. M. Macrae ◽  
F. L. Shanks ◽  
...  
Keyword(s):  
Layer Structure ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Single Crystal Diffraction ◽  
Calculated Density ◽  
Metal Atoms ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
Hydrated Aluminium ◽  
The Ideal

AbstractPenberthycroftite, ideally [Al6(AsO4)3(OH)9(H2O)5]·8H2O, is a new secondary aluminium arsenate mineral from the Penberthy Croft mine, St. Hilary, Cornwall, England, UK. It occurs as tufts of white, ultrathin (sub-micrometre) rectangular laths, with lateral dimensions generally < 20 μm. The laths are flattened on {010} and elongated on [100]. The mineral is associated with arsenopyrite, bettertonite, bulachite, cassiterite, chalcopyrite, chamosite, goethite, liskeardite, pharmacoalumite–pharmacosiderite and quartz. Penberthycroftite is translucent with a white streak and a vitreous to pearly lustre. The calculated density is 2.18 g/cm3. Optically, only the lower and upper refractive indices could be measured, 1.520(1) and 1.532(1) respectively. No pleochroism was observed. Electron microprobe analyses (average of 14) with H2O obtained from thermogravimetric analysis and analyses normalized to 100% gave Al2O3 = 31.3, Fe2O3 = 0.35, As2O5 = 34.1, SO3 = 2.15 and H2O = 32.1. The empirical formula, based on nine metal atoms and 26 framework anions is [Al5.96Fe0.04(As0.97Al0.03O4)3(SO4)0.26(OH)8.30(H2O)5.44](H2O)7.8, corresponding to the ideal formula [Al6(AsO4)3(OH)9(H2O)5]·8H2O. Penberthycroftite is monoclinic, space group P21/c with unit-cell dimensions (100 K): a = 7.753(2) Å, b = 24.679(5) Å, c = 15.679(3) Å and β = 94.19(3)°. The strongest lines in the powder X-ray diffraction pattern are [dobs in Å(I) (hkl)] 13.264(46) (011); 12.402(16)(020); 9.732(100)(021); 7.420(28)(110); 5.670(8)(130); 5.423(6)(1̄31). The structure of penberthycroftite was solved using synchrotron single-crystal diffraction data and refined to wRobs = 0.059 for 1639 observed (I> 3σ(I)) reflections. Penberthycroftite has a heteropolyhedral layer structure, with the layers parallel to {010}. The layers are strongly undulating and their stacking produces large channels along [100] that are filled with water molecules. The layers are identical to those in bettertonite, but they are displaced relative to one another along [001] and [010] such that the interlayer volume is decreased markedly (by ∼10%)relative to that in bettertonite, with a corresponding reduction in the interlayer water content from 11 H2O per formula unit (pfu) in bettertonite to 8 H2O pfu in penberthycroftite.

scholarly journals Crystal and Molecular Structure of the 1:1 Complex of Chloral Hydrate and 7-Bromo-2,3-dihydro-1-methyl-5-phenyl-1,4-benzodiazepin-2-one

1971 ◽  
Vol 49 (20) ◽  
pp. 3401-3404 ◽  
Author(s):  
R. F. Dunphy ◽  
H. Lynton
Keyword(s):  
Chloral Hydrate ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Unit Cell ◽  
Orthorhombic System ◽  
Cell Dimensions ◽  
Final Agreement ◽  
Unit Cell Dimensions ◽  
Heavy Atom Method ◽  
Atomic Parameters

The structure of a 1:1 complex of chloral hydrate and 7-bromo-2,3-dihydro-1-methyl-5-phenyl-1,4-benzodiazepin-2-one has been determined by the heavy atom method. The complex crystallizes in the orthorhombic system, space group Pbca, with unit cell dimensions a = 13.45(1), b = 26.74(2), c = 11.23(1) Å and 8 molecules in the unit cell. The 1:1 complex of chloral hydrate and diazepam, 7-chloro-2,3-dihydro-1-methyl-5-phenyl-1,4-benzodiazepin-2-one, is isomorphous with the above compound and has unit cell dimensions a = 13.43(1), b = 26.60(2), c = 11.20(1) Å. The final atomic parameters have been obtained from a block-diagonal least squares refinement using anisotropic thermal parameters. The final agreement residual for 575 observed reflections is R = 0.079.The structure consists of chains of chloral hydrate and Br-diazepam molecules linked by hydrogen bonds.

Crystal structure analysis of ebastine [4-(4-benzhydryloxy-1-piperidyl)-1-(4-tert-butylphenyl) butan-1-one]: an oral histamine antagonist

2015 ◽  
Vol 48 (4) ◽  
pp. 1299-1301 ◽  
Author(s):  
Ranjana Sharma ◽  
Dixit Prasher ◽  
R. K. Tiwari
Keyword(s):  
Bond Length ◽  
Chair Conformation ◽  
Crystal Structure Analysis ◽  
Piperidine Ring ◽  
X Ray Diffraction ◽  
H1 Receptor ◽  
Calculated Density ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
Good Agreement

Ebastine belongs to the category of second-generation non-sedating H1 receptor antagonists and is chiefly used for the treatment of allergic rhinitis and chronic urticaria. The present paper reports findings on the crystal and molecular structure of ebastine, employing the technique of single-crystal X-ray diffraction. Ebastine crystallizes in the monoclinicP21/cspace group with unit-cell dimensionsa= 16.5890 (12),b= 10.9575 (8),c= 16.6795 (11) Å, β = 113.623 (2)°,V= 2777.8 (3) Å3,Z= 4 and calculated density amounting to 1.123 Mg m−3. The structure factor value was observed 1016 and finalR= 0.0496 for 4360 unique reflections. The piperidine ring in the ebastine molecule was found to exist in a chair conformation, and the C—N bond length was 1.459 (3) Å, thereby showing good agreement with the standard C—N bond length of 1.472 Å.

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