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F Atoms (f + atom)
Selected AbstractsStructures and Thermodynamics of the Sulfuranes SF3CN and SF2(CN)2 as well as of the Persulfurane SF4(CN)2 , An ab initio MO Study by the G3(MP2) MethodEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 11 2003Yana Steudel Abstract At the G3(MP2) level of theory the trans isomer 1a of the hypothetical molecule SF4(CN)2 is more stable than the cis isomer 1b by 8 kJ·mol,1. The isomerization of 1a to 1b requires an activation enthalpy of 319 kJ·mol,1 at 298 K. The decomposition of trans -SF4(CN)2 to SF2(CN)2 and F2 is endothermic (,Ho298 = 395 kJ·mol,1) but the elimination of FCN from trans -SF4(CN)2 is exothermic by ,7 kJ·mol,1. The elimination of (CN)2 from cis -SF4(CN)2 is exothermic by ,137 kJ·mol,1. The activation enthalpies for the latter two reactions were calculated as 251 and 311 kJ·mol,1, respectively. Thus, SF4(CN)2 should be a thermally stable compound. In the sulfuranes SF3CN and SF2(CN)2 the CN ligands prefer the equatorial positions; mutual exchange of an axial F atom by an equatorial CN group requires a reaction enthalpy of 51 kJ·mol,1 [SF3CN] or 58 kJ·mol,1 [SF2(CN)2]. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Theoretical studies on the mechanism and kinetics of the reaction of F atom with NCO radicalINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 2 2003Zheng-Yu Zhou The reaction of a F atom with an NCO radical was studied at 6-311+g* level, using DFT methods. All geometries, vibrational frequencies, and energies of different stationary points were calculated by HF, UMP2, and DFT methods, and the results agreed with the experimental values. The vibrational frequencies and vibrational modes of the reactant, intermediates, transition states, and products were calculated and the changes of these frequencies and modes were analyzed. Simultaneously, the vibrational modes of various species were assigned. The relationship and the change among these confirmed the mechanism of the reaction and the process of electron transfer. The major channel for the reaction was found to be the cis-channel. At the same time the rate constant was estimated. A new method of analyzing reaction mechanism is also presented. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 35: 52,60, 2003 [source] When, in the context of drug design, can a fluorine atom successfully substitute a hydroxyl group?INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 4 2002Marcin Hoffmann Abstract In this article, we deal with the question of whether a fluorine atom can substitute a hydroxyl group in such a way that will lead to a compound showing a desired biologic activity, that is, a potential new drug. It is obvious that a fluorine atom differs from a hydroxyl group, as it cannot donate hydrogen bonds. However, it can accept them. Moreover, both fluorine and oxygen are of similar size and are the most electronegative elements. Therefore, a fluorine atom is thought to be a good substitute for a hydroxyl group. However, it was shown that for conformationally labile aliphatic compounds a replacement of a hydroxyl by a fluorine increases conformational diversity, so the fluorine-containing aliphatic molecules are present in equilibrium at room temperature as a mixture of several different conformers. In contrast, for cyclic compounds the substitution of an OH group by an F atom does not much change shape and electrostatic potential around corresponding conformers. Moreover, these compounds are present in equilibrium at room temperature in aqueous solution as a mixture of the same most favored structures. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002 [source] K3TaF8 from laboratory X-ray powder dataACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2010ubomír Smr The crystal structure of tripotassium octafluoridotantalate, K3TaF8, determined from laboratory powder diffraction data by the simulated annealing method and refined by total energy minimization in the solid state, is built from discrete potassium cations, fluoride anions and monocapped trigonal,prismatic [TaF7]2, ions. All six atoms in the asymmetric unit are in special positions of the P63mc space group: the Ta and one F atom in the 2b (3m) sites, the K and two F atoms in the 6c (m) sites, and one F atom in the 2a (3m) site. The structure consists of face-sharing K6 octahedra with a fluoride anion at the center of each octahedron, forming chains of composition [FK3]2+ running along [001] with isolated [TaF7]2, trigonal prisms in between. The structure of the title compound is