The Crystal and Molecular Structure of 1α,2α-Methylene Gibberellin A3 Methyl Ester

The three-dimensional structure of the 1α,2α-methylene gibberellin A₃ methyl ester has been determined by single-crystal X-ray diffraction techniques. The crystals are monoclinic, space group P 2₁ with two molecules in the unit cell of dimensions a = 9.236, b = 7.109, c = 14.155 Å and β = 104.61º. The structure was refined to an R-value of 0.0983 for 1359 observed reflections.     

X-ray crystal structures of new chiral enaminones from 2,4-pentanedione and their heterocyclic derivatives

New chiral enaminones from 2,4-pentanedione (1, 4) and their 1,4-oxazepinium and 1,4-thiazepinium derivatives (5–7) were synthesized and their crystal structures were determined by single crystal X-ray diffraction studies. The crystallographic data for these compounds are as follows: (R)-(1-Methyl-3-oxo-but-1-enylamino)-phenylacetic acid methyl ester (1): a = 7.574(1) ?, b = 12.530(1) ?, c = 14.245(1) ?, P2₁2₁2₁. (R)-4-(2-hydroxy-1-phenyl-ethylamino)-pent-3-en-2-one (2): a = 5.543(1) ?, b = 9.433(1) ?, c = 12.237(2) ?, β = 100.687(3)°, P2₁. (2S, 3R)-3-hydroxy-2-(1-methyl-3-oxobut-1-enylamine) butyric acid methyl ester (3): a = 5.583(1) ?, b = 8.660(1) ?, c = 12.149(1) ?, α = 92.85(1)°, β = 91.00(1)°, γ = 90.16(1)°, P1. (R)-3-[2-Methoxycarbonyl-2-(1-methyl-3-oxo-butylideneamino)-ethyldisulfanyl]-2-(1-methyl-3-oxo-butylideneamino)-propionic acid methyl ester (4): a = 9.309(1) ?, b = 11.460(1) ?, c = 11.310(1) ?, β = 112.582(2)°,P2_1.(3R)-5,7-dimethyl-3-phenyl-2,3-dihydro-[1,4]oxazepinium trifluoroborate (5): a = 8.958(1) ?, c = 18.085(1) ?, P4₃. (2S, 3R)-3-methoxycarbonyl-2, 5,7-trimethyl-2, 3-dihydro-[1,4] oxazepin-4-ium trifluroborate (6): a = 8.626(1) ?, b = 11.597(1) ?, c = 13.733(19) ?, P2₁2₁2₁. 3-Methoxycarbonyl-5, 7-dimethyl-2, 3-dihydro- [1,4]-thiazepin-4-ium trifluoroborate (7): a = 13.737(1) ?, b = 6.244(1) ?, c = 16.041(1) ?, β = 104.927(2)°, P2₁/n.     

Studies on the conformation of α-arylcinnamic acids and their esters: Crystal structures of methyl (E)-2,3-bis(3,4-dimethoxyphenyl)propenoate and methyl (Z)-2,3-bis(3,4-dimethoxyphenyl)propenoate

The conformations of stereoisomers of -arylcinnamic acids and their esters are discussed based on crystal structures of the E and Z forms of 2,3-bis(3,4-dimethoxyphenyl)propenoic acid and its methyl ester. In the E forms of the cinnamic acid and the cinnamic acid ester, the plane of the -aryl substituent is approximately perpendicular to that of the rest of the molecule. In the Z forms the plane of the carboxyl or methoxycarbonyl group is approximately perpendicular to that of the ethylenic group, and both the aromatic group planes are significantly twisted out of the ethylenic group plane. Crystal structures of methyl (E)-2,3-bis(3,4-dimethoxyphenyl)propenoate (space group P2₁/n with a = 8.1697(5), b = 11.3882(9), c = 19.7766(9) Å, = 90.058(4)°, V = 1840.0(2) ų, and Z = 4), monoclinic methyl (Z)-2,3-bis(3,4-dimethoxyphenyl)propenoate (space group P2₁/n with a = 11.183(2), b = 5.640(2), c = 29.737(7) Å, = 99.19(2)°, V = 1851.4(9) ų, and Z = 4), and orthorhombic methyl (Z)-2,3-bis(3,4-dimethoxyphenyl)propenoate (space group P2₁2₁2₁ with a = 8.849(4), b = 24.288(9), c = 8.734(3) Å, V = 1877(1) ų, and Z = 4) are reported.     

