bluuebunny/crossref_metadata_2025_split huggingface dataset:
Die Koordinationszahl von Lanthaniden: Thermodynamik der LnIIIEDTA‐Mischkomplexe mit den Anionen der 8‐Hydroxychinolin‐5‐sulfonsäure, Iminodiessigsäure und Nitrilotriessigsäure
Authors: Geier G. , Karlen U. 
Published: December 2004

AbstractThe values of ΔG, ΔH and ΔS for the formation of the mixed 1:1:1 lanthanide EDTA complexes with the anions of 8‐hydroxyquinoline‐5‐sulfonic acid, iminodiacetic acid and nitrilotriacetic acid were determined by pH‐titrations and a direct calorimetric method. These thermodynamic data are discussed and compared with those for the formation of the Ln(III)EDTA complexes. Contrary to current opinion it is concluded that all trivalent lanthanide aquoions have the same coordination number in dilute solution. However, in the series of the lanthanide EDTA complexes the coordination number changes between Sm and Tb. In this region, equilibria occur between two types of EDTA complexes with different numbers of coordinated water molecules:

equation image
The corresponding equilibrium constants could be evaluated. The coordination number changes also in many other Ln complexes along the lanthanide series, and similar equilibria occur.
Pyrolysen‐ und Hydrierungsversuche in der Elemol‐ und Dihydrogeijeren‐Reihe
Authors: Ganter C. , Keller‐Wojtkiewicz Frau B. 
Published: December 2004

Abstract
The pyrolysis of elemol (1) in the presence of benzoic or p‐nitrobenzoic acid, and of elemyl‐p‐nitrobenzoate (3) was studied. From the many products formed, the compounds 6, 7, 8, 10, 11, 14, 15 and 18 were isolated and identified. On the basis of systematic experiments in the elemol (1) and dihydrogeijerene (26) series the sequence of the formation of these products could be determined. Several factors influencing the compositions of the pyrolysis mixtures are discussed.
The products of pyrolysis of both series [elemol (1) and dihydrogeijerene (26), respectively] were catalytically hydrogenated, yielding the saturated hydrocarbons 34, 35–37, and 38–40, respectively.
The synthesis of racemic dihydrogeijerene (26) was achieved starting from germacrone (41).
Beiträge zur Chemie des 4,5‐Dihydro‐10H‐benzo [5, 6]cyclohepta[1,2‐b]thiophens
Authors: Bastian J. M. , Ebnöther A. , Jucker E. , Rissi E. , Stoll A. P. 
Published: December 2004

AbstractSeveral syntheses of 4,5‐dihydro‐10 H‐benzo[5,6]‐cyclohepta[1, 2‐b]thiophen‐10‐one (I b) are described. The pharmacological properties of the compounds XIII, which derive from IB through basic substitution on position 10, are briefly mentioned.
Über den Verteilungssatz der Auxochrome bei Azokörpern, III Azokörper mit zueinander p‐ständigen Auxochromen
Authors: Kokkinos K. , Wizinger R. 
Published: December 2004

AbstractIt is shown with some derivatives of 2‐hydroxy‐azobenzene and 2‐hydroxy‐4 nitro‐azobenzene that — in conformity with the rule of repartition — auxochromes in p‐position have a strong bathochromic effect.
Base‐Catalysed H‐D Exchange in 1 ‐Methylthiolanium Iodide
Authors: Barbarella G. , Garbesi A. , Fava A. 
Published: December 2004

AbstractThe kinetics of the base‐catalysed H/D exchange of the 1‐methylthiolanium cation in heavy water has been studied. Of the four α‐methylene protons, two exchange much faster than the other two, a result which requires that reprotonation of the carbanion intermediate occurs with retention of configuration. NMR. spectral analysis indicates that the protons undergoing faster exchange bear a trans relation to the lone‐pair on sulfur. This conclusion appears to conform to Wolfe's theory on the stability of carbanions [3].
Rapid Syntheses of Hexa and Heptahelicene
Authors: Martin R. H. , Marchant Marie‐Jeanne , Baes M. 
Published: December 2004

AbstractA two‐step synthesis of hexahelicene (scheme 1; 53% over‐all yield), a three‐step synthesis of hexaheliene (scheme 2; 33% over‐all yield), and a two‐step synthesis of heptahelicene (scheme 3; 14% over‐all yield) are described.
Cystinpeptide aus (S‐Acetamidomethyl‐cystein)‐peptiden durch Oxydation mit Jod: Die synthese von cyclo‐L‐cystin
Authors: Kamber B. 
Published: December 2004

