Alan R Kennedy

University of Strathclyde, Glasgow, Scotland, United Kingdom

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Publications (480)1488.29 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Proton transfer to the sulfa drug sulfadiazine [systematic name: 4-amino-N-(pyrimidin-2-yl)benzenesulfonamide] gave eight salt forms. These are the monohydrate and methanol hemisolvate forms of the chloride (2-{[(4-azaniumylphenyl)sulfonyl]azanidyl}pyrimidin-1-ium chloride monohydrate, C10H11N4O2S+·Cl−·H2O, (I), and 2-{[(4-azaniumylphenyl)sulfonyl]azanidyl}pyrimidin-1-ium chloride methanol hemisolvate, C10H11N4O2S+·Cl−·0.5CH3OH, (II)); a bromide monohydrate (2-{[(4-azaniumylphenyl)sulfonyl]azanidyl}pyrimidin-1-ium bromide monohydrate, C10H11N4O2S+·Br−·H2O, (III)), which has a disordered water channel; a species containing the unusual tetraiodide dianion [bis(2-{[(4-azaniumylphenyl)sulfonyl]azanidyl}pyrimidin-1-ium) tetraiodide, 2C10H11N4O2S+·I42−, (IV)], where the [I4]2− ion is located at a crystallographic inversion centre; a tetrafluoroborate monohydrate (2-{[(4-azaniumylphenyl)sulfonyl]azanidyl}pyrimidin-1-ium tetrafluoroborate monohydrate, C10H11N4O2S+·BF4−·H2O, (V)); a nitrate (2-{[(4-azaniumylphenyl)sulfonyl]azanidyl}pyrimidin-1-ium nitrate, C10H11N4O2S+·NO3−, (VI)); an ethanesulfonate {4-[(pyrimidin-2-yl)sulfamoyl]anilinium ethanesulfonate, C10H11N4O2S+·C2H5SO3−, (VII)}; and a dihydrate of the 4-hydroxybenzenesulfonate {4-[(pyrimidin-2-yl)sulfamoyl]anilinium 4-hydroxybenzenesulfonate dihydrate, C10H11N4O2S+·HOC6H4SO3−·2H2O, (VIII)}. All these structures feature alternate layers of cations and of anions where any solvent is associated with the anion layers. The two sulfonate salts are protonated at the aniline N atom and the amide N atom of sulfadiazine, a tautomeric form of the sulfadiazine cation that has not been crystallographically described before. All the other salt forms are instead protonated at the aniline group and on one N atom of the pyrimidine ring. Whilst all eight species are based upon hydrogen-bonded centrosymetric dimers with graph set R22(8), the two sulfonate structures also differ in that these dimers do not link into one-dimensional chains of cations through NH3-to-SO2 hydrogen-bonding interactions, whilst the other six species do. The chloride methanol hemisolvate and the tetraiodide are isostructural and a packing analysis of the cation positions shows that the chloride monohydrate structure is also closely related to these.
    Acta Crystallographica Section C. 09/2014;
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    ABSTRACT: Using structurally defined potassium- tetra(alkyl)magnesiates, a new straightforward methodology to promote regioselective Mg-H exchange reactions of a wide range of aromatic and heteroaromatic substrates is disclosed. Contacted ion pair intermediates are likely to be involved, with K being the key to facilitate the magnesiation processes.
    Chemical Communications 09/2014; · 6.38 Impact Factor
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    ABSTRACT: A general thermolysis reaction for the transformation of Group 1 TMP compounds (LiTMP, NaTMP, KTMP) to 1-aza-allylic TTHP derivatives is reported. TMEDA accelerates the reaction and produces the crystalline complexes [(TMEDA)LiTTHP] and [(TMEDA·NaTTHP)2]. Methane elimination during the transformational process was confirmed via TVA coupled to MS.
    Chemical communications (Cambridge, England). 07/2014;
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    ABSTRACT: A general thermolysis reaction for the transformation of Group 1 TMP compounds (LiTMP, NaTMP, KTMP) to 1-aza-allylic TTHP derivatives is reported. TMEDA accelerates the reaction and produces the crystalline complexes [(TMEDA)LiTTHP] and [(TMEDANaTTHP)2]. Methane elimination during the transformational process was confirmed via TVA coupled to MS.