The Crystal and Molecular Structure of a Gibberellin A3 Pyrazoline Ester

The three-dimensional structure of the gibberellin A₃ pyrazoline ester 1 has been established by X-ray analysis. The compound crystallizes from acetone/hexane in the orthorhombic space group P 2₁2₁2₁ with four molecules in the unit cell of dimensions a = 8.853, b = 9.642, c = 23.307 Å. The final R-value is 0.038 for 1957 reflections.     

Crystal structure of a dehydroabietate derivative

The crystal structure of methyl-16, nor-5-hydroxy-6,7,15-trioxo dehydroabietate has been determined from three-dimensional X-ray diffraction data. The compound crystallizes in the orthorhombic space group P2₁2₁2 with unit cell parameters a = 19.226(3) Å, b = 11.075(3) Å, c = 8.375(2) Å, Z = 4, V = 1783.3(7) ų, d₀ = 1.36 gcm⁻³. The gross structure was determined by direct methods which on refinement yielded a final value of R index as 0.038. Ring A is a chair, ring B an envelope whereas the ring C adopts a strictly planar conformation. The rings A and B are trans fused. The ester group at C4 is cis fused to methyl carbon C15 whereas another methyl carbon C18 and oxo O(15) of the isopropyl group at C13 are rotated to positions 0.107(3) Å and 0.179(2) Å out of the plane of ring C.     

Paramagnetic Resonance of Radicals in Decomposed Solid N-Methyl-N. 2,4,6 Tetranitroanililne (Tetryl)

Electron paramagnetic resonance studies of uv decomposed solid N methyl N, 2,4,6-tetranitoanililne (tetryl), C₆(NO₂)₃ H₂ (CH₃ NNO₂) measured dissolved in benzene show the presence of a six line spectrum which can be accounted for by an unpaired electron interacing equally with three hydrogen nuclei with an isotropic spliltting of 10 Gauss and one nitrogen nuclei also with a splitting of 10.0 G. Studies of the radical in powders and single crystals show the g and A tensor and axial with diagonal components A ₁₁ = 27.0 G., A ₁ = 4.0 G. and g ₁ = 2.007 and g ₁₁ = 2.003. The spectrum is shown to be a nitroxide radical of tetryl, C₆(NO₂)₃H₂ (CH₃NO). The radical is stable at room temperature trapped in the solid the lattice but in a solution of benzene loses the CH₃ forming another radical.     

An X-ray Crystallographic Study of the Related Triazenes, 1,4-Di[(<Emphasis Type="Italic">E</Emphasis>)-2-(2-nitrophenyl)-1-diazenyl]piperazine and Methyl 4-{(E)-2-(4-methylpiperazino)-1-diazenyl}benzoate

Abstract The crystal structures of methyl 4-{(E)-2-(4-methylpiperazino)-1-diazenyl}benzoate (2a) and 1,4-di[(E)-2-(2-nitrophenyl)-1-diazenyl]piperazine (3a) have been determined by single crystal X-ray diffraction analysis. The bis-triazene (3a) adopts an unusual pseudo-boat conformation in the piperazine ring, with a dihedral angle of 52.20(0.06)° between the two planes defined within the piperazine ring. The crystal structures of 2a and 3a are compared with the structure of the triazene (4) and the closely related bis-triazene (5). The piperazine ring of 2a adopts a typical chair conformation, whereas the piperazine ring of 3a adopts an unusual boat conformation. Crystal data: 2a C₁₃H₁₈N₄O₂, monoclinic, space group P2₁ /n, a = 13.849(3) ?, b = 6.577(1) ?, c = 14.904(3) ?, α = 90°, β = 96.098(3)°, γ = 90° and V = 1,349.8(4) ?³, for Z = 4. 3a C₁₆H₁₆N₈O₄, triclinic, space group P-1, a = 7.6066(6) ?, b = 8.3741(7) ?, c = 14.507(1) ?, α = 78.673(1)°, β = 81.877(1)°, γ = 73.445(1)° and V = 865.0(1) ?³, for Z = 2. Index abstract The crystal structures of methyl 4-{(E)-2-(4-methylpiperazino)-1-diazenyl}benzoate (2a) and 1,4-di[(E)-2-(2-nitrophenyl)-1-diazenyl]piperazine (3a) have been determined by single crystal X-ray diffraction analysis.     

