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Intermolecular N (intermolecular + n)
Selected AbstractsSynthesis and X-ray structure of two conformational isomers of [Zn(medpt)(SCN)2], medpt = bis (3 , aminopropyl)methylamineCRYSTAL RESEARCH AND TECHNOLOGY, Issue 2 2006S. Guha Abstract Two conformational isomers of [Zn (medpt)(NCS)2], medpt=bis(3-aminopropyl) methylamine, (1) and (2) have been synthesised and the crystal structures are determined using single crystal X-ray diffraction. The structures of the complexes have been solved by Patterson method and refined by full-matrix least- squares techniques to R1 = 0.0524 for (1) and R1 = 0.0506 for (2), respectively. The geometry around the Zn(II) centre in both isomers is distorted trigonal bipyramidal. The two pendent thiocyanate moieties in (1), with Zn,N,C angles 167.9(4),173.9(4)º, coordinate the mental centre almost linearly while the corresponding coordinations in (2) are significantly bent [Zn,N,C angles 150.8(3),153.1(2)°]. Intermolecular N,H,S hydrogen bonds stabilise the crystal packing in the complexes forming infinite chains parallel to the [100] direction. The combinations of molecular chains generate three/two dimensional supramolecular framework in complexes (1) and (2). (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Poly[bis(,-4-benzoyl-1-isonicotinoylthiosemicarbazide-,2N:S)dichloridocadmium(II)]ACTA CRYSTALLOGRAPHICA SECTION C, Issue 5 2010Yu-Bo Wang The asymmetric unit of the title complex, [CdCl2(C14H12N4O2S)2]n, consists of one CdII ion located on the crystallographic inversion centre, one 4-benzoyl-1-isonicotinoylthiosemicarbazide ligand and one chloride ligand. The central CdII ion adopts a distorted octahedral coordination geometry formed by two pyridyl N atoms of two ligands, two S atoms of two other ligands and two chloride ligands. The thiosemicarbazide ligands act as bridges, linking the metal ions into a two-dimensional layered structure parallel to the bc plane. Intermolecular N,H...O hydrogen bonds and C,H..., interactions exist between adjacent layers. [source] 2,3-Dihydro-1,3-benzothiazol-2-iminium monohydrogen sulfate and 2-iminio-2,3-dihydro-1,3-benzothiazole-6-sulfonate: a combined structural and theoretical studyACTA CRYSTALLOGRAPHICA SECTION C, Issue 12 2009Rafal Kruszynski The 2-aminobenzothiazole sulfonation intermediate 2,3-dihydro-1,3-benzothiazol-2-iminium monohydrogen sulfate, C7H7N2S+·HSO4,, (I), and the final product 2-iminio-2,3-dihydro-1,3-benzothiazole-6-sulfonate, C7H6N2O3S2, (II), both have the endocyclic N atom protonated; compound (I) exists as an ion pair and (II) forms a zwitterion. Intermolecular N,H...O and O,H...O hydrogen bonds are seen in both structures, with bonding energy (calculated on the basis of density functional theory) ranging from 1.06 to 14.15,kcal,mol,1. Hydrogen bonding in (I) and (II) creates DDDD and C(8)C(9)C(9) first-level graph sets, respectively. Face-to-face stacking interactions are observed in both (I) and (II), but they are extremely weak. [source] A structural systematic study of four isomers of difluoro- N -(3-pyridyl)benzamideACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2009Joyce McMahon The four isomers 2,4-, (I), 2,5-, (II), 3,4-, (III), and 3,5-difluoro- N -(3-pyridyl)benzamide, (IV), all with formula C12H8F2N2O, display molecular similarity, with interplanar angles between the C6/C5N rings ranging from 2.94,(11)° in (IV) to 4.48,(18)° in (I), although the amide group is twisted from either plane by 18.0,(2),27.3,(3)°. Compounds (I) and (II) are isostructural but are not isomorphous. Intermolecular N,H...O=C interactions form one-dimensional C(4) chains along [010]. The only other significant interaction is C,H...F. The pyridyl (py) N atom does not participate in hydrogen bonding; the closest H...Npy contact is 2.71,Å in (I) and 2.69,Å in (II). Packing of pairs of one-dimensional chains in a herring-bone fashion occurs via,-stacking interactions. Compounds (III) and (IV) are essentially isomorphous (their a and b unit-cell lengths differ by 9%, due mainly to 3,4-F2 and 3,5-F2 substitution patterns in the arene ring) and are quasi-isostructural. In (III), benzene rotational disorder is present, with the meta F atom occupying both 3- and 5-F positions with site occupancies of 0.809,(4) and 0.191,(4), respectively. The N,H...Npy intermolecular interactions dominate as C(5) chains in tandem with C,H...Npy interactions. C,H...O=C interactions form R22(8) rings about inversion centres, and there are ,,, stacks about inversion centres, all combining to form a three-dimensional network. By