    Chemical Communications 07/2014; · 6.38 Impact Factor
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    ABSTRACT: A systematic study both in the solid- and solution-state, was carried out for a series of sodium magnesiates containing the utility amide ligand 1,1,1,3,3,3-hexamethyldisilazide (HMDS). The first complex considered is the donor-free bisamido monoalkyl polymeric complex [Na(μ-HMDS)2Mg((n)Bu)]∞. The reactivity of with common tertiary bidentate donors including N,N,N',N'-tetramethylethylenediamine (TMEDA) or its chiral relative (1R,2R)-tetramethylcyclohexyldiamine [(R,R)-TMCDA] is detailed. Surprisingly, the products of these reactions are not simple diamine adducts but are solvent separated sodium magnesiate systems [(TMEDA)2·Na](+)[Mg(HMDS)3](-) and [{(R,R)-TMCDA}2·Na](+)[Mg(HMDS)3](-). By concentrating on the likely equilibria which may give rise to formation of , a potential intermediate complexed ion pair [{(TMEDA)2·Na}(μ-(n)Bu)Mg(HMDS)2] was isolated. Additionally, the novel "inverse magnesiates" [{Na(μ-HMDS)}2Mg(μ-(n)Bu)2·(TMEDA)]∞ and [{Na(μ-HMDS)}2Mg(μ-(n)Bu)2·{(R,R)-TMCDA}]∞, were obtained by reacting solutions of composition "NaMg(HMDS)((n)Bu)2" (a likely by-product in the formation of from ), with TMEDA or (R,R)-TMCDA. The structure and nature of these bimetallic complexes have been determined using a combination of X-ray crystallographic studies and multinuclear NMR spectroscopy.
    Dalton Transactions 07/2014; · 3.81 Impact Factor
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    ABSTRACT: Expanding the synthetic potential of Mg–Zn hybrid organyl reagents (generated via transmetallation reactions), this study uncovers a versatile approach, involving a sequence of direct Zn–I exchange and Pd catalysed cross-coupling reactions which grants access to a wide range of asymmetric bis(aryls). By combining X-ray crystallography with ESI-MS and non-deuterium NMR spectroscopic studies, new light is shed on the heterobimetallic constitution of the intriguing organometallic species [(THF)4MgCl2Zn(tBu)Cl] (1) and [{Mg2Cl3(THF)6}+{ZntBu3}−] (2), formed through transmetallation of tBuMgCl with n equivalent amounts of ZnCl2 (n = 1 and 3 respectively). Operating by cooperative effects, alkyl-rich hybrid 2 can effectively promote direct Zn–I exchange reactions with aromatic halides in short periods of time at room temperature in THF solution. The structural elucidation of key organometallic intermediates involved in some of these Zn–I exchanges, provides new reactivity insights into how these bimetallic systems operate. Thus, while the reaction of 2 with 3 equivalents of 2-iodoanisole (3b) gives magnesium dizincate [{Mg(THF)6}2+{Zn(o-C6H4-OMe)3}2−] (4) which demonstrates the 3-fold activation of the tBu groups attached to Zn in 2, using 2-iodobenzonitrile (3i), only two tBu groups react with the substrate, affording [(THF)4MgCl(NC-o-C6H4)ZnI(o-C6H4-CN)(THF)] (7). In 7 Mg and Zn are connected by an aryl bridge, suggesting that the formation of contacted ion-pair hybrids may have a deactivating effect on the outcome of the Zn–I exchange process. A wide range of homoleptic tris(aryl) zincate intermediates have been prepared in situ and used as precursors in Pd catalysed cross-coupling reactions, affording bis(aryls) 6a–s in excellent yields under mild reaction conditions without the need of any additive or polar cosolvent such as NMP or DMI.