Synthesis and X-ray diffraction study of [UO<Subscript>2</Subscript>(NO<Subscript>3</Subscript>)<Subscript>2</Subscript>(H<Subscript>2</Subscript>O)<Subscript>2</Subscript>] · 2C<Subscript>12</Subscript>H<Subscript>18</Subscript>O

The compound [UO₂(NO₃)₂(H₂O)₂] · 2C₁₂H₁₈O was synthesized and studied by IR spectroscopy and X-ray diffraction. The structure consists of the neutral island groups [UO₂(NO₃)₂(H₂O)₂], which belong to the crystal-chemical group AB ⁰¹ ₂ M ¹ ₂ (A = UO₂ ²⁺, B ⁰¹ = NO₃⁻, M ¹ = H₂O) of uranyl complexes, and 1-adamantyl methyl ketone molecules. The characteristic features of the association of the complexes [UO₂(NO₃)₂(H₂O)₂] and 1-adamantyl methyl ketone molecules in the crystal structure via hydrogen bonds are considered with the use of Voronoi-Dirichlet polyhedra.     

Synthesis and Crystal Structure of 3-[(Naphthalen-2-yl)methyl]Isocoumarin

Abstract 3-[(Naphthalen-2-yl) methyl]isocoumarin was synthesized by the reaction of homophthalic acid with 2-(naphthalen-2-yl)acetyl chloride at elevated temperature and its crystal structure has been determined (C₂₀H₁₄O₂), Mr = 286.31, a = 13.704(3), b = 7.356(4), c = 7.042(7) ?, β = 99.21(3)°, space group Pc, Z = 2, and V = 700.7(8) ?³. The isocoumarin and the naphthalene ring systems are individually planar and the dihedral angle between the mean planes of these two ring systems is 70.05(8)°. Graphical Abstract Synthesis and crystal structure of 3-[(Naphthalen-2-yl)methyl]isocoumarin Aamer Saeed, Junmei Liang, Masood Parvez The synthesis and crystal structure of a novel isocoumarin, 3-[(naphthalen-2-yl)methyl]isocoumarin has been presented.      

Structural investigation of five N-arylsulfonyloxazolidines

The crystal structures of (1R,5R,8S)-8-[(2R,4R)-4-ethyl-3-(2,4,6- trimethyl-benzenesulfonyl)-oxazolidin-2-yl]-1-hydroxy-bicyclo[3.3.1]nonan-3-one (1), formic acid (1S,2R)-2-{2-[(2R,4R)-4-ethyl-3-(toluene-4-sulfonyl)-oxazolidin-2-yl]-cyclohexylidene}-1-trimethylsilanyl-ethyl ester (2), (2R,4R)-2-{(4S,5R,6S)-6-tertbutyl-2,2,4,5-tetramethyl-[1,3]dioxan-4-yl}-4-ethyl-3-(toluene-4-sulfonyl)-oxazolidine (3), (2S)-2-[(2R,4R,5R)-4-methyl-5-phenyl-3-(toluene-4-sulfonyl)-oxazolidin-2-yl]-3,4-dihydro-2H-naphthalen-1-one (4) and (1R)-1-[(2R,4R,5R)-4-methyl-5-phenyl-3-(toluene-4-sulfonyl)-oxazolidin-2-yl]-3,4-dihydro-1H-naphthalen-2-one (5) have been determined: (1) crystallizes in the orthorhombic space group P2₁2₁2₁ with cell dimensions a = 11.120(1), b = 13.809(1), c = 14.676(1) Å, (2) crystallizes in the monoclinic space group P2₁ with cell dimensions a = 12.577(3), b = 9.589(1), c = 13.971(3) Å, = 95.77(1) °, (3) crystallizes in the monoclinic space group P2₁ with cell dimensions a = 7.990(4), b = 11.282(9), c = 14.473(4) Å, = 96.31(3)°, (4) crystallizes in the orthorhombic space group P2₁2₁2₁ with cell dimensions a = 7.674(1), b = 14.647(1), c = 20.620(1) Å, (5) crystallizes in the monoclinic space group P2₁ with cell dimensions a = 7.890(2), b = 11.319(1), c = 13.493(3) Å, = 104.12(1)°.     

Synthesis and crystal structure of 1-(4-bromobenzyl)-4-methyl-2,6,7-trioxabicyclo[2.2.2]octane

1-(4-Bromobenzyl)-4-methyl-2,6,7-trioxabicyclo[2.2.2]octane, C₁₃H₁₅BrO₃, has been synthesized from 4-bromophenylacetic acid chloride via the oxetan ester (3-methyl-3-oxetanyl)methyl-2-(4-bromophenyl)acetate. The crystal structure of the title compound has been determined at low temperature (120 K), by X-ray diffraction methods. This compound crystallizes in the monoclinic space group P2₁/n (No. 14), Z = 4, with lattice parametersa = 6.019(5), b = 20.990(5), c = 9.915(2) Å, and = 101.29(1)°.     