AbstractThe conversion of S‐acetamidomethyl cysteine peptides to by a reaction with iodine is described. The method is applied in the synthesis of the hitherto unknown cyclo‐L‐cystine. The structure of this compound was confirmed by molecular weight determination, NMR. and mass spectroscopy.
Harmoniques des vibrations de valence CH dans les alcanes et les halogénures de t‐butyle
Authors: Avanessoff M. , Gäumann T. 
Published: December 2004

AbstractThe first and second harmonic CH and CD valence vibrations of alkanes and t‐butyl halides have been measured. A model is proposed for the methyl and methylene groups, which allows the calculation of the anharmonicity constants of every vibrational mode and of the couplings between the modes. The already known large values (−100 to −150 cm−1) for the anharmonicity constants that couple the symmetrical with the asymmetrical modes are confirmed. As compared with lower harmonics combination bands become predominant for the higher ones; they allow the application of a diatomic model to estimate higher harmonics and the energy of dissociation.
Etude de composés d'addition d'acides de Lewis, XXXIV [1] Composés d'addition de benzoquinone‐1, 4 avec TiCl4
Authors: Giallonardo R. , Susz Bernard‐P. 
Published: December 2004

AbstractThe adduct 1,4‐benzoquine · TiCl4 has been prepared in CH2Cl2 solution at about −60°. Its IR. spectrum has been recorded at the same temperature. The experimental study of the vibrational frequencies has been completed by the calculation of the fundamental vibrations in the molecular plane, using Wilson's FG method, with slightly simplified models of 1,4‐benzoquinone · TiCl4 (13 masses) and 1,4‐benzoquinone · 2 TiCl4 (14 masses); analysis by use of internal and symmetry coordinates. An assignment of most of the observed bands is proposed and the conclusion is reached that the complex, when solid, is (1,4‐benzoquinone · TiCl4)n.The force constants F(CO) are 9,85 · 105 dyne/cm for the quinone and 8,8 · 105 dyne/cm for the disturbed carbonyl bond of the polymerized complex in the model proposed.At ordinary temperature in benzene solution of the components the adduct 1,4‐benzoquinone. TiCl4 · benzene precipitated; with the help of the models, the fundamental vibrations of its IR. spectrum have been assigned.
Microcalorimetric Measurements with the Valinomycin ‐ Potassium Iodide Complex. Preliminary communication
Authors: Möschler Hans Jörg , Weder Hans‐Georg , Schwyzer Robert 
Published: December 2004

AbstractDie Mikrokalorimetrie wurde erstmals zur Bestimmung von Assoziationskonstante, Reaktionsenthalpie, freier Reaktionsenergie und Reaktionsentropie der Komplexbildung zwischen Kaliumjodid und Valinomycin in Äthanol verwendet. Eine konstante Konzentration von Valinomycin (10−4M) wurde mit verschiedenen Konzentrationen von Kaliumjodid (10−5 bis 10−3M) versetzt. Die Enthalpieänderung (Grössenordnung 0,5 bis 5,0 mcal) wurde als Titrationsparameter benützt. Die Auswertung der Sättigungskurve nach Klopfenstein [3] ergab.
Note on the rôle of cyanides and polyphosphates in the formation of peptides in aqueous solutions of amino acids, at room temperature, as a possible prebiotic process
Authors: Rabinowitz Joseph 
Published: December 2004

AbstractLes cyanures et les polyphosphates jouent un rôle important dans l'évolution chimique. Des solutions aqueuses d'acides aminés additionnées de trimétaphosphate et de cyanure, amenées à pH 11,5–12 par NH3 et maintenues à ce pH 4 jours à température ordinaire, contiennent les dipeptides correspondants, formés avec des rendements à peu près doubles de ceux obtenus en présence du seul trimétaphosphate. En présence uniquement de cyanure, il ne se forme pas de peptides. Dans ces mêmes conditions, une solution de cyanure ne fournit ni acides aminés ni peptides. Pour la formation abiotique de peptides à partir d'amino‐acides, le système polyphosphate‐cyanure est dono plus efficace que chacun de ses composants individuellement.
Détermination de constantes de formation des complexes phosphorescents du bore avec la benzoylacétone, à l'aide de durées de vie moyenne d'émission
Authors: Gamba G. , Marcantonatos M. 
Published: December 2004