    Chemical Science 06/2014; · 8.31 Impact Factor
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    ABSTRACT: Previously it was reported that activation of (t)Bu2Zn by [(TMEDA)Na(μ-dpa)]2 led to tert-butylation of benzophenone at the challenging para-position, where the sodium amide functions as a metalloligand towards (t)Bu2Zn manifested in crystalline [{(TMEDA)Na(dpa)}2Zn(t)Bu2] (TMEDA is N,N,N',N'-tetramethylethylenediamine, dpa is 2,2'-dipyridylamide). Here we find altering the Lewis donor or alkali metal within the metalloligand dictates the reaction outcome, exhibiting a strong influence on alkylation yields and reaction selectivity. Varying the former led to the synthesis of three novel complexes, [(PMDETA)Na(dpa)]2, [(TMDAE)Na(dpa)]2, and [(H6-TREN)Na(dpa)], characterised through combined structural, spectroscopic and theoretical studies [where PMDETA is N,N,N',N'',N''-pentamethyldiethylenetriamine, TMDAE is N,N,N',N'-tetramethyldiaminoethylether and H6-TREN is N',N'-bis(2-aminoethyl)ethane-1,2-diamine]. Each new sodium amide can function as a metalloligand to generate a co-complex with (t)Bu2Zn. Reacting these new co-complexes with benzophenone proved solvent dependent with yields in THF much lower than those in hexane. Most interestingly, sub-stoichiometric amounts of the metalloligands [(TMEDA)Na(dpa)]2 and [(PMEDTA)Na(dpa)]2 with 1 : 1, (t)Bu2Zn-benzophenone mixtures produced good yields of the challenging 1,6-tert-butyl addition product in hexane (52% and 53% respectively). Although exchanging Na for Li gave similar reaction yields, the regioselectivity was significantly compromised; whereas the K system was completely unreactive. Replacing (t)Bu2Zn with (Me3SiCH2)2Zn shut down the alkylation of benzophenone; in contrast, (t)BuLi generates only the reduction product, benzhydrol. Zincation of the parent amine dpa(H) generated the crystalline product [Zn(dpa)2], as structurally elucidated through X-ray crystallography and theoretical calculations. Although the reaction mechanism for the alkylation of benzophenone remains unclear, incorporation of the radical scavenger TEMPO (2,2,6,6-tetramethylpiperidine-N-oxyl radical) into the reaction system completely inhibits benzophenone alkylation.
    Dalton Transactions 06/2014; · 3.81 Impact Factor
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    ABSTRACT: Using an interlocking co-complexation approach, a homologous series of unsolvated alkali-metal zincates [MZn(CH2SiMe3)3] (M = Li , Na , K ) was prepared by reacting equimolar amounts of Zn(CH2SiMe3)2 with the relevant alkali-metal alkyl M(CH2SiMe3) employing non-coordinating hexane as a solvent. X-ray crystallographic studies reveal that these heterobimetallic compounds exhibit unprecedented supramolecular assemblies made up exclusively of a three-fold combination of M-CH2, Zn-CH2 and MMe interactions. Revealing an important alkali-metal effect, displays a linear chain structure; whereas and form much more intricate 3D and 2D coordination networks respectively. Shedding new light into the formation of these solvent-free zincates, DFT calculations indicate that the infinite degree of aggregation observed in plays a major role in thermodynamically driving the co-complexation reactions of their homometallic precursors. NMR spectroscopic studies suggest that in C6D6 solution exist as discrete contacted ion-pair species, where the alkali-metal is partially solvated by molecules of deuterated solvent. The supramolecular assemblies of can be easily deaggregated by adding the polydentate N-donors PMDETA (N,N,N',N'',N''-pentamethyldiethylenetriamine) or TMEDA (N,N,N',N'-tetramethylethylenediamine), affording monomeric [(PMDETA)LiZn(CH2SiMe3)3] () and [(TMEDA)2NaZn(CH2SiMe3)3] ().
    Dalton Transactions 06/2014; · 3.81 Impact Factor
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    ABSTRACT: Reported here are the single-crystal X-ray structure analyses of bis-μ-methanol-κ(4)O:O-bis{[hydrotris(3-phenyl-2-sulfanylidene-2,3-dihydro-1H-1,3-imidazol-1-yl)borato-κ(3)H,S,S'](methanol-κO)sodium(I)}, [Na2(C27H22BN6S3)2(CH4O)4] (NaTm(Ph)), bis-μ-methanol-κ(4)O:O-bis{[hydrotris(3-isopropyl-2-sulfanylidene-2,3-dihydro-1H-1,3-imidazol-1-yl)borato-κ(3)H,S,S'](methanol-κO)sodium(I)}-diethyl ether-methanol (1/0.3333/0.0833), [Na2(C18H28BN6S3)2(CH4O)4]·0.3333C4H10O·0.0833CH3OH (NaTm(iPr)), and a novel anhydrous form of sodium hydrotris(methylthioimidazolyl)borate, poly[[μ-hydrotris(3-methyl-2-sulfanylidene-2,3-dihydro-1H-1,3-imidazol-1-yl)borato]sodium(I)], [Na(C12H16BN6S3)] ([NaTm(Me)]n). NaTm(iPr) and NaTm(Ph) have similar dimeric molecular structures with κ(3)H,S,S'-bonding, but they differ in that NaTm(Ph) is crystallographically centrosymmetric (Z' = 0.5) while NaTm(iPr) contains one crystallographically centrosymmetric dimer and one dimer positioned on a general position (Z' = 1.5). [NaTm(Me)]n is a one-dimensional coordination polymer that extends along the a direction and which contains a hitherto unseen side-on η(2)-C=S-to-Na bond type. An overview of the structural preferences of alkali metal soft scorpionate complexes is presented. This analysis suggests that these thione-based ligands will continue to be a rich source of interesting alkali metal motifs worthy of isolation and characterization.