contrast, (IV) has no strong hydrogen bonds; the N,H...Npy interaction is 0.3,Å longer than in (III). The carbonyl O atom participates only in weak interactions and is surrounded in a square-pyramidal contact geometry with two intramolecular and three intermolecular C,H...O=C interactions. Compounds (III) and (IV) are interesting examples of two isomers with similar unit-cell parameters and gross packing but which display quite different intermolecular interactions at the primary level due to subtle packing differences at the atom/group/ring level arising from differences in the peripheral ring-substitution patterns. [source] trans -Diaquabis(nicotinamide-,N)bis(salicylato-,O)cobalt(II)ACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2008The title compound, [Co(C7H5O3)2(C6H6N2O)2(H2O)2], forms a three-dimensional hydrogen-bonded supramolecular structure. The CoII ion is in an octahedral coordination environment comprising two pyridyl N atoms, two carboxylate O atoms and two O atoms from water molecules. Intermolecular N,H...O and O,H...O hydrogen bonds produce R22(8), R22(12) and R22(14) rings, which lead to two-dimensional chains. An extensive three-dimensional supramolecular network of C,H...O, N,H...O and O,H...O hydrogen bonds and C,H..., interactions is responsible for crystal structure stabilization. This study is an example of the construction of a supramolecular assembly based on hydrogen bonds in mixed-ligand metal complexes. [source] ChemInform Abstract: Asymmetric Intermolecular N,H Insertion Reaction of Phenyldiazoacetates with Anilines Catalyzed by Achiral Dirhodium(II) Carboxylates and Cinchona Alkaloids.CHEMINFORM, Issue 41 2010Hiroaki Saito Abstract A novel catalytic system consisting of a rhodium salt and dihydrocinchonine is used for the synthesis of phenylglycine derivatives (III) by asymmetric N-H insertion reaction of phenyldiazoacetate (I) with anilines (II). [source] Crystal structure of 2-(2'-hydroxyphenyl)-6-tributylstannyl-4-(3H )-quinazolinone and 2-(2'-hydroxyphenyl)-6-iodo-4-(3H)-quinazolinoneCRYSTAL RESEARCH AND TECHNOLOGY, Issue 6 2006Ketai Wang Abstract The structures of the title compounds C26H37N2O2Sn (I) and C14H9IN2O2 (II) were determined by single-crystal X-ray diffraction technique. Compound I crystallizes in the triclinic space group P1 with a = 9.560(3) Å, b = 16.899(6) Å, c = 17.872(5) Å, , = 65.957(7)°, , = 83.603(5)°, , ( = 75.242(5)°, V = 2549.8(13) Å3, Z = 4, and D =1.374 g/cm3. The compound consists of a quinazolinone ring with phenol and tributylstannyl moieties. Compound II crystallizes in the monoclinic space group P21/c with a = 7.6454(12) Å, b = 5.9270(9) Å, c = 27.975(4) Å; , = 90°, , = 95.081(3)°, , = 90°, V = 1262.7(3) Å3, Z = 4, and D = 1.915 g/cm3. The compound consists of a quinazolinone ring with phenol and iodine substituents. For both I and II, the short intramolecular O,H,N and two long intermolecular N,H,O hydrogen bonds are highly effective in holding the molecular system in a stable state. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] "Tail,Tail Dimerization" of Ferrocene Amino Acid DerivativesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 25 2010Daniel Siebler Abstract Acid anhydrides of N-protected 1,-aminoferrocene-1-carboxylic acid (Fca) have been prepared and spectroscopically characterized (protection group Boc, Fmoc, Ac; 4a,4c). The structure of the Boc-derivative 4a has been determined by single-crystal X-ray crystallography. An intramolecular N,H···O hydrogen bond involving the carbamate units results in a ring structure containing the two ferrocene units, the anhydride moiety, and the hydrogen bond. In the crystal, the individual molecules are connected by intermolecular N,H···O hydrogen bonds of the carbamate unit. Experimental and theoretical studies suggest that the ring motif is also a dominant species in solution. Electronic communication across the anhydride moiety is found to be very weak as judged from electrochemical, spectroscopic, and theoretical experiments. [source] Syntheses, Spectroscopic Studies, and Crystal Structures of Chiral [Rh(aminocarboxylato)(,4 -cod)] and Chiral [Rh(amino alcohol)(,4 -cod)](acetate) Complexes with an Example of a Spontaneous Resolution of a Racemic Mixture into Homochiral Helix-EnantiomersEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 11 2006Mohammed Enamullah Abstract The dimeric complex acetato(,4 -cycloocta-1,5-diene)rhodium(I), [Rh(O2CMe)(,4 -cod)]2 (cod = cycloocta-1,5-diene), reacts with amino acids [HAA = L -alanine, (S)-2-amino-2-phenylacetic acid (L -phenylglycine), N -methylglycine, and