AbstractA method, based on mean life times (τ) of T → S emission, is proposed for the determination of stability constants of two successive mononuclear complexes and is applied to the boric acid‐benzoylacetone AB et AB2 phosphorescent complexes in glassy (77 K) ether‐concentrated sulfuric acid media. Results show that this method ‐ if not limited by very near τ values of the complexes – is precise and applicable even to cases where, at high ligand concentrations, filter effects intervene. The use of τ values by this procedure offers, over colorimetric and fluorometric methods, enhanced possibilities to determine the type of complexes formed and their stability.
Photochemical Reactions. Part 64 [1]. The photochemistry of 3‐alkyl‐cyclopent‐2‐en‐ones
Authors: Reinfried R. , Belluš D. , Schaffner K. 
Published: December 2004

AbstractOn ultraviolet irradiation in toluene, cyclopent‐2‐en‐one (1a) and 3‐methylcyclopent‐2‐en‐one (1b) undergo dimerisation (→ 3a, b, 4b), whereas 3‐t‐butyl‐cyclopent‐2‐en‐one (1e) and the bicyclo [3.2.1]octenone 2a only react with the solvent (→ 5e–7e, 8–10). The 3‐ethyl‐(1c) and 3‐isopropyl‐cyclopent‐2‐en‐ones (1d) afford by dimerisation products 3c, d, 4c and by reaction with the solvent 5c, d, 6c, d, 7d. The β‐methoxy‐enones 1f and 2b are unreactive under comparable irradiation conditions. The head‐to‐head cyclobutane dimer 3b (HH) by separate irradiation at < 3400 Å in toluene, is reconverted to 1b. By similar irradiation each of the head‐to‐tail dimers 3b (anti‐ and syn‐HT) and also the unsaturated dimer 4b give a new isomer of unknown structure besides small amounts of monomer 1b and relatively large amounts of insoluble material.The photoreactions of 1b‐e can be quenched by naphthalene. Stern‐Volmer plots for the quenching of the dimers of 1b, 1c, and 1d, and of 3‐t‐butylcyclopentanone (5e) and the dihydro dimer 7e are linear and within each experiment, the slopes satisfactorily coincide, whereas the slope for the α‐benzyl ketone 6c is distinctly greater than that for the dimers 3c. A similar differentiation, although less pronounced, is found between the benzyl ketones 6d and 6e and the respective accompanying products.
Synthesis and Absolute Configuration of Cryptostylines I, II, and III
Authors: Brossi A. , Teitel S. 
Published: December 2004

AbstractDie Darstellung der drei optisch aktiven natürlichen Alkaloide Cryptostyline I, II und III aus Cryptostylis fulva Schltr. und ihrer drei unnatürlichen Antipoden wird beschrieben. Es wird gezeigt, dass die drei natürlichen Cryptostyline S‐Konfiguration besitzen. Die berichtete leichte Racemisierbarkeit der natürlichen Cryptostyline wird auf optische Unreinheit der ursprünglichen Präparate zurückgeführt.
Pyrrolidide als Derivate für die Strukturaufklärung aliphatischer und alicyclischer Carbonsäuren mittels Massenspektrometrie
Authors: Vetter W. , Walther W. , Vecchi M. 
Published: December 2004

AbstractThe pyrrolidide group is, in contrast to the carboxy‐ and ester groups, capable of inducing strong electron impact fragmentation at the b̃‐ and γ‐bonds in complicated alicyclic and aliphatic compounds. The fragments so formed allow certain conclusions concerning the structure in the neighbourhood of the functional group.
Evidence for a synfacial nucleophilic displacement with allylic rearrangement. Mechanistic conclusions. Preliminary communication
Authors: Jefford C. W. , Sweeney A. , Hill D. T. , Delay F. 
Published: December 2004

AbstractReduction of exo‐2‐methyl‐3, 4‐dichlorobicyclo[3.2.1]oct‐2‐ene and the exo‐2‐phenyl‐3,4‐dibromo analogue with lithium aluminium hydride proceeds mainly with allylic rearrangement. Moreover, hydride enters and bromide leaves synfacially. The stereochemistry of the process is discussed in the light of the favourable energy of a quasi‐cyclic transition state in which reagent and halide are complexed.
Hydroxyalkylation d'hydantoínes monocycliques au moyen de composés époxydés
Authors: Porret D. , Habermeier J. 
Published: December 2004

AbstractPar réaction entre hydantoines monocycliques et substances monoépoxydées comme l'oxyde d'éthylène dans des rapports moléculaires et des conditions appropriées, on obtient des produits hydroxyalkylés définis: les (hydroxy‐2‐alkyl)‐3‐hydantoïnes, bis‐(hydroxy‐2‐alkyl)‐1,3‐hydantoïnes et bis‐(hydroxyalkyl‐polyoxyalkyl)‐1,3‐hydantoïnes, quie sont des produits intermédiaires intéressants. Leur préparation et quelques‐unes de leurs propriétés sont étudiées.
Synthetic Studies on Damascenones
Authors: Büchi G. , Wüest H. 
Published: December 2004