    Acta crystallographica. Section C, Structural chemistry. 05/2014; 70(Pt 5):421-7.
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    ABSTRACT: The title compound, C11H8N2O3S, shows two mol-ecules per asymmetric unit, with the dihedral angles between the benzene and thio-phene rings of 13.53 (6) and 8.50 (5)° being a notable difference between them. An intra-molecular N-H⋯O hydrogen-bond in each mol-ecule generates an S(6) ring motif. The crystal packing shows no classical hydrogen bonds with the mol-ecules being packed to form weak C-H⋯O and C-H⋯S inter-actions leading to R 2 (2)(9) and R 4 (4)(25) rings which are edge-shared, giving layers parallel to (010).
    Acta Crystallographica Section E Structure Reports Online 05/2014; 70(Pt 5):o613. · 0.35 Impact Factor
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    ABSTRACT: Synthetically important for introducing a picolyl scaffold into a molecular construction, alkali metallated picoline (methylpyridine) complexes are also interesting in their own right for the diversity of their ligand-metal bonding possibilities. Here the syntheses of seven new such complexes are reported: namely three 4-picoline derivatives 4-picLi·Me6TREN, , 4-picNa·Me6TREN, , and [4-picK·2(4-picH)]∞, ; and four 2-picoline derivatives, 2-picLi·Me6TREN, , 2-picLi·PMDETA, , 2-picNa·Me6TREN, , and [2-picK·PMDETA]2, [where pic = NC5H4(CH2); Me6TREN = tris(N,N-dimethyl-2-aminoethyl)amine, (Me2NCH2CH2)3N; PMDETA = N,N,N',N'',N''-pentamethyldiethylenetriamine, (Me2NCH2CH2)2NMe]. X-ray crystallographic studies establish that the lighter alkali metal complexes , , and adopt monomeric structures in contrast to the polymeric and dimeric arrangements adopted by potassium complexes and respectively. All complexes have also been characterized by solution NMR spectroscopy ((1)H, (13)C, and where relevant (7)Li). This study represents the first example of sodium and potassium picolyl complexes to be isolated and characterized. DOSY (Diffusion-Ordered Spectroscopy) experiments performed on and suggest both compounds retain their monomeric constitutions in C6D6 solution. Discussion focuses on the influence of the metal and neutral donor molecule on the structures and the nature of the ligand-metal (enamido versus aza-allylic) interactions.
    Dalton Transactions 04/2014; · 3.81 Impact Factor
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    ABSTRACT: Despite their enormous synthetic relevance, the use of polar organolithium and Grignard reagents is greatly limited by their requirements of low temperatures in order to control their reactivity as well as the need of dry organic solvents and inert atmosphere protocols to avoid their fast decomposition. Breaking new ground on the applications of these commodity organometallics in synthesis under more environmentally friendly conditions, this work introduces deep eutetic solvents (DESs) as a green alternative media to carry out chemoselective additions of ketones in air at room temperature. Comparing their reactivities in DES with those observed in pure water suggest that a kinetic activation of the alkylating reagents is taking place, favoring nucleophilic addition over the competitive hydrolysis, which can be rationalized through formation of halide-rich magnesiate or lithiate species.