N -phenylglycine] and with the amino alcohol (S)-2-amino-2-phenylethanol to afford the aminocarboxylato(,4 -cycloocta-1,5-diene)rhodium(I) complexes [Rh(AA)(,4 -cod)] (AA = deprotonated amino acid = aminocarboxylato ligand) and [(S)-2-amino-2-phenylethanol](,4 -cycloocta-1,5-diene)rhodium(I) acetate, [Rh{(S)-HOCH2,CH(Ph)-NH2}(,4 -cod)](O2CMe) (V). The complexes are characterized by IR, UV/Vis, 1H/13C NMR and mass spectroscopy. The achiral N -phenylglycine ligand gives a chiral N -phenylglycinato complex [Rh(O2C,CH2,NHPh)(,4 -cod)] (IV) with the amine nitrogen atom becoming the stereogenic center upon metal coordination. Complex IV crystallizes in the tetragonal, chiral space group P43 and the crystal structure reveals twofold spontaneous resolution of a racemic mixture into homochiral helix-enantiomers. The investigated crystal contained only one type of helix, namely (left-handed or M- ) 43 -helical chains. This is traced first to an intermolecular N,H···O hydrogen bonding from the stereogenic amino group to a neighboring unligated carboxyl oxygen atom that connects only molecules of the same (R)-configuration into (left-handed or M- ) 43 -helical chains. This intrachain homochirality is supplemented, secondly, by the interlocking of adjacent chains with their corrugated van der Waals surface to allow for an interchain transmission of the sense of helicity, building the single crystal from the same homochiral helix-enantiomer. The enantiomeric amino alcohol complex V crystallizes in the monoclinic, noncentrosymmetric (Sohncke) space group P21. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Tellurated Schiff Bases Formed from {2-[(4-Methoxyphenyl)telluro]ethyl}amine and Bis(2-aminoethyl) Telluride with o -Hydroxyacetophenone: Synthesis and Complexation Reactions with HgII, PdII and RuII , Crystal Structures of the Ligands, [Ru(p -cymene)Cl{H2NCH2CH2TeC6H4 -4-OCH3}]Cl·H2O and [RuCl{4-MeOC6H4TeCH2CH2NHCH(CH3)C6H4 -2-O,}]EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 5 2004Raghavendra Kumar P. Abstract {2-[(4-Methoxyphenyl)telluro]ethyl}amine and bis(2-aminoethyl) telluride on treatment with o -hydroxyacetophenone gave the Schiff bases 4-MeOC6H4TeCH2CH2N=C(CH3)C6H4 -2-OH (L1) and 2-HOC6H4(CH3)C=NCH2CH2TeCH2CH2N=C(CH3)C6H4 -2-OH (L3), respectively. The reduction of L1 and L3 with NaBH4 resulted in 4-MeOC6H4TeCH2CH2NHCH(CH3)C6H4 -2-OH (L2) and 2-HOC6H4(CH3)CHNHCH2CH2TeCH2CH2NHCH(CH3)C6H4 -2-OH (L4), respectively, which have 1 or 2 chiral centers. The 1H and 13C NMR spectra of L1 to L4 were found to be characteristic. Treatment of L1 with [Ru(p -cymene)Cl2]2 resulted in [Ru(p -cymene)(4-MeOC6H4TeCH2CH2NH2)Cl]Cl·H2O (1) whereas in the reaction of L2 with [Ru(p -cymene)Cl2]2, the p -cymene ligand is lost resulting in [RuCl(L2 -H)] (4). The reactions of L1, L3 and L4 with HgBr2 resulted in complexes of the type [HgBr2·(L)2] while Na2PdCl4 reacted with L1 to give [PdCl(L1 -H)]. The solid-state structures of L1, L3, 1 and 4 were determined by single-crystal X-ray diffraction studies. The very swift formation of the tellurated amine from a tellurated Schiff base (L1) by hydrolysis has been observed for the first time and has resulted in 1. The Ru,N and Ru,Te bond lengths in 1 are 2.142(3) and 2.6371 (4) Å, respectively. The replacement of the p -cymene ligand with a hybrid organotellurium ligand (L2 -H), resulting in 4, is also a first example of its kind. The Ru center in 4 has a square-planar geometry, with the Ru,N, Ru,Te, Ru,O and Ru,Cl bond lengths being 2.041(6), 2.4983(8), 2.058(5) and 2.308(2) Å, respectively. In the crystals of 4 there are secondary intermolecular Te···Cl interactions and intermolecular N,H···O hydrogen bonds. This is the first example in which coordinated Te in a complex is engaged in two intermolecular secondary interactions. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Synthesis, crystal structure and spectroscopic properties of a novel carbacylamidophosphate: N -(3-nitrobenzoyl)- N,,N,,-bis(tert -butyl)phosphoric triamideACTA CRYSTALLOGRAPHICA SECTION B, Issue 4 2009Khodayar Gholivand The new compound N -(3-nitrobenzoyl)- N,,N,,-bis(tert -butyl)phosphoric triamide was synthesized by reacting 3-nitrobenzoyl phosphoramidic dichloride and tert -butyl amine, and characterized by multinuclear (1H, 13C and 31P) NMR and FTIR spectroscopy techniques. Structural and conformational properties were analyzed using single-crystal X-ray diffraction, vibrational spectra and theoretical calculations. The crystal structure contains three symmetry-independent disordered molecules, connected via intermolecular N,H...O=P