AbstractThe odor principle β‐damascenone and its isomer α‐damascenone have been prepared by treatment of the corresponding ethyl safranates with excess allyl lithium followed by alkoxide catalyzed isomerization of the resulting products with β, γ‐unsaturated ketonic side chains. Addition of allyltriphenylphosphorane (preferably prepared from allyltriphenylphosphonium chloride) rather than the propenyl isomer to ethyl α‐isopropylidene‐acetoacetate produced ethyl α‐safranate. This represents a new, potentially general method for the synthesis of functionalized cyclohexadienes.
Die Struktur von Corchorosid B. Glycoside und Aglykone, 329. Mitteilung
Authors: Venkata Rao E. , Venkata Rao D. , Pavanaram S. K. , Von Euw J. , Reichstein T. 
Published: December 2004

AbstractCorchoroside B has the empirical formula C29H42O8 and was found to be a L‐rhammoside of canarigenin (5), most probably the α, L‐rhamnopyranoside (1).
Indolo[3,3a,4‐gh]chinoline und 10a, 6a‐Iminopropanoindolo[3,3a,4‐gh] chinoline. Stereospezifische Synthesen und Umlagerungen. Teil I. 8. Mitteilung über synthetische Indolverbindungen
Authors: Stoll Andréea P. , Niklaus P. , Troxler F. 
Published: December 2004

AbstractThe stereospecific cyclization of derivatives of 1‐benzyl‐5‐oxo‐1,3,4,5‐tetrahydrobenzo[cd]indole to trans‐octahydroindolo[3,3a,4‐gh]quinolines 3 and 4 is described. The trans methyl esters (4b and 4c) were converted with BF3/CH3OH to the thermodynamically more stable cis‐epimers 5. The structures and stereochemistry of the products, deduced from chemical evidence and analysis of models, are compatible with the NMR. data.
Herstellung von ar‐Pentafluor‐L‐phenylalanin
Authors: Fauchère Jean‐Luc , Schwyzer Robert 
Published: December 2004

AbstractAn enzymatic resolution of ar‐pentafluoro‐DL‐phenylalanine is described. The L antipode has been isolated and its Nα‐t‐butoxycarbonyl derivative prepared.
The Electrocyclic Cyclopropyl‐Allyl Rearrangement. Preliminary communication
Authors: Haselbach E. 
Published: December 2004

AbstractMINDO‐2 SCF calculations indicate that ring‐opening of cyclopropyl radical (I) to allyl radical (II) is more favourable via a disrotatory reaction path, the calculated activation energy being ∼30 kcal/mole. (For conrotatory opening the activation energy was found to be ∼44 kcal/mole.) The two critical motions of the nuclei during the transformation are found to be strongly decoupled, i.e. rupture of the CH2βCH2 bond precedes rotation of the CH2 groups. As predicted by qualitative theories both ring‐opening modes are unfavourable since they involve a change in electronic ground‐state symmetry between I and II. The preferred ring‐opening mode is discussed qualitatively in terms of Evans' principle.
The Interaction of Non‐bonding Orbitals in Dicarbonyls: Ab Initio Results on Glyoxal
Authors: Ha T.‐K. , Hug W. 
Published: December 2004

AbstractDie energetische Lage der kanonischen Molekelorbitale von Glyoxal in der trans‐ und cis‐Konformation wurde durch ab initio‐Rechnungen bestimmt. Die Wechselwirkung der < nichtibindenden > Orbitale dieser Molekel wird diskutiert.
De la chimie des ptérines, 37e communication Mécanisme d'oxydation des tétrahydroptérines disubstituées en C(6) et localisation de l'électron célibataire chez les radicaux qui en découlent
Authors: Viscontini M. , Argentini M. 
Published: December 2004

Abstract14C a été incorporé dans le groupe méthylène de la chaîne latérale de l'aminométhyl‐6‐méthyl‐6‐tétrahydro‐5,6,7,8‐ptérine. Oxydée à l'air dans des conditions physiologiques, cette substance fournit de l'aldéhyde formique et de la méthyl‐6‐ptérine radioactifs, dus respectivement à und dégradation de la chaîne latérale et à une ouverture du cycle tétrahydropyrazinique suivie de recyclisation. Cette observation est discutée au point de vue tant chimique que biologique.
Über Pterinchemie. 38. Mitteilung. Neue Synthesen von Folsäureanalogen
Authors: Viscontini M. , Bieri J. 
Published: December 2004