Synthesis and molecular structure analysis of venlafaxine intermediate and its analog

1-(cyano-(4-methoxyphenyl) methyl cyclohexanol(2), C₂₄H₃₂N₂O₂, a Venlafaxine intermediate is found to crystallize in both monoclinic(2a) and orthorhombic(2b) crystal systems. The form2a crystallizes in the space groupC2/c with the cell parametersa = 23.506(3),b = 5.550(3),c = 23.192(3), and β = 115.116(2)^∘.2b crystallizes in space groupP2₁2₁2₁ with cell parametersa = 5.7850(6),b = 11.2680(6), andc = 20.6730(19). The intermolecular hydrogen bonding in the case of the monoclinic polymorph leads to the formation of dimer. The synthesis, characterization, and crystal structure studies of Venlafaxine analog 1-[2-1-(4-dimethylamino-phenyl)-ethylideneamino]-1-(4-methoxy-phenyl)-ethyl]-cyclohexanol(4) is reported.4 crystallizes inP―1 space group with cell parametersa = 10.801(7),b = 12.078(7),c = 9.928(5), α = 96.12(5)^∘, β = 110.49(5)^∘, and γ = 112.42(6)^∘.     

Hyperfine structure of EPR spectra of Cr5+ ions in irradiated sodium dichromate crystals

EPR spectra are studied of X-irradiated sodium dichromate crystals grown from an aqueous solution by evaporation at 31°C. Doublet lines of EPR-absorption are attributed to the Cr⁵⁺ ions in the CrO₄³⁻ and CrO₃⁻ radicals resulting from radiation decomposition of Cr₂O₇²⁻ and being in the lattice in two unequivalent positions. Hyperfine structure caused by interaction of an unpaired electron with Cr⁵³ nucleus were observed both at liquid nitrogen and room temperatures. For the line, caused by CrO₄³⁻ radical, g_y and A_y directions coincide and angles both between A_x, g_x and A_z, g_z make up ∼ 25°. The spectrum is described by usual spin Hamiltonian for S = 1/2 with following parameters (T = 77 K): for CrO: g_z = 1.984, g_y = 1.970, g_x = 1.961, |A_z| = 8.2 · 10⁻⁴ cm⁻¹, |A_y| = 13.7 × 10⁻⁴ cm⁻¹, |A_x| = 36.1 · 10⁻⁴ cm⁻¹; for CrO₃⁻: g_z = 1.915, g_y = 1.975, g_x = 1.985, |A_z| = 32.2 · 10⁻⁴ cm⁻¹.     

X-ray Crystal Structure of Grandiflorenic Acid [(−)-kaura-9(11)-16-dien-19-oic Acid] Methyl Ester,a Compound Formerly Considered as an Oily Derivative

Abstract  Grandiflorenic acid [(−)-kaura-9(11)-16-dien-19-oic acid] methyl ester (2), C₂₁H₃₀O₂, was synthesized from grandiflorenic acid, isolated from the plant Montanoa tomentosa. Compound (2) was formerly described as an oily derivative. X-ray diffraction analysis of (2) demonstrated that it consists of four rings, three six-membered rings (I, II and III) and one five-membered ring (IV). I, II and III rings occur in chair, twist, and envelope conformations, respectively. Ring IV occurs in a conformation between envelope and half-chair. The crystal of grandiflorenic acid methyl ester is in monoclinic crystal system with space group P2₁, lattice constants: a = 7.2170(10), b = 11.4170(10), c = 11.2850(10) ?, β = 98.700(10)°, V = 919.1(2) ?³ and Z = 2. Index Abstract  Grandiflorenic acid [(−)-kaura-9(11)-16-dien-19-oic acid] methyl ester (2) was synthesized. This compound was formerly considered as an oily derivative. The crystal structure of (2) was obtained by determination of X-ray diffraction from suitable single crystals.      