different from the reported structure of Na3TaF8 and represents a new structure type. [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] Bonding and Bending in Zirconium(IV) and Hafnium(IV) HydrazidesCHEMISTRY - A EUROPEAN JOURNAL, Issue 27 2008Heike Herrmann Dr. Abstract Reaction of the dichloro complexes [M(N2TBSNpy)Cl2] (M=Zr: 1, Hf: 2; TBS: tBuMe2Si; py: pyridine) with one molar equivalent of LiNHNPh2 gave mixtures of the two diastereomeric chlorohydrazido(1,) complexes [M(N2TBSNpy)(NHNPh2)Cl] (M=Zr: 3,a,b, Hf: 4,a,b) in which the diphenylhydrazido(1,) ligand adopts a bent ,1 coordination. This mixture of isomers could be cleanly converted into the deep green diphenylhydrazido(2,) complexes [Zr(N2TBSNpy)(NNPh2)(py)] (5) and [Hf(N2TBSNpy)(NNPh2)(py)] (6), respectively, by dehydrohalogenation with lithium hexamethyldisilazide (LiHMDS) in the presence of one molar equivalent of pyridine. Both complexes contain a linearly coordinated hydrazinediide for which a DFT-based frontier orbital analysis established bonding through one , and two , orbitals. A high polarity of the MN bond was found, in accordance with the description of hydrazinediide(2,) acting as a six-electron donor ligand. The pyridine ligand in [M(N2TBSNpy)(NNPh2)(py)] (M=Zr: 5, Hf: 6) is substitutionally labile as established by line-shape analysis of the dynamic spectra (,G,=19,kcal,mol,1). A change in denticity of the hydrazido unit from ,1 to ,2 was studied by DFT methods. Both forms are calculated to be very close in energy and are only separated by shallow activation barriers, which supports the notion of a rapid ,1 to ,2 interconversion. This process is believed to happen early on in the NN scission in the presence of coupling reagents. Frontier orbital and natural population analyses suggest that a primarily charge-controlled nucleophilic attack at N, is unlikely whereas interaction with an electrophile could play an important role. This hypothesis was tested by the reaction of 5 and 6 with one molar equivalent of B(C6F5)3 to give [Zr(N2TBSNpy)(NNPh2){B(C6F5)3}] (7) and [Hf(N2TBSNpy)(NNPh2){B(C6F5)3}] (8). In these products, B(C6F5)3 becomes attached to the N, atom of the side-on bound hydrazinediide and there is an additional interaction of an ortho -F atom of a C6F5 ring with the metal centre. [source] Nonquenchable Chemical Order,Disorder Phase Transition in Yttrium OxyfluorideEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 1 2005Igor Levin Abstract A chemical order,disorder polymorphic phase transition in yttrium oxyfluoride (YOF) was studied in situ by X-ray and neutron powder diffraction. The high-temperature form of YOF crystallizes with a cubic Fmm fluorite structure in which the O and F atoms are disordered among the tetrahedrally coordinated sites. The low-temperature form of YOF exhibits rhombohedral Rm symmetry and evolves from the high-temperature form by the phase transition associated with the ordering of the O and F atoms. The transition occurs around 560 °C. The superstructure contains layers of [OY4] and [FY4] tetrahedra alternating along the c -axis of the trigonal cell (parallel to the <111> direction of the parent cubic structure). The ordering of the O and F atoms is accompanied by the significant displacements of the Y, O, and F atoms from their ideal positions in the cubic phase. Bond valence sum calculations indicate considerable bond strain for both O and F in the cubic structure; the strain is relieved in the ordered low-temperature phase. The order,disorder transition in YOF is completely reversible and exhibits fast nonquenchable kinetics. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Energy- and Charge-Transfer Processes in a Perylene,BODIPY,Pyridine Tripartite ArrayEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 16 2008Mohammed A. H. Alamiry Abstract A novel boron dipyrromethene (BODIPY) dye has been synthesized in which the F atoms, usually bound to the boron center, have been replaced with 1-ethynylperylene units and a 4-pyridine residue is attached at the meso -position. The perylene units function as photon collectors over the wavelength range from 350 to 480 nm. Despite an unfavorable spectral overlap integral, rapid energy transfer takes place from the singlet-excited state of the perylene unit to the adjacent BODIPY residue, which is itself strongly fluorescent. The mean energy-transfer time is 7,±,2 ps at room temperature. The dominant mechanism for the energy-transfer process is Dexter-type electron exchange, with Förster-type dipole,dipole interactions accounting for less than 10,% of the total transfer