    Angewandte Chemie 04/2014;
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    ABSTRACT: Despite their enormous synthetic relevance, the use of polar organolithium and Grignard reagents is greatly limited by their requirements of low temperatures in order to control their reactivity as well as the need of dry organic solvents and inert atmosphere protocols to avoid their fast decomposition. Breaking new ground on the applications of these commodity organometallics in synthesis under more environmentally friendly conditions, this work introduces deep eutetic solvents (DESs) as a green alternative media to carry out chemoselective additions of ketones in air at room temperature. Comparing their reactivities in DES with those observed in pure water suggest that a kinetic activation of the alkylating reagents is taking place, favoring nucleophilic addition over the competitive hydrolysis, which can be rationalized through formation of halide-rich magnesiate or lithiate species.
    Angewandte Chemie International Edition 04/2014; · 11.34 Impact Factor
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    ABSTRACT: This work details a crystal engineering strategy to obtain a novel solid form of the liquid drug molecule propofol using isonicotinamide as a cocrystal former. Knowledge of intermolecular hydrogen bonded supramolecular synthons has been exploited to select a potential cocrystal former based on the likely growth unit formed. The structure of the cocrystal, solved using single-crystal X-ray diffraction, is reported, confirming the molecular packing and key intermolecular interactions adopted in the novel solid form. The potential to enhance a drug’s properties is demonstrated by an increased melting point compared to the native drug form, such that the liquid drug becomes a stable solid at room temperature. Unusually, the propofol/isonicotinamide complex has three structurally similar, temperature-dependent polymorphs, and the crystal structure of each form is reported herein.
    Crystal Growth & Design 04/2014; 14(5):2422–2430. · 4.69 Impact Factor
  • Christopher A. Dodds, Alan R. Kennedy
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    ABSTRACT: The synthesis and characterization of three N-heterocyclic carbene (NHC) complexes of copper(I) thiocyanate [Cu(IMes)(NCS)]2 (1), [Cu(IXy)(NCS)]2 (2), and [Cu(IPr)(NCS)] (3) [IMes = 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene, IXy = 1,3-bis(2,6-dimethylphenyl)imidazol-2-ylidene, IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene] are described. Single crystal diffraction and IR spectroscopy shows that reaction of one equivalent of sodium thiocyanate with [Cu(NHC)Cl] results in the formation of solid-state centrosymmetric dimers for 1 and 2 with bridging thiocyanate ligands bound through both N and S. In contrast, the equivalent reaction with IPr gives a monomeric species with N bound thiocyanate. In the solution state, all the structures of complexes 1–3 would appear to be monomeric, as evidenced by both solution state FT-IR and 13C NMR spectroscopic studies. In addition the precursor to complex 2 [Cu(IXy)Cl] (4) was structurally characterized by X-ray diffraction revealing a one-dimensional chain structure that propagates through C–H···Cl intermolecular interactions with both methyl and aromatic hydrogen atoms.
    Zeitschrift für anorganische Chemie 03/2014; · 1.16 Impact Factor
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    ABSTRACT: In the title nitroaryl benzoate derivative, C14H9NO5, the aromatic rings form a dihedral angle of 46.37 (8)°. The central ester moiety, -C-(C=O)-O-, is essentially planar (r.m.s. deviation for all non-H atoms = 0.0283 Å) and forms a dihedral angle of 54.06 (9)° with the 4-formyl-2-nitro-phenyl ring and 7.99 (19)° with the benzoate ring. In the crystal, mol-ecules are inter-twined by weak C-H⋯O inter-actions, forming helical chains along [100].
    Acta Crystallographica Section E Structure Reports Online 03/2014; 70(Pt 3):o268. · 0.35 Impact Factor
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    ABSTRACT: The title nitro-phenyl benzamide, C13H9BrN2O3, with two mol-ecules in the asymmetric unit, has dihedral angles of 16.78 (15) and 18.87 (14)° between the benzene rings. An intra-molecular N-H⋯O hydrogen bond is observed in each mol-ecule. In the crystal, the molecules are linked by weak C-H⋯O inter-actions; halogen-halogen inter-actions are also observed [Br⋯Br = 3.4976 (7) Å]. These inter-actions form R (2) 2(10), R (2) 2(15) and R (6) 6(32) edge-fused rings along [010].
