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In the title compound, C12H14N22+·2Cl-, the 4,4'-dimethyl-2,2'-bipyridinium cation is essentially planar (r.m.s. deviation for all non-H atoms = 0.004 Å) and is located on a crystallographic inversion centre. The cations and chloride anions lie in planes parallel to (111) and are connected by N-H...Cl and C-H...Cl hydrogen bonds. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.003 Å; R factor = 0.036; wR factor = 0.080; data-to-parameter ratio = 14.7.
The title compound, C15H14N2O4, is an important intermediate for the synthesis of thermotropic liquid crystals. The dihedral angle between the two aromatic rings is 84.29 (4)°. An N-H...O hydrogen bond connects the molecules into chains running along the b axis. In addition, the crystal packing is stabilized by weak C-H...O hydrogen bonds. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.036; wR factor = 0.096; data-to-parameter ratio = 14.3.
The absolute configuration of the title compound, [Fe(C5H5)(C36H29OP2)], is Sp at the ferrocene group and S at the asymmetric C atom. Both P atoms have a trigonal-pyramidal conformation. There is a short intramolecular C-H...P contact with an H...P distance of 2.56 Å. The hydroxy group is involved in an intramolecular O-H...[pi]phenyl interaction. The crystal packing shows five very weak intermolecular C-H...[pi] contacts, with H...Cg distances between 3.26 and 3.39 Å (Cg is the centroid of a phenyl or cyclopentadienyl ring). Key indicators: single-crystal X-ray study; T = 162 K; mean σ(C–C) = 0.004 Å; R factor = 0.038; wR factor = 0.083; data-to-parameter ratio = 22.3.
The absolute configuration of the title molecule, [Fe(C5H5)(C38H34NP2)]·CHCl3, is R,Rp. The molecular structure is similar to the structure of the solvent-free compound [Fukuzawa, Yamamoto & Kikuchi (2007). J. Org. Chem. 72, 1514-1517], but some torsion angles about the P-Cphenyl bonds differ by up to 25°. The P atoms and the N atom have a distorted trigonal-pyramidal geometry. The chloroform solvate group donates a C-H...[pi] bond to the central benzene ring and is also involved in six intermolecular C-H...Cl contacts with H...Cl distances between 2.96 and 3.13 Å. Key indicators: single-crystal X-ray study; T = 163 K; mean σ(C–C) = 0.003 Å; R factor = 0.039; wR factor = 0.088; data-to-parameter ratio = 24.2.
The geometric parameters of the molecule of the title compound, C14H16O2P2, are in the usual ranges. It is a meso compound with the two chiral P atoms having opposite configurations. The P-CH2-CH2-P chain adopts a trans conformation [torsion angle -178.59 (17)°]. The P=O bonds are almost coplanar with the adjacent phenyl ring [torsion angles = 3.8 (3) and 0.3 (3)°]. Whereas one of them is synclinal [torsion angle = -59.0 (2)°] to the central C-C bond, the other is anticlinal [torsion angle = 56.6 (2)°] to the central C-C bond. The dihedral angle between the two phenyl rings is 5.2 (3)°. The molecules are linked by weak C-H...O hydrogen bonds. They crystallize in rows running along the c axis. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.005 Å; R factor = 0.038; wR factor = 0.093; data-to-parameter ratio = 15.2.
In the title compound, C27H20F6N2O2, the dihedral angles between the planes of the aromatic rings connected by the ether O atoms are 84.13 (8) and 75.06 (9)°. The crystal structure is stabilized by N-H...O and N-H...F hydrogen bonds. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.004 Å; R factor = 0.037; wR factor = 0.088; data-to-parameter ratio = 8.2.
In the title compound, C17H12F2N2OS, the planar thiazole ring (r.m.s. deviation = 0.012 Å) makes dihedral angles of 15.08 (9) and 81.81 (6)° with the 4-fluorophenyl and 2-fluorophenyl rings, respectively. The 2-fluorophenyl ring is disordered over two orientations with site-occupancy factors of 0.810 (3) and 0.190 (3). The structure contains intermolecular C-H...O hydrogen bonds. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.003 Å; disorder in main residue; R factor = 0.034; wR factor = 0.082; data-to-parameter ratio = 16.1.