probability. There are no indications for light-induced electron transfer in this system, although there is evidence for a nonradiative decay channel not normally seen for F -type BODIPY dyes. This new escape route is further exposed by the application of high pressure. The meso -pyridine group is a passive bystander until protons are added to the system. Then, protonation of the pyridine N atom leads to complete extinction of fluorescence from the BODIPY dye and slight recovery of fluorescence from the perylene units. Quenching of BODIPY-based fluorescence is due to charge-transfer to the pyridinium unit whereas the re-appearance of perylene-based emission is caused by a reduction in the Förster overlap integral upon protonation. Other cations, most notably zinc(II) ions, bind to the pyridine N-atom and induce similar effects but the resultant conjugate is weakly fluorescent.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] The Influence of ZnF2 Doping on the Electrical Properties and Microstructure in Bi2O3,ZnO-Based VaristorsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 1 2010Lihong Cheng ZnO varistors with different amounts of ZnF2 from 0.00 to 0.80 mol% were prepared using a solid-state reaction technique, to explore the potential application of ZnO. The F-doping effects on the microstructure and electrical properties of ZnO-based varistors were investigated. The average grain size of ZnO increased from 4.93 to 6.48 ,m as the ZnF2 content increased. Experimental results showed that as the ZnF2 content increased, the breakdown voltage decreased from 617 to 367 V/mm, and the nonlinear coefficient did not change much. However, a slight increase was observed in the leakage current. Besides, when the ZnF2 content increased, the donor concentration increased from 0.669 × 1018 to 8.720 × 1018 cm,3. The study indicated that ZnF2 played a similar role as sintering aids to promote grain growth and the substitutional F atoms in the bulk served as a donor to increase the donor concentration. [source] Orientational disorder and phase transitions in crystals of dioxofluoromolybdate, (NH4)2MoO2F4ACTA CRYSTALLOGRAPHICA SECTION B, Issue 1 2010Anatoly A. Udovenko Dioxotetrafluoromolybdate, (NH4)2MoO2F4, was synthesized in a single-crystal form and its structures [(I) at 297,K and (II) at 223,K] were determined by X-ray diffraction. Two independent states of a cis -MoO2F4 octahedron are characteristic of static and dynamic disorder in structure (I). The dynamically disordered Mo atom is displaced from the symmetry axis producing four possible orientations of an anion that allow O and F atoms to be identified in separate orientations owing to the inherent differences between the Mo,O and Mo,F bonding. After the phase transition at lower temperature, (I) transforms into the statically disordered structure (II) with three possible orientations of the cis -MoO2F4 octahedron. In this case, it also seemed possible to distinguish between O and F atoms on a local scale. H atoms of two independent NH4 groups in (II) which form bifurcated N,H...F(O) hydrogen bonds were localized. [source] Disorder in crystals of dioxofluorotungstates, (NH4)2WO2F4 and Rb2WO2F4ACTA CRYSTALLOGRAPHICA SECTION B, Issue 6 2008Anatoly A. Udovenko Dioxotetrafluorotungstates (NH4)2WO2F4 [(I) at 297,K and (II) at 133,K] and Rb2WO2F4 (III) were synthesized in a single-crystal form and their structures were determined by X-ray diffraction. Two independent states of the cis -WO2F4 octahedron are characteristic of static and dynamic disorder in structure (I). Dynamically disordered W2 is displaced from the symmetry axis producing four possible orientations of anion that permits O and F atoms to be identified in separate orientations owing to the inherent differences between W,O and W,F bonding. After the phase transition at lower temperature (201,K), (I) transforms into the twin structure (II) with complete O/F ordering. Structure (III) is characterized by full O/F static disorder without any phase transitions at lower temperature. [source] 2-{[(3-Fluorophenyl)amino]methylidene}-3-oxobutanenitrile and 5-{[(3-fluorophenyl)amino]methylidene}-2,2-dimethyl-1,3-dioxane-4,6-dione: X-ray and DFT studiesACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2010Vratislav Langer In the crystal structures of the title compounds, C11H9FN2O, (I), and C13H12FNO4, (II), the molecules are joined pairwise via different hydrogen bonds and the constituent pairs are crosslinked by weak C,H...O hydrogen bonds. The basic structural motif in (I), which is partially disordered, comprises pairs