and N,H...O=C hydrogen bonds to form a centrosymmetric hexameric chain extended along the [2,1,] direction. The disorder is mainly caused by rotation of the tert -butyl groups around the C,N bonds. [source] Green chemistry synthesis: 2-amino-3-[(E)-(2-pyridyl)methylideneamino]but-2-enedinitrile monohydrate and 5-cyano-2-(2-pyridyl)-1-(2-pyridylmethyl)-1H -imidazole-4-carboxamideACTA CRYSTALLOGRAPHICA SECTION C, Issue 9 2010Muhammad Altaf The title compounds, C10H9N5O·H2O (L1·H2O) and C16H12N6O (L2), were synthesized by solvent-free aldol condensation at room temperature. L1, prepared by grinding picolinaldehyde with 2,3-diamino-3-isocyanoacrylonitrile in a 1:1 molar ratio, crystallized as a monohydrate. L2 was prepared by grinding picolinaldehyde with 2,3-diamino-3-isocyanoacrylonitrile in a 2:1 molar ratio. By varying the conditions of crystallization it was possible to obtain two polymorphs, viz. L2-I and L2-II; both crystallized in the monoclinic space group P21/c. They differ in the orientation of one pyridine ring with respect to the plane of the imidazole ring. In L2-I, this ring is oriented towards and above the imidazole ring, while in L2-II it is rotated away from and below the imidazole ring. In all three molecules, there is a short intramolecular N,H...N contact inherent to the planarity of the systems. In L1·H2O, this involves an amino H atom and the C=N N atom, while in L2 it involves an amino H atom and an imidazole N atom. In the crystal structure of L1·H2O, there are N,H...O and O,H...O intermolecular hydrogen bonds which link the molecules to form two-dimensional networks which stack along [001]. These networks are further linked via intermolecular N,H...N(cyano) hydrogen bonds to form an extended three-dimensional network. In the crystal structure of L2-I, symmetry-related molecules are linked via N,H...N hydrogen bonds, leading to the formation of dimers centred about inversion centres. These dimers are further linked via N,H...O hydrogen bonds involving the amide group, also centred about inversion centres, to form a one-dimensional arrangement propagating in [100]. In the crystal structure of L2-II, the presence of intermolecular N,H...O hydrogen bonds involving the amide group results in the formation of dimers centred about inversion centres. These are linked via N,H...N hydrogen bonds involving the second amide H atom and the cyano N atom, to form two-dimensional networks in the bc plane. In L2-I and L2-II, C,H..., and ,,, interactions are also present. [source] 2,2,2-Trifluoro- N -(1a,2,7,7a-tetrahydronaphtho[2,3- b]oxiren-3-yl)acetamide by X-ray powder diffractionACTA CRYSTALLOGRAPHICA SECTION C, Issue 9 2010Mwaffak Rukiah The title compound, C12H10F3NO2, an important precursor in the preparation of benzovesamicol analogues for the diagnosis of Alzheimer's disease, was prepared by the epoxidation of 5,8-dihydronaphthalen-1-amine using 3-chloroperoxybenzoic acid. The structure was determined by X-ray powder diffraction, multinuclear NMR spectroscopy and FT,IR spectroscopy. A pair of molecules form intermolecular N,H...O hydrogen bonds, involving the amino and oxirene groups, to produce a dimer. [source] Diamminesilver(I) bis(2-amino-5-nitrobenzoato-,2O1,O1,)silver(I): a two-dimensional supramolecular sheet with a short intersheet distance containing a rare four-coordinate planar silver(I) centreACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2010Di Sun The asymmetric unit of the title compound, [Ag(NH3)2][Ag(C7H5N2O4)2], comprises half an [Ag(NH3)2]+ cation and half an [Ag(anbz)2], anion (anbz is 2-amino-5-nitrobenzoate). Both AgI ions are located on inversion centres. The cation has a linear coordination geometry with two symmetry-related ammine ligands. The AgI cation in the anionic part shows a rare four-coordinate planar geometry completed by two chelating symmetry-related anbz ligands. Intra- and intermolecular N,H...O hydrogen bonds create a slightly undulating two-dimensional supramolecular sheet. Adjacent sheets are only ca 3.3,Å apart. Ag...O, Ag...N and ,,, stacking interactions consolidate the packing of the molecules in the solid state. [source] N,N,-Diethyl-4-nitrobenzene-1,3-diamine, 2,6-bis(ethylamino)-3-nitrobenzonitrile and bis(4-ethylamino-3-nitrophenyl) sulfoneACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2010Thomas J. Payne N,N,-Diethyl-4-nitrobenzene-1,3-diamine, C10H15N3O2, (I), crystallizes with two independent molecules in the asymmetric unit, both of which are nearly planar. The molecules differ in the conformation of the ethylamine group trans to the nitro group. Both molecules contain intramolecular N,H...O hydrogen bonds between the adjacent amine and nitro groups and are linked into one-dimensional chains by intermolecular N,H...O hydrogen bonds. The chains are organized in layers parallel to (101) with separations of ca 3.4,Å between adjacent sheets. The packing is quite different from what was observed in isomeric 1,3-bis(ethylamino)-2-nitrobenzene. 