Structural Features of <Emphasis Type="Italic">Ortho</Emphasis>-hydroxy Bis-phenols and Their Comparison with <Emphasis Type="Italic">Para</Emphasis>-hydroxy Bis-phenols

Abstract The crystal structures of four bis-phenols are reported to substantiate the fact that the weak interactions play a major role in the crystal packing of bis-phenols. The reaction of 2,4-dimethylphenol with aldehydes such as 2-naphthaldehyde, terephthaldehyde in the presence of trifluoracetic acid gave 2-[bis(2-hydroxy 3,5-dimethylphenyl)methyl]naphthalene (1) and 4-[bis(2-hydroxy 3,5-dimethylphenyl) methyl]benzaldehyde (2), respectively. The 2-[bis-(2-hydroxy 3,5-dimethylphenyl)-methyl]naphthalene (1) crystallizes in orthorhombic, Pbca, a = 11.905(3) ?, b = 18.788(5) ?, c = 18.894(5) ?, 4-[bis(2-hydroxy 3,5-dimethylphenyl)methyl] benzaldehyde (2) in monoclinic, Cc, a = 8.880(3) ?, b = 16.394(7) ?, c = 13.700(5) ?, γ = 104.542(2)°. The reaction of 2-nitrobenzaldehyde with 2,4-dimethylphenol gave 2-benzo[c] isoxazo-3-yl 4,6-dimethylphenol (3) and its crystal parameters are orthorhombic, P2₁2₁2₁, a = 7.737(6) ?, b = 11.885(9) ?, c = 13.336(8) ?. The reaction of 2,6-dimethylphenol with 4-nitrobenzaldehyde and 2-chlorobenzaldehyde gave bis(4-hydroxy 3,5-dimethylphenyl)(4-nitrophenyl)methane (4) and bis(4-hydroxy 3,5-dimethylphenyl)(2-chlorophenyl)methane (5), respectively. The bis(4-hydroxy 3,5dimethylphenyl)(4-nitrophenyl)methane (4) crystallizes in monoclinic, C2/c, a = 25.921(1) ?, b = 12.202(4) ?, c = 15.6084(7) ?, β = 122.172(4)°, and bis(4-hydroxy 3,5-dimethylphenyl) (2-chlorophenyl)methane crystallizes as acetonitrile solvate (5) in triclinic, P-1, a = 12.314(3) ?, b = 14.111(3) ?, c = 15.078(5) ?, α = 98.268(2)°, β = 111.268(2)°, γ = 114.304(1)˚. The unit cell of 5 contains two pairs of crystallographically unsymmetric molecules of bis-phenols. Index abstract The crystal structures of four bis-phenols are reported to substantiate the fact that the weak interactions plays a major role in crystal packing and can induce symmetry non-equivalence among bis-phenols in unit cell of bis-phenols.      

Review: Different types of ordering

Homogeneous structures A_xB_y with identical A–A or B–B self‐coordination numbers T₁, T₂, T₃, of nearest, next‐nearest and third neighbors are selected. The maximum T_i values are 2 2 2 (1D row), 6 6 6 (2D hexagonal net) and 12 6 24 (3D cubic close‐packing). Reduced T₁ or T₂ values for A_xB_y can be related with attractive or repulsive A–A (or B–B) interactions. A single set of T₁ T₂ T₃; y/x values was obtained for y/x = 1–4 and 6. The y/x = 2 structures of three equivalent positions A, B and C are unfavourable for A = ⊕ and B = ⊖ charge or direction of magnetic moments. The spatial distribution of positive and negative potential near A⁺ and B⁻ positions gives rise to neutral C positions. Frustrated magnetic moments at C positions are disordered. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis of 7,4′-Bis-(hydroxyl)-8,3′,5′-tris-(hydroxymethyl)isoflavone and Crystal Structure of its Ester

Abstract 7,4′-bis-(hydroxyl)-8,3′,5′-tris-(hydroxymethyl)isoflavone (I) and its ester were synthesized and examined by IR, element analysis and ¹H NMR. The crystal of 7,4′-bis-(acetyl oxide)-8,3′,5′-tris-(acetoxymethyl)isoflavone (II) was studied by X-ray diffraction. (II) crystallizes in the monoclinic with space group P2 ₁ /c. a = 17.987(3) ?, b = 17.972(3) ?, c = 8.4087(11) ?, β = 97.703(3)°, V = 2693.7(6) ?³ and Z = 4. The molecular structure of the ester consists of a benzopyranone moiety, a phenyl moiety, two acetyl oxides and three acetoxymethyl groups. Hydrogen bonds and aromatic stacking interactions link the ester into a two-dimensional structure. Index Abstract 7,4′-bis-(hydroxyl)-8,3′,5′-tris-(hydroxymethyl)isoflavone and its ester were synthesized and examined by IR, element analysis and ¹H NMR. The result of the ester’s crystal structure showed that hydrogen bonding and aromatic π–π stacking assemble the ester into a two-dimensional networking structure.      