of molecules arranged in an antiparallel fashion which enables C,H...N[triple-bond]C interactions. The pairs of molecules are crosslinked by two weak C,H...O hydrogen bonds. The constituent pair in (II) is formed by intramolecular bifurcated C,H...O/O, and combined inter- and intramolecular N,H...O hydrogen bonds. In both structures, F atoms form weak C,F...H,C interactions with the H atoms of the two neighbouring methyl groups, the H...F separations being 2.59/2.80 and 2.63/2.71,Å in (I) and (II), respectively. The bond orders in the molecules, estimated using the natural bond orbitals (NBO) formalism, correlate with the changes in bond lengths. Deviations from the ideal molecular geometry are explained by the concept of non-equivalent hybrid orbitals. The existence of possible conformers of (I) and (II) is analysed by molecular calculations at the B3LYP/6,31+G** level of theory. [source] Intermolecular ,-stacking and F...F interactions of fluorine-substituted meso -alkynylporphyrinACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2010Yuta Marushima Two C2-symmetric meso -alkynylporphyrins, namely 5,15-bis[(4-butyl-2,3,5,6-tetrafluorophenyl)ethynyl]-10,20-dipropylporphyrin, C50H42F8N4, (I), and 5,15-bis[(4-butylphenyl)ethynyl]-10,20-dipropylporphyrin, C50H50N4, (II), show remarkable ,,, stacking that forms columns of porphyrin centers. The tetrafluorophenylene moieties in (I) show intermolecular interactions with each other through the F atoms, forming one-dimensional ribbons. No significant ,,, interactions are observed in the plane of the phenylene and tetrafluorophenylene moieties in either (I) or (II). The molecules of both compounds lie about inversion centers. [source] The twinned crystal structure of tripotassium benzene-1,3,5-tris(trifluoroborate)ACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2010Daniel Franz The title compound, 3K+·C6H3B3F93,, crystallizes as discrete anions and cations which are connected by K...F and K..., interactions. Two of the ,BF3 residues attached to the aromatic ring adopt a conformation with all F atoms out of the plane of the aromatic ring, whereas the third residue has an almost synperiplanar conformation for one of the F,B,C,C torsion angles. It is remarkable that only one of the K+ cations interacts with the arene ring and that only one side of the aromatic ring coordinates to a K+ cation. As a result, a sandwich structure does not occur. All K+ ions show a coordination mode that cannot be conveniently described with a polyhedron. The anions are located in the (102) planes with the K+ cations located between these planes. The investigated crystal was a nonmerohedral twin with the fractional contribution of the minor twin component being 0.405,(4). The title compound is the first example of a structure containing a benzene ring substituted with three ,BF3 groups. Only eight other structures have been reported in which a benzene ring carries at least one ,BF3 group. Just five of these contain a K+ ion, but in none of these is the K+ ion coordinated to the aromatic ring. [source] A new chain structure: catena -poly[4,4,-(ethane-1,2-diyl)dipyridinium bis[[aquadifluoridooxidovanadate]-,-fluorido]]ACTA CRYSTALLOGRAPHICA SECTION C, Issue 5 2010David W. Aldous The title compound, {(C12H12N2)[V2F6O2(H2O)2]}n, features a novel extended-chain moiety, [VOF2F2/2(H2O)]n, comprising trans vertex-connected VOF4(H2O) octahedra. The octahedra themselves show the characteristic distortion due to the off-centring of the V4+ ion, such that a short terminal V=O bond and an elongated trans V,OH2 bond are present. Hydrogen bonding from the water molecules to terminal F atoms in adjacent chains generates associated chain dimers, which are loosely linked into sheets via additional hydrogen bonding involving the organic moieties. Structural relationships with previously described vanadium oxyfluoride species are briefly discussed. [source] K3TaF8 from laboratory X-ray powder dataACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2010ubomír Smr The crystal structure of tripotassium octafluoridotantalate, K3TaF8, determined from laboratory powder diffraction data by the simulated annealing method and refined by total energy minimization in the solid state, is built from discrete potassium cations, fluoride anions and monocapped trigonal,prismatic [TaF7]2, ions. All six atoms in the asymmetric unit are in special positions of the P63mc space group: the Ta and one F atom in the 2b (3m) sites, the K and two F atoms in the 6c (m) sites, and one F atom in the 2a (3m) site. The structure consists of face-sharing