2,6-Bis(ethylamino)-3-nitrobenzonitrile, C11H14N4O2, (II), differs from (I) only in the presence of the nitrile functionality between the two ethylamine groups. Compound (II) crystallizes with one unique molecule in the asymmetric unit. In contrast with (I), one of the ethylamine groups, which is disordered over two sites with occupancies of 0.75 and 0.25, is positioned so that the methyl group is directed out of the plane of the ring by approximately 85°. This ethylamine group forms an intramolecular N,H...O hydrogen bond with the adjacent nitro group. The packing in (II) is very different from that in (I). Molecules of (II) are linked by both intermolecular amine,nitro N,H...O and amine,nitrile N,H...N hydrogen bonds into a two-dimensional network in the (10) plane. Alternating molecules are approximately orthogonal to one another, indicating that ,,, interactions are not a significant factor in the packing. Bis(4-ethylamino-3-nitrophenyl) sulfone, C16H18N4O6S, (III), contains the same ortho nitro/ethylamine pairing as in (I), with the position para to the nitro group occupied by the sulfone instead of a second ethylamine group. Each 4-ethylamino-3-nitrobenzene moiety is nearly planar and contains the typical intramolecular N,H...O hydrogen bond. Due to the tetrahedral geometry about the S atom, the molecules of (III) adopt an overall V shape. There are no intermolecular amine,nitro hydrogen bonds. Rather, each amine H atom has a long (H...O ca 2.8,Å) interaction with one of the sulfone O atoms. Molecules of (III) are thus linked by amine,sulfone N,H...O hydrogen bonds into zigzag double chains running along [001]. Taken together, these structures demonstrate that small changes in the functionalization of ethylamine,nitroarenes cause significant differences in the intermolecular interactions and packing. [source] Hydrogen-bonded supramolecular networks of N,N,-bis(4-pyridylmethyl)oxalamide and 4,4,-{[oxalylbis(azanediyl)]dimethylene}dipyridinium dinitrateACTA CRYSTALLOGRAPHICA SECTION C, Issue 5 2010Gene-Hsiang Lee The molecule of N,N,-bis(4-pyridylmethyl)oxalamide, C14H14N4O2, (I) or 4py-ox, has an inversion center in the middle of the oxalamide group. Adjacent molecules are then linked through intermolecular N,H...N and C,H...O hydrogen bonds, forming an extended supramolecular network. 4,4,-{[Oxalylbis(azanediyl)]dimethylene}dipyridinium dinitrate, C14H16N4O22+·2NO3,, (II), contains a diprotonated 4py-ox cation and two nitrate counter-anions. Each nitrate ion is hydrogen bonded to four 4py-ox cations via intermolecular N,H...O and C,H...O interactions. Adjacent 4py-ox cations are linked through weak C,H...O hydrogen bonding between an ,-pyridinium C atom and an oxalamide O atom, forming a two-dimensional extended supramolecular network. [source] 4-(3,5-Dimethyl-1H -pyrazol-4-ylmethyl)-3,5-dimethyl-1H -pyrazol-2-ium dihydrogen phosphate: a combined X-ray and DFT studyACTA CRYSTALLOGRAPHICA SECTION C, Issue 4 2010Dipak K. Hazra The molecular structure of the title salt, C11H17N4+·H2PO4,, has been determined from single-crystal X-ray analysis and compared with the structure calculated by density functional theory (DFT) at the BLYP level. The crystal packing in the title compound is stabilized primarily by intermolecular N,H...O, O,H...N and O,H...O hydrogen bonds and ,,, stacking interactions, and thus a three-dimensional supramolecular honeycomb network consisting of R42(10), R44(14) and R44(24) ring motifs is established. The HOMO,LUMO energy gap (1.338,eV; HOMO is the highest occupied molecular orbital and LUMO is the lowest unoccupied molecular orbital) indicates a high chemical reactivity for the title compound. [source] 2-Amino-8-(2-deoxy-2-fluoro-,- d -arabinofuranosyl)imidazo[1,2- a][1,3,5]triazin-4(8H)-one monohydrate, a 2,-deoxyguanosine analogue with an altered Watson,Crick recognition siteACTA CRYSTALLOGRAPHICA SECTION C, Issue 4 2010Dawei Jiang The title compound, C10H12FN5O4·H2O, shows an anti glycosyl orientation [, = ,123.1,(2)°]. The 2-deoxy-2-fluoroarabinofuranosyl moiety exhibits a major C2,- endo sugar puckering (S -type, C2,- endo,C1,- exo, 2T1), with P = 156.9,(2)° and ,m = 36.8,(1)°, while in solution a predominantly N conformation of