The title compound, C16H14N4, features an aromatic ring with two 2,2´-dicyanopropyl residues in positions 1 and 3, which are located above and below the ring plane. The two residues differ in their conformation with respect to the aromatic ring: whereas one of the Cmethyl-C-Cmethylene-Caromatic torsion angles is gauche [68.93 (12)°], the other one is fully staggered [177.63 (9)°]. The crystal structure is stabilized by C-H...N hydrogen-bonding interactions. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.037; wR factor = 0.101; data-to-parameter ratio = 15.0.
4-Chloro-N-m-tolylbenzamide
(2009)
In the title compound, C14H12ClNO, the dihedral angle between the two aromatic rings is 11.29 (15)°. The crystal packing is stabilized by N-H...O hydrogen bonds linking the molecules into chains running along the c axis. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.004 Å; R factor = 0.066; wR factor = 0.178; data-to-parameter ratio = 13.7.
6-(4-Nitrophenoxy)hexanol
(2009)
The title compound, C12H17NO4, features an almost planar molecule (r.m.s. deviation for all non-H atoms = 0.070 Å). All methylene C-C bonds adopt an antiperiplanar conformation. In the crystal structure the molecules lie in planes parallel to (1\overline{1}2) and the packing is stabilized by O-H...O hydrogen bonds. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.003 Å; R factor = 0.066; wR factor = 0.185; data-to-parameter ratio = 13.2.
In the title molecule, C13H16ClNO, the mean plane of the atoms in the -CONH- group forms a dihedral angle of 42.0 (4)° with the benzene ring plane. In the crystal structure, molecules are linked by intermolecular N-H...O hydrogen bonds, generating C(4) chains along [100]. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.030; wR factor = 0.069; data-to-parameter ratio = 18.2.
The structure of the title compound, C14H9Cl3N2OS, is composed of discrete molecules with bond lengths and angles quite typical for thiourea compounds of this class. The plane containing the thiocarbonyl and carbonyl groups subtends dihedral angles of 48.19 (3) and 87.51 (3)° with the planes formed by the 3-chloro and 2,6-dichlorophenyl rings, respectively; the dihedral angle between the two benzene ring planes is 45.32 (3)°. An intramolecular N-H...O hydrogen bond stabilizes the molecular conformation and the molecules form intermolecular N-H...S and N-H...O hydrogen bonds, generating a sheet along the alpha axis. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.037; wR factor = 0.094; data-to-parameter ratio = 25.5.
The title compound, C14H6Cl6N2OS·0.5CHCl3, crystallizes with four 1-(2,6-dichlorobenzoyl)-3- (2,3,5,6-tetrachlorophenyl)thiourea molecules and two trichloromethane molecules in the asymmetric unit. The thiourea molecules exist in the solid state in their thione forms with typical thiourea C-S and C-O bonds lengths, as well as shortened C-N bonds. The -NH-C(=S)-NH-C(=O)- plane is almost perpendicular to the benzene ring in each thiourea molecule. Intramolecular N-H...O hydrogen bonds stabilize the molecular conformation and intermolecular N-H...S hydrogen bonds stabilize the packing arrangement. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.004 Å; R factor = 0.051; wR factor = 0.147; data-to-parameter ratio = 23.2.
The title molecule, C16H15ClN2OS, exists in the solid state in its thione form with typical thiourea C-S and C-O bonds lengths, as well as shortened C-N bonds. An intramolecular N-H...O hydrogen bond stabilizes the molecular conformation and intermolecular N-H...S hydrogen bonds link the molecules into centrosymmetric dimers. The dihedral angle between the aromatic rings is 50.18 (5)°. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.032; wR factor = 0.085; data-to-parameter ratio = 15.3.
The asymmetric unit of the title compound, C14H8Cl4N2OS·0.5H2O, contains two independent molecules with different conformations with respect to the aromatic ring planes, and one water molecule. The bond lengths and angles are typical of thiourea compounds of this class. The molecule exists in the solid state in its thione form with typical thiourea C-S and C-O bonds lengths, as well as shortened C-N bonds. The dihedral angles between the two aromatic planes are 66.93 (8) and 60.44 (9)° in the two independent molecules. An intramolecular N-H...O hydrogen bond stabilizes the molecular conformation and the crystal packing is characterized by N-H...O, O-H...S and O-H...Cl hydrogen bonds. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.004 Å; R factor = 0.045; wR factor = 0.125; data-to-parameter ratio = 16.8.