K6 octahedra with a fluoride anion at the center of each octahedron, forming chains of composition [FK3]2+ running along [001] with isolated [TaF7]2, trigonal prisms in between. The structure of the title compound is different from the reported structure of Na3TaF8 and represents a new structure type. [source] Sodium iodine(V) oxyfluoride, NaIO2F2ACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2008Jean-Paul Laval As an extension of a general structural study concerning fluorides and oxyfluorides of cations presenting a stereochemically active electronic lone pair, until now limited to tellurium(IV) phases, the previously unknown structure of NaIO2F2 corresponds to a new structure type based on isolated IO2F2, polyhedra forming sheets separated by Na+ layers. The sodium ion is octahedrally coordinated with 2/m site symmetry, while the IV atom has m2m symmetry with a stereochemically active lone electron pair. The O and F atoms (both with m symmetry) are bonded to the IV atoms in a fully ordered manner. A comparison with the structure of ferroelastic KIO2F2 and with structures based on hexagonal close packing of anions, mainly rutile-type and FeTeO3F-type, reveals differences that are attributed to the smaller ionic radius of Na+ and the ordering of the Na and I cations. [source] Three hexafluoridoiridates(IV), Ca[IrF6]·2H2O, Sr[IrF6]·2H2O and Ba[IrF6]ACTA CRYSTALLOGRAPHICA SECTION C, Issue 11 2007Anton I. Smolentsev The structures of the hexafluoridoiridates(IV) of calcium, Ca[IrF6]·2H2O [calcium hexafluoridoiridate(IV) dihydrate], strontium, Sr[IrF6]·2H2O [strontium hexafluoridoiridate(IV) dihydrate], and barium, Ba[IrF6] [barium hexafluoridoiridate(IV)], have been determined by single-crystal X-ray analysis. The first two compounds are isomorphous. Their metal cations are eight-coordinated in a distorted square-antiprismatic coordination environment, and their anions are represented by an almost ideal octahedron. These two structures can be described as frameworks in which all atoms occupy general positions. Sr[RhF6] and Ba[RhF6] have a different space group (, from powder diffraction data) but similar cell dimensions. The structures are very close to that of Ba[IrF6]. The cation is in a cuboctahedral coordination. The metal atoms are located on special positions of symmetry, while the F atoms are in general positions. [source] Strontium tetrafluoridoborate and barium tetrafluoridoborateACTA CRYSTALLOGRAPHICA SECTION C, Issue 9 2007Tina Buni In Sr(BF4)2, which is isomorphous with the previously published Ca(BF4)2, the metal atom possesses a coordination number of 8 with a square-antiprismatic environment. Each tetrafluoridoborate anion is bonded to four metal centers. In the barium derivative, the metal center, with symmetry 2/m, is surrounded by 14 F atoms. The B atom and two of the three independent F atoms occupy special positions with symmetry m. Each anion is connected to five Ba atoms. This structure differs significantly from an earlier published structure of Ba(BF4)2 [published as Ba2(BF4)4; Lin, Cheng, Chen & Huang (1998). Jiegon Huaxue, 17, 245]. The radial distribution functions for the present Ba(BF4)2 and earlier Ba2(BF4)4 structures differ significantly. [source] (Pyrazole)silver(I) and -gold(I) Complexes with Strong and Weak Hydrogen-Bonding Interactions as the Basis of One- or Two-Dimensional StructuresEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 15 2004M. Luz Gallego Abstract New AuI/AgI complexes containing one or two substituted pyrazole ligands [Au(Hpzbp2)(PPh3)](p -CH3C6H4SO3) [Hpzbp2 = 3,5-bis(4- n -butoxyphenyl)pyrazole] (1) and [M(HpzR2)2]nX [HpzR2 = Hpzbp2, M = Au, n = 1, X = p -CH3C6H4SO3 (2), NO3, (3); n = 2, X = 1,5-naphthalenedisulfonate (1,5nds) (4); HpzR2 = Hpzbp2, M = Ag, n = 1, X = BF4, (5), CF3SO3, (6); HpzR2 = HpzNO2 (3,5-dimethyl-4-nitropyrazole), M = Ag, n = 1, X = BF4, (7), CF3SO3, (8)], have been prepared and characterized. Compounds 1, 2, 5 and 8 have been proved to be useful for supramolecular assembly from their single X-ray diffraction analysis. In all cases strong hydrogen bonds maintain the cationic units bonded to their corresponding counterions. The crystal packing arrangement of 1, 2 and 5 is, however, determined by weak C,H···O/F hydrogen-bonding interactions involving the remaining O/F atoms of the counterion. By contrast, for 8 a two-dimensional layer-type polymeric network is formed by ,···, (NO2···NO2) and coordinative Ag···O interactions in which the NO2 substituent on the pyrazole is implicated. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] | ||||||||||