the sugar moiety is observed. The conformation around the exocyclic C4,,C5, bond is ,sc (trans, gauche), with , = ,78.3,(2)°. Both nucleoside and solvent molecules participate in the formation of a three-dimensional hydrogen-bonding pattern via intermolecular N,H...O and O,H...O hydrogen bonds; the N atoms of the heterocyclic moiety and the F substituent do not take part in hydrogen bonding. [source] 7-Amino-5-methyl-2-phenyl-6-(phenyldiazenyl)pyrazolo[1,5- a]pyrimidine crystallizes with Z, = 2: pseudosymmetry and the formation of complex sheets built from N,H...N and C,H...,(arene) hydrogen bondsACTA CRYSTALLOGRAPHICA SECTION C, Issue 3 2010Jaime Portilla The title compound, C19H16N6, crystallizes with Z, = 2 in the space group P21/n. The two molecules in the selected asymmetric unit are approximate mirror images of one another; most corresponding pairs of atoms are related by an approximate half-cell translation along [100]. Each molecule contains an intramolecular N,H...N hydrogen bond and the molecules are linked into complex sheets by a combination of two intermolecular N,H...N and four C,H...,(arene) hydrogen bonds. Comparisons are made with some other 7-aminopyrazolo[1,5- a]pyrimidines. [source] A simple hydrogen-bonded chain in (3Z)-3-{1-[(5-phenyl-1H -pyrazol-3-yl)amino]ethylidene}-4,5-dihydrofuran-2(3H)-one, and a hydrogen-bonded ribbon of centrosymmetric rings in the self-assembled adduct (3Z)-3-{1-[(5-methyl-1H -pyrazol-3-yl)amino]ethylidene}-4,5-dihydrofuran-2(3H)-one,6-(2-hydroxyethyl)-2,5-dimethylpyrazolo[1,5- a]pyrimidin-7(4H)-one (1/1)ACTA CRYSTALLOGRAPHICA SECTION C, Issue 1 2010Jairo Quiroga (3Z)-3-{1-[(5-Phenyl-1H -pyrazol-3-yl)amino]ethylidene}-4,5-dihydrofuran-2(3H)-one, C15H15N3O2, (I), and the stoichiometric adduct (3Z)-3-{1-[(5-methyl-1H -pyrazol-3-yl)amino]ethylidene}-4,5-dihydrofuran-2(3H)-one,6-(2-hydroxyethyl)-2,5-dimethylpyrazolo[1,5- a]pyrimidin-7(4H)-one (1/1), C10H13N3O2·C10H13N3O2, (II), in which the two components have the same composition but different constitutions, are formed in the reactions of 2-acetyl-4-butyrolactone with 5-amino-3-phenyl-1H -pyrazole and 5-amino-3-methyl-1H -pyrazole, respectively. In each compound, the furanone component contains an intramolecular N,H...O hydrogen bond. The molecules of (I) are linked into a chain by a single intermolecular N,H...O hydrogen bond, while in (II), a combination of one O,H...N hydrogen bond, within the selected asymmetric unit, and two N,H...O hydrogen bonds link the molecular components into a ribbon containing alternating centrosymmetric R44(20) and R66(22) rings. [source] Two two-dimensional hydrogen-bonded coordination networks: bis(3-carboxybenzoato-,O)bis(4-methyl-1H -imidazole-,N3)copper(II) and bis(3-methylbenzoato-,N)bis(4-methyl-1H -imidazole-,N3)copper(II) monohydrateACTA CRYSTALLOGRAPHICA SECTION C, Issue 12 2009Ziliang Wang The title two-dimensional hydrogen-bonded coordination compounds, [Cu(C8H5O4)2(C4H6N2)2], (I), and [Cu(C8H7O2)2(C4H6N2)2]·H2O, (II), have been synthesized and structurally characterized. The molecule of complex (I) lies across an inversion centre, and the Cu2+ ion is coordinated by two N atoms from two 4-methyl-1H -imidazole (4-MeIM) molecules and two O atoms from two 3-carboxybenzoate (HBDC,) anions in a square-planar geometry. Adjacent molecules are linked through intermolecular N,H...O and O,H...O hydrogen bonds into a two-dimensional sheet with (4,4) topology. In the asymmetric part of the unit cell of (II) there are two symmetry-independent molecules, in which each Cu2+ ion is also coordinated by two N atoms from two 4-MeIM molecules and two O atoms from two 3-methylbenzoate (3-MeBC,) anions in a square-planar coordination. Two neutral complex molecules are held together via N,H...O(carboxylate) hydrogen bonds to generate a dimeric pair, which is further linked via discrete water molecules into a two-dimensional network with the Schläfli symbol (43)2(46,66,83). In both compounds, as well as the strong intermolecular hydrogen bonds, ,,, interactions also stabilize the crystal stacking. [source] 2,-Deoxy-5-propynyluridine: a nucleoside with two conformations in the asymmetric unitACTA CRYSTALLOGRAPHICA SECTION C, Issue 12 2009Simone Budow The title compound, 1-(2-deoxy-,- d - erythro -pentofuranosyl)-5-(prop-1-ynyl)pyrimidin-2,4(1H,3H)-dione, C12H14N2O5, shows two conformations in the crystalline state: conformer 1 adopts a C2,- endo (close to 2E; S -type) sugar pucker and an anti nucleobase orientation [, = ,134.04,(19)°], while conformer 2 shows an S sugar pucker (twisted C2,- endo,C3,- exo), which is accompanied