The crystal structure of the title compound, C14H8Cl4N2OS, is composed of discrete molecules with bond lengths and angles quite typical for thiourea compounds of this class. The plane containing the central SONNCC atom set subtends a dihedral angle of 31.47 (3)° with the benzene ring. An intramolecular N-H...O hydrogen bond stabilizes the molecular conformation and the molecules form centrosymmetric dimers via intermolecular N-H...S hydrogen bonds. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.032; wR factor = 0.087; data-to-parameter ratio = 17.9.
The two aromatic rings in the title compound, C15H12Cl2N2O2S, enclose a dihedral angle of 37.49 (6)°. The molecule exists in the solid state in its thione form with typical thiourea C-S and C-O bonds lengths, as well as shortened C-N bonds. An intramolecular N-H...O hydrogen bond stabilizes the molecular conformation. In the crystal, molecules are connected by N-H...O and N-H...S hydrogen bonds, forming chains running along the alpha axis. Key indicators: single-crystal X-ray study; T = 173 K; mean σ (C–C) = 0.002 Å; disorder in main residue; R factor = 0.035; wR factor = 0.087; data-to-parameter ratio = 18.9.
The title compound, Cs2Mg(H2P2O7)2·2H2O, is isostructural with the related known isoformular phosphates. The crystal framework consists of corner-sharing MgO6 and H2P2O7 polyhedra, leading to tunnels parallel to the b-axis direction in which Cs+ ions are located. The H2P2O7 unit shows a bent eclipsed conformation. The Mg2+ ion lies on an inversion center. The water molecules form hydrogen bonds to O atoms of two different dihydrogenphosphate ions, which are further hydrogen bonded to symmetry-equivalent dihydrogenphosphate ions. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(P–O) = 0.006 Å; R factor = 0.048; wR factor = 0.125; data-to-parameter ratio = 12.3.
The crystal structure of the title compound, C15H17BrN2O4S, is stabilized by intermolecular N-H...O hydrogen bonds which link the molecules into centrosymmetric dimers. The dihedral angle subtended by the 4-bromophenyl group with the mean plane passing through the hydantoin unit is 83.29 (5)°. The cyclohexyl group adopts an ideal chair conformation with the methyl group in an equatorial position. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.003 Å; R factor = 0.030; wR factor = 0.070; data-to-parameter ratio = 16.8.
The five-membered ring of the title compound, C10H14NO, is almost planar [mean deviation from best plane = 0.006 (1) Å]. The N-O bond is in the plane of the five-membered ring. The molecule is positioned about a pseudo-mirror plane at y = 0.375. In the crystal, molecules are connected by intermolecular C-H...O contacts into layers parallel to (010). Key indicators: single-crystal X-ray study; T = 167 K; mean σ(C–C) = 0.002 Å; R factor = 0.062; wR factor = 0.157; data-to-parameter ratio = 27.3.
In the title compound, C15H17ClN2O4S, the atoms in the hydantoin ring are coplanar (r.m.s. deviation = 0.006 Å). The crystal structure is stabilized by intermolecular N-H...O hydrogen bonds which link the molecules into centrosymmetric dimers. The dihedral angle subtended by the 4-chlorophenyl group with the plane passing through the hydantoin unit is 82.98 (4)°. The cyclohexyl ring adopts an ideal chair conformation. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.030; wR factor = 0.081; data-to-parameter ratio = 15.0.
In the title Grignard reagent, [MgBr(C12H9)(C5H10O)2], the Mg centre adopts a distorted tetrahedral MgCO2Br arrangement. The dihedral angle between the two aromatic rings of the biphenyl residue is 44.00 (14)°. Each molecule incorporates one R- and one S-configured 2-methyltetrahydrofuran molecule. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.007 Å; R factor = 0.045; wR factor = 0.108; data-to-parameter ratio = 17.4.
The title compound, C17H18N2O6, crystallizes with two molecules in the asymmetric unit. In both molecules, one of the C-C bonds of the pentamethylene chain connecting the two aromatic rings is in a trans conformation and another displays a gauche conformation. The aromatic rings within each molecule are nearly coplanar [dihedral angles = 3.36 (9) and 4.50 (9)°] and the nitro groups are twisted slightly out of the planes of their attached rings [dihedral angles = 8.16 (3)/6.6 (2) and 4.9 (4)/3.8 (3)°]. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.003 Å; R factor = 0.040; wR factor = 0.101; data-to-parameter ratio = 13.5.