    Acta Crystallographica Section E Structure Reports Online 03/2014; 70(Pt 3):o344. · 0.35 Impact Factor
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    ABSTRACT: A detailed mechanistic understanding of the malonoyl peroxide mediated dihydroxylation of alkenes is presented. The reaction is first order in both alkene and peroxide with stoichiometric water playing a dual role. An ionic mechanism is proposed and supported by the use of 18O isotopically labelled peroxide, a radical clock probe and DFT calculations. Hammett analysis suggests the reaction proceeds via a discrete carbocation intermediate which is consistent with the stereochemical outcome of the transformation. A subsequent Woodward-type 1,3-dioxolan-2-yl cation has been trapped in situ and the mechanism of hydrolysis defined by isotopic labelling studies. Stable reaction intermediates have been isolated and characterised by X-ray crystallographic analysis and minor competing reaction pathways identified.
    Chemical Science. 02/2014; 5:1777.
  • Amanda R Buist, Alan R Kennedy, Craig Manzie
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    ABSTRACT: The structures of two anhydrous salt phases of theophylline, namely 1,3-dimethyl-2,6-dioxo-7H-purin-9-ium tetrafluoroborate, C7H9N4O2(+)·BF4(-), and 1,3-dimethyl-2,6-dioxo-7H-purin-9-ium chloride, C7H9N4O2(+)·Cl(-), are reported together with the structures of two monohydrate salt forms, namely 1,3-dimethyl-2,6-dioxo-7H-purin-9-ium chloride monohydrate, C7H9N4O2(+)·Cl(-)·H2O, and 1,3-dimethyl-2,6-dioxo-7H-purin-9-ium bromide monohydrate, C7H9N4O2(+)·Br(-)·H2O. The monohydrate structures are mutually isostructural, with the cations and anions lying on crystallographic mirror planes (Z' = 1/2). The main intermolecular interaction motif is a hydrogen-bonding network in the same mirror plane. The tetrafluoroborate structure is based on planar hydrogen-bonded theopylline cation dimers; the anions interact with the dimers in a pendant fashion. The anhydrous chloride structure has Z' = 2 and in contrast to the other species it does not form planar hydrogen-bonded constructs, instead one-dimensional chains of cations and anions propagate parallel to the crystallographic c direction. An earlier report claiming to describe an anhydrous structure of theophylline hydrochloride is re-examined in light of these results. It is concluded that the earlier structure has been reported in the wrong space group and that it has been chemically misidentified.
    Acta crystallographica. Section C, Structural chemistry. 02/2014; 70(Pt 2):220-4.
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    ABSTRACT: In the title compound, C15H14O2, the terminal rings form a dihedral angle of 52.39 (4)°. The mean plane of the central ester group [r.m.s. deviation = 0.0488 Å] is twisted away from the benzene and phenyl rings by 60.10 (4) and 8.67 (9)°, respectively. In the crystal, mol-ecules are linked by weak C-H⋯O hydrogen bonds, forming C(6) chains which run along [100].
    Acta Crystallographica Section E Structure Reports Online 02/2014; 70(Pt 2):o194. · 0.35 Impact Factor

Publication Stats

1k Citations
1,488.29 Total Impact Points

Institutions

  • 1996–2014
    • University of Strathclyde
      • Department of Pure and Applied Chemistry
      Glasgow, Scotland, United Kingdom
  • 2012–2013
    • Erciyes Üniversitesi
      • Department of Physics
      Kayseri, Kayseri, Turkey
    • Universidad Santiago de Cali
      Santiago de Cali, Valle del Cauca, Colombia
  • 2001–2012
    • Newcastle University
      • School of Chemistry
      Newcastle upon Tyne, ENG, United Kingdom
  • 2011
    • University of Bath
      • Department of Chemistry
      Bath, ENG, United Kingdom
  • 2010
    • Kano University of Science & Technology
      Wudil, Kano, Nigeria
  • 2003–2010
    • Universidad de La Laguna
      • Department of Organic Chemistry
      San Cristóbal de La Laguna, Canary Islands, Spain
  • 2009
    • Spanish National Research Council
      • Instituto de Productos Naturales y Agrobiología
      Madrid, Madrid, Spain
  • 2007–2009
    • Johannes Gutenberg-Universität Mainz
      • Institute of Inorganic and Analytical Chemistry
      Mainz, Rhineland-Palatinate, Germany
  • 2005–2007
    • University of Notre Dame
      • Department of Chemistry and Biochemistry
      United States