by a different anti base orientation [, = ,162.79,(17)°]. Both molecules show a +sc (gauche, gauche) conformation at the exocyclic C4,,C5, bond and a coplanar orientation of the propynyl group with respect to the pyrimidine ring. The extended structure is a three-dimensional hydrogen-bond network involving intermolecular N,H...O and O,H...O hydrogen bonds. Only O atoms function as H-atom acceptor sites. [source] Three-dimensional networks in bis(imidazolium) 2,2,-dithiodibenzoate and 4-methylimidazolium 2-[(2-carboxyphenyl)disulfanyl]benzoateACTA CRYSTALLOGRAPHICA SECTION C, Issue 9 2009Linheng Wei Cocrystallization of imidazole or 4-methylimidazole with 2,2,-dithiodibenzoic acid from methanol solution yields the title 2:1 and 1:1 organic salts, 2C3H5N2+·C14H10O4S22,, (I), and C4H7N2+·C14H10O4S2,, (II), respectively. Compound (I) crystallizes in the monoclinic C2/c space group with the mid-point of the S,S bond lying on a twofold axis. The component ions in (I) are linked by intermolecular N,H...O hydrogen bonds to form a two-dimensional network, which is further linked by C,H...O hydrogen bonds into a three-dimensional network. In contrast, by means of N,H...O, N,H...S and O,H...O hydrogen bonds, the component ions in (II) are linked into a tape and adjacent tapes are further linked by ,,,, C,H...O and C,H..., interactions, resulting in a three-dimensional network. [source] Nonmerohedrally twinned 6-amino-3-methyluracil-5-carbaldehyde: a hydrogen-bonded ribbon containing four types of ringACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2009José M. de la Torre In the title compound [systematic name: 6-amino-5-formyl-3-methylpyrimidine-2,4(1H,3H)-dione], C6H7N3O3, the intramolecular dimensions provide evidence for some polarization of the electronic structure. There is an intramolecular N,H...O hydrogen bond; this and a combination of three intermolecular N,H...O hydrogen bonds generate an almost planar ribbon containing S(6), R22(4), R21(6) and R44(16) rings. These ribbons are linked into sheets by a dipolar carbonyl,carbonyl interaction. The structure was refined as a nonmerohedral twin, with twin fractions 0.7924,(1) and 0.2076,(10). [source] The new three-dimensional supramolecule bis{,-2-[(4-hydroxybenzoyl)hydrazonomethyl]phenolato}bis[aquacopper(II)] dinitrateACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2008Hua Yin In the title centrosymmetric binuclear complex, [Cu2(C14H11N2O3)2(H2O)2](NO3)2, the two metal centres are bridged by the phenolate O atoms of the ligand, forming a Cu2O2 quadrangle. Each Cu atom has a distorted square-pyramidal geometry, with the basal donor atoms coming from the O,N,O,-tridentate ligand and a symmetry-related phenolate O atom. The more weakly bound apical donor O atom is supplied by a coordinated water molecule. When a further weak Cu...O interaction with the 4-hydroxy O atom of a neighbouring cation is considered, the extended coordination sphere of the Cu atom can be described as distorted octahedral. This interaction leads to two-dimensional layers, which extend parallel to the (100) direction. The two-dimensional polymeric structure contrasts with other reported structures involving salicylaldehyde benzoylhydrazone ligands, which are usually discrete mono- or dinuclear Cu complexes. The nitrate anions are involved in a three-dimensional hydrogen-bonding network, featuring intermolecular N,H...O and O,H...O hydrogen bonds. [source] A structural systematic study of three isomers of difluoro- N -(4-pyridyl)benzamideACTA CRYSTALLOGRAPHICA SECTION C, Issue 9 2008Joyce McMahon The isomers 2,3-, (I), 2,4-, (II), and 2,5-difluoro- N -(4-pyridyl)benzamide, (III), all with formula C12H8F2N2O, all exhibit intramolecular C,H...O=C and N,H...F contacts [both with S(6) motifs]. In (I), intermolecular N,H...O=C interactions form one-dimensional chains along [010] [N...O = 3.0181,(16),Å], with weaker C,H...N interactions linking the chains into sheets parallel to the [001] plane, further linked into pairs via C,H...F contacts about inversion centres; a three-dimensional herring-bone network forms via C,H...,(py) (py is pyridyl) interactions. In (II), weak aromatic C,H...N(py) interactions form one-dimensional zigzag chains along [001]; no other interactions with H...N/O/F < 2.50,Å are present, apart from long N/C,H...O=C and C,H...F contacts. In (III), N,H...N(py) interactions form one-dimensional zigzag chains [as C(6) chains] along [010] augmented by a myriad of weak C,H...,(arene) and O=C...O=C interactions and C,H...O/N/F contacts. Compound (III) is isomorphous with the parent N -(4-pyridyl)benzamide [Noveron, Lah, Del Sesto, Arif, Miller & Stang (2002). J. Am. Chem. Soc.124, 6613,6625] and the three 2/3/4-fluoro- N -(4-pyridyl)benzamides [Donnelly, Gallagher & Lough (2008). Acta Cryst. C64, o335,o340]. The study expands our series of fluoro(pyridyl)benzamides and augments our understanding of the competition between strong hydrogen-bond formation and weaker influences on crystal packing. [source] Polymorphism and solvolysis of 2-cyano-3-[4-(N,N -diethylamino)phenyl]prop-2-enethioamideACTA CRYSTALLOGRAPHICA SECTION C, Issue 11 2004Vladimir N. Nesterov Two new polymorph forms, (Ia) and (Ib), of the title compound, C14H17N3S, and its solvate with acetonitrile, C14H17N3S·0.25C2H3N, (Ic), have been investigated. Crystals of the two polymorphs were grown from different solvents, viz. ethanol and N,N -dimethylformamide, respectively. The polymorphs have different orientations of the thioamide group relative to the CN substituent, with s-cis and s-trans geometry of the C=C,C=S diene fragment, respectively. Compound (Ic) contains two independent molecules, A and B, with s-cis geometry, and the solvate molecule lies on a twofold axis. The core of each molecule is slightly non-planar; the dihedral angles between the conjugated C=C,CN linkage and the phenyl ring, and between this linkage and the thioamide group are 13.4,(2) and 12.0,(2)° in (Ia), 14.0,(2) and 18.2,(2)° in (Ib), 2.3,(3) and 12.7,(4)° in molecule A of (Ic), and 23.2,(3) and 8.1,(4)° in molecule B of (Ic). As a result of strong conjugation between donor and acceptor parts, the substituted phenyl rings have noticeable quinoid character. In (Ib), there exists a very strong intramolecular steric interaction (H,H = 1.95,Å) between the bridging and thioamide parts of the molecule, which makes such a form less stable. In the crystal structure of (Ia), intermolecular N,H,N and N,H,S hydrogen bonds link molecules into infinite tapes along the [10] direction. In (Ib), such intermolecular hydrogen bonds link molecules into infinite (101) planes. In (Ic), intermolecular N,H,N hydrogen bonds link molecules A and B into dimers, which are connected via N,H,S hydrogen bonds and form infinite chains along the c direction. [source] 2-Amino-4-(1-naphthyl)-5-oxo-5,6,7,8-tetrahydro-4H -chromene-3-carbonitrile and 2-amino-7,7-dimethyl-4-(1-naphthyl)-5-oxo-5,6,7,8-tetrahydro-4H -chromene-3-carbonitrileACTA CRYSTALLOGRAPHICA SECTION C, Issue 5 2004Vladimir N. Nesterov Syntheses and X-ray structural investigations have been carried out for the two title compounds, C20H16N2O2, (IIIa), and C22H20N2O2, (IIIb). In (IIIa), the heterocyclic ring adopts a sofa conformation, while in (IIIb), the ring has a flattened boat conformation. In both molecules, the fused cyclohexenone ring adopts a sofa conformation. The dihedral angles between these two flat fragments are 3.5,(2) and 17.5,(2)° in (IIIa) and (IIIb), respectively. The dihedral angles between the pseudo-axial naphthalene substituents and the planes of the pyran rings are 90.9,(1) and 96.7,(1)°, respectively. In the crystal structure of (IIIa), intermolecular N,H,N and N,H,O hydrogen bonds link the molecules into infinite tapes along the b axis, while molecules of (IIIb) form centrosymmetric dimers via N,H,N hydrogen bonds, with only one H atom of the NH2 donor group taking part in hydrogen bonding. [source] Bis(2-aminopyridine- N)bis(benzoato- O)zincACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2000S. Shanmuga Sundara Raj The crystal structure of the title compound, [Zn-(C7H5O2)2(C5H6N2)2], is built of monomeric [Zn(2-apy)2(OBz)2] molecules (apy is aminopyridine and OBz is benzoate). The Zn atom lies on a twofold symmetry axis and adopts a slightly distorted tetrahedral coordination. The Zn,O distances to the non-coordinated O atoms are long at 2.872,(3),Å. Each non-ligating carbonyl O atom of the benzoate anion accepts one intramolecular and one intermolecular hydrogen bond from the amino group. The molecules form a chain along the c axis through intermolecular N,H,O hydrogen bonds between the amino and carboxyl groups. [source] 3-Acetyl-4-benzoyl-2-methyl-5-phenyl-3,3a-dihydropyrazolo[2,3- c]pyrimidine-7(6H)-thioneACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2000Mehmet Akkurt The molecule of the title compound, C22H19N3O2S, is not planar. The dihedral angle between the two phenyl rings is 27.46,(7)° and in the dihydropyrazolopyrimidine ring the total puckering amplitude QT is 0.526,(3),Å. The structure is stabilized by both intra- and intermolecular C,H,O interaction, and by an intermolecular N,H,S hydrogen bond. [source] | ||||||||||