In the title compound, C16H16BrNO4, the dihedral between the planes of the aromatic rings is 7.74 (18)°. The amide group is tilted with respect to the bromo- and methoxy-substituted aromatic rings by 36.3 (8) and 35.2 (8)°, respectively. The meta-methoxy groups are essentially in-plane with the aromatic ring [dihedral angles CH3-O-C-C = -4.6 (4) and -2.5 (4)°]. The para-methoxy group is markedly displaced from the ring plane [dihedral angle CH3-O-C-C = -72.5 (4)°]. The crystal packing is stabilized by N-H...O hydrogen bonds linking the molecules into chains running along the b axis. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.004 Å; R factor = 0.033; wR factor = 0.076; data-to-parameter ratio = 14.6.
Adamantane-1-thioamide
(2009)
The title compound, C11H17NS, is an important intermediate for the synthesis of biologically active adamantlythiazolo-oxadiazoles. The adamantyl residue is disordered about a twofold rotation axis over two sites with site-occupation factors of 0.817 (3) and 0.183 (3). The crystal structure is stabilized by intermolecular N-H...S hydrogen-bonding interactions. Key indicators: single-crystal X-ray study; T = 173 K; mean &963;(C–C) = 0.002 Å; disorder in main residue; R factor = 0.038; wR factor = 0.103; data-to-parameter ratio = 12.3.
In the title compound, C13H10N2O2, a Schiff base derivative, the dihedral angle between the two aromatic rings is 31.58 (3)°. The C=N double bond is essentially coplanar with the nitrophenyl ring. The torsion angle of the imine double bond is 175.97 (13)°, indicating that the C=N double bond is in a trans configuration. The crystal structure is stabilized by C-H...O contacts and [pi]-[pi] interactions (centroid-centroid distances of 3.807 and 3.808 Å). Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.034; wR factor = 0.093; data-to-parameter ratio = 10.3.
2-Aminopyrimidinium picrate
(2008)
The geometric parameters of the title compound, C4H6N3+·C6H2N3O7-, are in the usual ranges. While two nitro groups are almost coplanar with the aromatic picrate ring [dihedral angles 3.0 (2) and 4.4 (3)°], the third is significantly twisted out of this plane [dihedral angle 46.47 (8)°]. Anions and cations are connected via N-H...O hydrogen bonds. The molecules crystallize in planes parallel to (1\overline{2}1). Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.036; wR factor = 0.099; data-to-parameter ratio = 10.9.
The title compound, C21H16N2O2, was derived from 1-(2-hydroxyphenyl)-3-(-methoxyphenyl)propane-1,3-dione. The molecular structure of the title compound is stabilized by an intramolecular O-H...N hydrogen bond. The dihedral angle between the hydroxyphenyl ring involved in this intramolecular hydrogen bond and the pyrazole ring is significantly smaller [10.07 (6)°] than the dihedral angle between the pyrazole and the other hydroxyphenyl ring [36.64 (5)°]. The benzene ring makes a dihedral angle of 54.95 (3)° with the pyrazole ring. The crystal packing is stabilized by O-H...O and O-H...N hydrogen bonds. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.039; wR factor = 0.101; data-to-parameter ratio = 16.2.
The title compound, C22H18N2O2, was derived from 1-(2-hydroxyphenyl)-3-(4-methoxyphenyl)propane-1,3-dione. The central pyrazole ring forms dihedral angles of 16.83 (5), 48.97 (4) and 51.68 (4)°, respectively, with the methoxyphenyl, phenyl and hydroxyphenyl rings. The crystal packing is stabilized by O-H...N hydrogen bonding. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.037; wR factor = 0.096; data-to-parameter ratio = 17.0.
The title compound, C25H22O5, was obtained by a dehydrogenative carbonylation reaction. It crystallizes with one half-molecule in the asymmetric unit. The molecules have crystallographic C2 symmetry and the two atoms of the carbonyl group are located on the rotation axis. The methoxy groups are coplanar with the benzene ring to which they are attached [C-C-O-C = 1.0 (6)°]. The two furan rings are inclined at 17.3 (3)° with respect to each other and the dihedral angle between the furan ring and the benzene ring is 75.83 (12)°. The crystal structure is stabilized by C-H...O hydrogen bonds. Key indicators: single-crystal X-ray study; T = 183 K; mean ( σ(C–C) = 0.006 Å; R factor = 0.081; wR factor = 0.195; data-to-parameter ratio = 13.4.