Pharmacologically Relevant Bifunctional Compounds Containing Chloroquinoline and Dihydropyrimidone Moieties: Syntheses and Crystal Structures of a Target Molecule and Selected Intermediates

Abstract  We report the regioselective synthesis and X-ray structure of the pharmacologically relevant 3-[2-(7-chloro-quinolin-4-ylamino)-ethylcarbamoyl]-4-(4-methoxy-phenyl)-1,6-dimethyl-2-oxo-1,2,3,4-tetrahydro-pyrimidine-5-carboxylic acid methyl ester (3) (triclinic, space group , a = 11.1775 (3), b = 13.6470 (4), c = 16.3680 (6) ?, α = 82.645 (1), β = 86.423 (1), γ = 88.415 (2)°, V = 2470.9 (1) ?³, Z = 4). Further support for the regioselectivity is provided by the X-ray structures of two intermediates, namely 4-(4-methoxy-phenyl)-1,6-dimethyl-2-oxo-1,2,3,4-tetrahydro-pyrimidine-5-carboxylic acid methyl ester, 8 (monoclinic, space group P2₁/c, a = 11.7710 (2), b = 5.5290 (1), c = 22.9500 (5) ?, β = 104.342 (1)°, V = 1447.08 (5) ?³, Z = 4), and 4-(4-methoxy-phenyl)-1,3,6-trimethyl-2-oxo-1,2,3,4-tetrahydro-pyrimidine-5-carboxylic acid methyl ester, 9 (monoclinic, space group P2₁/c, a = 16.6529 (7), b = 10.9426 (4), c = 8.2819 (3) ?, β = 91.395 (2)°, V = 1508.7 (1) ?³, Z = 4), which are also reported. The three compounds display significant differences in the conformations of their DHPM rings as well as a variety of hydrogen bonding arrangements in their crystals. Graphical Abstract  The synthetic strategy for deriving pharmacologically-relevant bifunctional compounds based on linked dihydropyrimidone and chloroquinoline moieties is reported, together with supporting X-ray structures of two synthetic intermediates and a representative target compound.      

Synthesis and Crystal Structure of 3-Quinuclidinyl α-(Cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate

Abstract The title compound 3-quinuclidinyl α-(cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate was obtained by the reaction of methyl α-(cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate with 3-quinuclidinol in n-heptane. Its structure was characterized by ¹H, ¹³C NMR, MS and X-ray single-crystal diffraction techniques: C₂₀H₂₅NO₃, M _r = 327.41, orthorhombic, space group P2₁2₁2₁ with a = 8.547(2), b = 11.428(4), c = 18.288(5) ?, V = 1786.3(9) ?³, Z = 4. The title compound comprises a tertiary α-hydroxy acid and a bicyclo[2.2.2]octan moiety. The crystal structure shows the presence of the intermolecular O(1)–H(1)···N(1) hydrogen bonds. Index Abstract The title compound, 3-quinuclidinyl α-(cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate was obtained by the reaction of methyl α-(cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate with 3-quinuclidinol in n-heptane and its crystal structure determined. The title compound comprises a tertiary α-hydroxy acid and a bicyclo[2.2.2]octan moiety. The crystal structure shows the presence of the intermolecular O(1)–H(1)···N(1) hydrogen bonds.      

Crystal and molecular structure of 2-bromo-5,6-dihydro-6-methyl-4H,8H-pyrido [3,2,1-de]phenanthridin-8-one

Crystals of the title compound, C₁₇H₁₄BrNO, are monoclinic, with space groupP2₁/a,a = 14.314(5),b = 15.009(11),c = 6.596(3) Å, and = 102.39(3) °. Diffraction data were collected with CuK radiation to a Bragg angle of 77 °. The structure was solved by the heavy-atom method and refined to anR index of 0.059 for 2129 reflections. In agreement with NMR results, the C=O group is orientedanti to the benzene ring, and the methyl group at C(6) is axial. Unlike 1-(p-bromobenzoyl)-2-methyl-1,2,3,4-tetrahydroquinoline, the heterocyclic ring assumes a well defined half-chair conformation. Except for C(5) and the methyl group at C(6), the whole molecule is very nearly planar.