The title molecule, C14H9ClN2OS, exists in the solid state in its amide form with a typical C=O bond length, as well as shortened C-N bonds. The plane containing the HNCO atoms subtends dihedral angles of 12.3 (4) and 8.1 (3)° with the planes of the phenyl ring and benzothiazole group, respectively, whereas the dihedral angle between the planes of the phenyl ring and the benzothiazole group is 5.96 (6)°. In the crystal, molecules form intermolecular N-H...N hydrogen bonds, generating independent scissor-like R22(8) dimers. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.028; wR factor = 0.079; data-to-parameter ratio = 13.3.
In the molecule of the title compound, C14H16ClN3O, the benzene and pyrazole rings are oriented at a dihedral angle of 3.50 (3)°. In the crystal structure, intermolecular N-H...O hydrogen bonds link the molecules into chains. A [pi]-[pi] contact between the benzene and pyrazole rings [centroid-centroid distance = 3.820 (3) Å] may further stabilize the structure. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.031; wR factor = 0.086; data-to-parameter ratio = 14.1.
2-Chloro-5-nitroaniline
(2009)
The molecule of the title compound, C6H5ClN2O2, is close to being planar (rms deviation = 0.032 Å for all non-H atoms), with a maximum deviation of -0.107 (3) Å for an O atom. In the crystal structure, intermolecular N-H...O and N-H...N interactions link the molecules into a three-dimensional network. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 A°; R factor = 0.023; wR factor = 0.061; data-to-parameter ratio = 11.8.
The geometric parameters of the title compound, C8H6N2O·C6H3N3O7, are in the usual ranges. The three nitro groups are almost coplanar with the aromatic picrate ring [dihedral angles 10.2 (2)°, 7.62 (16) and 8.08 (17)°]. The molecular conformation of the picric acid is stabilized by an intramolecular O-H...O hydrogen bond. The phthalazin-1(2H)-one molecules are connected via N-H...O hydrogen bonds, forming centrosymmetric dimers. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.034; wR factor = 0.091; data-to-parameter ratio = 11.1.
4-(4-Nitrophenoxy)biphenyl
(2009)
The two phenyl rings of the biphenyl unit of the title compound, C18H13NO3, are almost coplanar [dihedral angle 6.70 (9)°]. The nitrophenyl ring, on the other hand, is significantly twisted out of the plane of the these two rings, making dihedral angles of 68.83 (4)° with the middle ring and 62.86 (4)° with the end ring. The nitro group is twisted by 12.1 (2)° out of the plane of the phenyl ring to which it is attached. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 A° ; R factor = 0.040; wR factor = 0.118; data-to-parameter ratio = 12.8.
The six-membered ring of the title compound, C11H16NO, has a distorted envelope conformation. The piperidine N atom deviates by 0.128 (1) Å from the plane through its three neighbouring atoms. In the crystal structure, molecules are connected by intermolecular Cethynyl-H...O contacts to form chains extending in the [10\overline{1}] direction. Key indicators: single-crystal X-ray study; T = 167 K; mean σ(C–C) = 0.001 Å ; R factor = 0.040; wR factor = 0.112; data-to-parameter ratio = 27.3.
Molecules of the title compound, C40H42BrNO6, are located on a crystallographic twofold rotation axis. As a result, the nitro group and bromine residue are mutually disordered with equal occupancies. The propoxy-substituted aromatic rings are close to parallel to each other [dihedral angle = 21.24 (1)°], whereas the propenoxy-substituted rings enclose a dihedral angle of 70.44 (1)°. The dihedral angles between the methylene C atoms and the aromatic rings shows that the propenoxy substituted rings are bent away from the calixarene cavity [dihedral angle between the planes = 35.22 (8)°], whereas the propoxy-substituted rings are almost perpendicular [79.38 (10)°] to the plane of the methylene C atoms. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.006 A° ; disorder in main residue; R factor = 0.065; wR factor = 0.130; data-to-parameter ratio = 11.8.
The asymmetric unit of the title compound, [K(C3H3N2)(C12H24O6)], is composed of a potassium cation bonded to the six O atoms of a crown ether molecule and the two N atoms of a pyrazolate anion. The K...O distances range from 2.8416 (8) to 3.0025 (8) Å, and the two K...N distances are 2.7441 (11) and 2.7654 (11) Å. The K cation is displaced by 0.8437 (4) Å from the best plane through the six O atoms. The latter plane is almost perpendicular to the plane of the pyrazolate ring [dihedral angle 83.93 (3)°]. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 A°; R factor = 0.026; wR factor = 0.066; data-to-parameter ratio = 16.5.
The title compound, C14H9Cl3N2OS, has bond lengths and angles which are quite typical for thiourea compounds of this class. The molecule exists in the solid state in its thione form with typical thiourea C=S and C=O bond lengths, as well as shortened C-N bonds. An intramolecular N-H...O hydrogen bond stabilizes the molecular conformation. Intermolecular N-H...S hydrogen bonds link the molecules to form centrosymmetric dimers. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 A° ; R factor = 0.029; wR factor = 0.078; data-to-parameter ratio = 17.2.
In the paper by Bolte [Acta Cryst. (2006), E62, m1609-m1610], the chemical name in the title and the chemical diagram are incorrect. The correct title is {5-[4'-(2,2,5,5-Tetramethyl-3-pyrroline-1-oxyl-3-carbonyloxy)biphenyl-4-ylethynyl]-2,3,7,8,12,13,17,18-octaethylporphyrinato}copper(II) benzene solvate' and the correct diagram is given below.
The asymmetric unit of the title compound, C10H20I2Si2, contains two half-molecules. Both complete molecules are generated by crystallographic inversion centers located at the mid-points of the central C-C single bonds; the butadiene groups are planar, with a trans conformation about the central C-C bond. The molecules show short intramolecular H...I contacts of 2.89 and 2.92 Å. The crystal packing shows no short intermolecular contacts. Key indicators: single-crystal X-ray study; T = 155 K; mean σ(C–C) = 0.002 Å ; R factor = 0.021; wR factor = 0.059; data-to-parameter ratio = 43.6.
In the title compound, C30H34N2O6, the complete molecule is generated by a crystallographic 2/m symmetry operation. The 1-oxyl-3-pyrroline-3-carboxylate group lies on a mirror plane. The dihedral angle between the ring planes of the biphenyl fragment is constrained by symmetry to be zero, resulting in rather short intramolecular H...H contact distances of 2.02 Å. In the crystal, molecules are connected along the a-axis direction by very weak intermolecular methyl-phenyl C-H...[pi] interactions. The C-H bond is not directed to the center of the benzene ring, but mainly to one C atom [C-H...C(x - 1, y, z): H...C = 2.91 Å and C-H...C = 143°]. Key indicators: single-crystal X-ray study; T = 169 K; mean σC–C) = 0.002 Å ; R factor = 0.049; wR factor = 0.126; data-to-parameter ratio = 19.8.
Die vorliegende Arbeit befasst sich mit der Entwicklung von neuen enantioselektiven und diastereoselektiven Brønsted-Säure katalysierten Reaktionen. Das Aktivierungsprinzip entspricht dabei einer klassischen Säure-Base-Reaktion, in der eine Brønsted-Säure einen Elektronenpaar-Donor protoniert, woraus die Bildung eines Ionenpaares resultiert. Erweitert man dieses Konzept durch den Einsatz einer chiralen Protonenquelle und verwendet als Base ein prochirales Substrat, wie ein Imin, so entsteht durch dessen Protonierung ein chirales Ionenpaar, wodurch das Substrat einerseits aktiviert wird und anderseits asymmetrische Induktion über das chirale Anion erfährt. Greift in dem darauf folgenden Schritt ein Nucleophil selektiv über eine Seite des positiv geladenen Elektrophils an, so bildet sich enantioselektiv ein neues Stereozentrum. Die Natur nutzt dieses Prinzip zum Aufbau von optisch reinen α-Aminosäuren. So katalysiert die Glutamatdehydrogenase (GDH) die Darstellung von Glutaminsäure durch Protonierung des entsprechenden α-Iminoglutarats, wodurch der nachfolgende Hydrid-Angriff mittels Nicotinamidadenindinukleotid (NADH) selektiv die (L)-Aminosäure liefert. Dieses Konzept konnte während der eigenen Diplomarbeit auf die enantioselektive Brønsted-Säure katalysierte Transferhydrierung von Ketiminen übertragen werden. Dabei simuliert eine chirale Protonenquelle 1 das Enzym (GDH) und das Reduktionsmittel NADH wird durch ein synthetisches Analogon, das Hantzsch Dihydropyridin 8a ersetzt ... Die vorliegende Arbeit ist kumulativ verfasst. Der größte Teil der hier vorgestellten Ergebnisse ist bereits veröffentlicht oder zur Publikation eingereicht. Die experimentellen Daten sind Bestandteil der in Kapitel 10 aufgeführten Publikationen und werden nicht gesondert diskutiert. Folgende Teile dieser Arbeit wurden bereits veröffentlicht: Highly Enantioselective Organocatalytic Carbonyl-Ene Reaction with strongly Acid, Chiral Brønsted Acids as Efficient Catalysts Rueping M., Theissmann T., Kuenkel A., Koenigs R.M., Angewandte Chemie International Edition 2008, 47, 6798, Angewandte Chemie 2008, 120, 6903. Asymmetric counterion pair catalysis: An enantioselective Brønsted acid-catalyzed protonation Rueping M., Theissmann T., Raja S., Bats J.W., Advanced Synthesis & Catalysis 2008, 350, 1001. An enantioselective chiral brønsted acid catalyzed imino-azaenamine reaction Rueping M., Sugiono E., Theissmann T., Kuenkel A., Köckritz A., Pews-Davtyan A., Nemati N., Beller M., Organic Letters 2007, 9, 1065. Remarkably low catalyst loading in Brønsted acid catalyzed transfer hydrogenations: Enantioselective reduction of benzoxazines, benzothiazines, and benzoxazinones Rueping M., Antonchick A.P., Theissmann T., Angewandte Chemie International Edition 2006, 45, 6751, Angewandte Chemie 2006, 118, 6903. A highly enantioselective brønsted acid catalyzed cascade reaction: Organocatalytic transfer hydrogenation of quinolines and their application in the synthesis of alkaloids Rueping M., Antonchick A.P., Theissmann T., Angewandte Chemie International Edition 2006, 45, 3683, Angewandte Chemie 2006, 118, 3765. Metal-free Brønsted acid catalyzed transfer hydrogenation - New organocatalytic reduction of quinolines Rueping M., Theissmann, T., Atonchick A.P., Synlett 2006, 1071. The twinned crystal structure of diiodobis(triphenylphosphine) palladium(II) dichloromethane disolvate at 173 K Theissmann T., Bolte M., Acta Crystallographica Section E, 2006, E62, 1056. Folgende Manuskripte wurden zur Veröffentlichung eingereicht: First Enantioselective Chiral Brønsted Acid Catalyzed Synthesis of 4´-Substituted Tetrahydroquinolines Rueping M., Theissmann T., Stoeckel M., Atonchick A.P. Asymmetric Organocatalytic Reductions in the Enantioselective Synthesis of Fluoroquinolones, Flumiquine and Levofloxacin Rueping M, Stoeckel M., Theissmann T., Haack K. Synthesis and Structural Investigations of H8-BINOL-derived N-triflylphosphoramides Rueping M., Nachtsheim B.J., Koenigs R., Ieawsuwan W., Theissmann T. Buchbeitrag: Metal-free Brønsted Acid Catalyzed Transfer-Hydrogenation: Enantioselective Synthesis of Tetrahydroquinolines Rueping M., Theissmann T., Atonchick A.P., Catalysts for Fine Chemical Industry, Vol. 5, 2006
The title compound, C14H20O3, is a synthetic analogue with a long aliphatic side chain of the important food additive and flavoring agent, vanillin. There are two independent molecules in the asymmetric unit, each having an essentially planar conformation (r.m.s. deviations of 0.023 and 0.051Å for all non-H atoms of the two molecules in the asymmetric unit). Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 A°; R factor = 0.049; wR factor = 0.144; data-to-parameter ratio = 15.9.
The title compound, C20H22O2, crystallizes with two independent molecules in the asymmetric unit. In each molecule, all the non-H atoms lie in a common plane (r.m.s. deviations of 0.098 and 0.079 Å). There is a [pi]-[pi] stacking interaction in the crystal structure. The central aromatic rings of the two molecules, which are stacked head-to-tail one above the other, are separated by centroid-to-centroid distances of 3.872 (13) and 3.999 (10) Å. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.003 A° ; R factor = 0.044; wR factor = 0.101; data-to-parameter ratio = 14.6.
Das Ziel des adaptiven Entwurfs von Substanzbibliotheken ist es, die vollständige biologische Testung einer molekularen Screeningbibliothek zu vermeiden. Stattdessen erfolgt, geleitet durch Optimierungsalgorithmen, eine "intelligente" Navigation durch den chemischen Raum, um so bevorzugt Substanzen mit gewünschten Eigenschaften auszuwählen. In einer retrospektiven Studie wurden die Optimierungsalgorithmen "Zufallssuche", "Simulated Annealing", "Evolutionsstrategie" und "Partikelschwarmoptimierung" im Hinblick auf den Entwurf von Bibliotheken von Serinproteaseinhibitoren systematischen verglichen. Die Gesamtzahl verfügbarer Substanztestungen wurde auf 300 beschränkt, um Laborbedingungen zu simulieren. Als Ergebnis zeigten sich besonders die Evolutionsstrategien für einen Einsatz in einer Niedrigdurchsatzscreening-Kampagne geeignet, da diese effizient mit großen Populationen und wenigen Iterationen arbeiteten. Der zweite Teil dieser Arbeit beschreibt den erfolgreichen Entwurf einer fokussierten Bibliothek von RNA-Liganden. In einer hybriden, prospektiven Optimierungsstudie wurden nach dem Vorbild einer iterativen Niedrigdurchsatzscreening-Kampagne vom Computer vorgeschlagene Moleküle im Labor getestet. Die Substanzen wurden auf Inhibition einer spezifischen molekularen Wechselwirkung im Replikationszyklus von HIV getestet (Tat-TAR-Interaktion). In vier Generationen wurden 9 von 170 untersuchten Verbindungen positiv auf Inhibition der Tat-TAR-Interaktion getestet (Trefferquote: 5,3%), wobei lediglich 0,089% der Verbindungen der Screeningbibliothek untersucht wurden. Die zwei potentesten Kandidaten wiesen einen IC50 von 51 uM bzw. 116 uM auf.
In the title compound, C11H14O4, an intermediate for the synthesis of a new kind of estrogen receptor modulator, all non-H atoms lie on a common plane (r.m.s. deviation = 0.0472 Å). All C-C bonds in the side chain are in a trans conformation, and the hydroxyl group is also trans to the methylene chain. In the crystal structure, molecules form centrosymmetric dimers showing a head-to-head arrangement which is stabilized by O-H...O hydrogen bonds. A weak C-H...O contact is also present.
9,9-Dimethyl-9-silafluorene
(2009)
The title compound, C14H14Si, crystallizes with two almost identical molecules (r.m.s. deviation = 0.080 Å for all non-H atoms) in the asymmetric unit. All atoms of the silafluorene moiety lie in a common plane (r.m.s. deviations = 0.049 and 0.035 Å for the two molecules in the asymmetric unit). The Si-Cmethyl bonds are significantly shorter [1.865 (4)-1.868 (4) Å] than the Si-Caromatic bonds [1.882 (3)-1.892 (3) Å]. Owing to strain in the five-membered ring, the endocyclic C-Si-C angles are reduced to 91.05 (14) and 91.21 (14)°. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.005 A°; R factor = 0.061; wR factor = 0.157; data-to-parameter ratio = 16.3.
The complete molecule of the title compound, C18H24N2O2, is generated by a crystallographic inversion centre. The torsion angles in the hexamethylene chain are consistent with an antiperiplanar conformation, whereas the conformation of the O—CH2—CH2—CH2 unit is gauche. The three-dimensional crystal packing is stabilized by N—H⋯O and N—H⋯N hydrogen bonding.
The Mg centre in the title compound, [MgBr2(C2H7N)3], is pentacoordinated in a trigonal-bipyramidal mode with the two Br atoms in axial positions and the N atoms of the dimethylamine ligands in equatorial positions. The MgII centre is located on a crystallographic twofold rotation axis. The crystal structure is stabilized by N—H⋯Br hydrogen bonds. The N atom and H atoms of one dimethylamine ligand are disordered over two equally occupied positions.