AbstractEine einfache Synthese des 6‐Formylpterins aus Neopterin wird beschrieben. Dieses isomerenfrei erhaltene Produkt wird als Edukt für die Herstellung von sehr reinen, isomerenfreinen Folsäureanalogen verwendet. Das 6‐Formylpterin wird mit p‐Aminoaryl‐Derivaten zu 6‐Azomethin‐pterinen kondensiert. Die CH  N‐Gruppierung lässt sich dann mit NaBH4 sehr leicht unter Bildung der entsprechenden Amino‐methyl‐pterinen reduzieren.
Komplexe mit makrocyclischen Liganden, II. Zweischrittmechanismus bei der Komplexbildung von Cu2+ mit meso‐5,7,7,12,14,14‐Hexamethyl‐1,4,8,11‐tetraazacyclotetradecan
Authors: Kaden Th. A. 
Published: December 2004

AbstractThe complex formation between CuII and the title compound (tet a) is studied by spectrophotometry and pH‐stat techniques. Between pH 4 and 5,5 the reaction proceeds in two steps, the first giving a blue intermediate, Cu(teta)2+ (blue), exhibiting a broad absorption band at 620 nm. Titration with NaOH and the absorption spectrum suggest that, in the intermediate, CuII is coordinated to only two amino groups of the ligand. Both steps are slow compared to other complex formation reactions of CuII. The rate of the first step, in which Cu(tet a)2+ (blue) is formed, is given by v1 = k1 · [Cu2+] [(tet a) H]/[H+] with k1 = 2,7 · 10−6 s−1 at 40° and I = 0,1. In the second step the last two nitrogens of the quadridentate ligand are bound to CuII, giving the mauve end product. The rate of this step is given by v2 = k2 · [Cu(tet a)OH+ (blue)] [OH−] with k2 = 1,2 · 103 M−1 s−1 at 50° and I = 0,5.
Die Dienol‐Benzol‐Umlagerung von Propargylcyclohexadienolen: aromatische [1,2]‐, [3,3]‐ und [3,4]‐sigmatropische Umlagerungen
Authors: Heimgartner H. , Zsindely J. , Hansen H.‐J. , Schmid H. 
Published: December 2004

AbstractThe acid catalysed dienol‐benzene rearrangement of methyl substituted o‐ and p‐propargylcyclohexadienols (18–22, 34 and 35) was investigated. In the first step water is eliminated to yield the corresponding methyl propargyl benzonium ions (cf. scheme 6, a), which undergo [1s, 2s] sigmatropic rearrangements to give propargylbenzenes (28, 29, 30, 38) and [3s, 4s] sigmatropic rearrangements to give allenylbenzenes (24–27, 40) (cf. schemes 2, 3, 5, 6). [3s, 3s] sigmatropic rearrangements occur only to a small extend. In the rearrangement of 2‐propargyl‐2,4,6‐trimethylcyclohexa‐3,5‐dien‐1‐ol (18) a [1s, 2s] sigmatropic methyl shift is observed (4%).
Beitrüge zur Chemie der Si‐N‐Bindung, XXII N,N′‐Tetrakis(trimethylsilyl)methylendiamin
Authors: Fink Walter 
Published: December 2004

AbstractN.N′‐Tetrakis‐Tetrakis(trimethylsilyl)methylenediamine is prepared by the reaction of lithium‐bis(trimethylsilyl)amide with tris(chloromethyl)amine.
Über die Synthese von in 1‐Stellung substituierten 4‐Nitro‐acridonen
Authors: Burdeska K. , Pugin A. 
Published: December 2004

AbstractDiphenylaminecarboxylic acids can be prepared in high yields by reacting 1‐chloro‐3,4‐dinitrobenzene with anthranilic acids. The acridones obtained by ring closure of these diphenylaminecarboxylic acids represent valuable starting materials for the synthesis of disperse dyes and pigments.
Synthese von [2,7‐Cystin]‐Gramicidin S, einem künstlichen homodet‐heterodet‐bicyclischen Decapeptid
Authors: Ludescher Urs , Schwyzer Robert 
Published: December 2004

AbstractThe first synthesis of a homodetic‐heterodetic‐bicyclic polypeptide, [2,7‐cystine]‐gramicidin S, is described. For the protection of the C‐terminal carboxyl and the cysteine sulfhydryl functions, the 2‐(toluene‐p‐sulfonyl)‐ethyl‐ (Tsa) and the acetamidomethyl‐ (Acm) groups, respectively, were used. Stepwise synthesis from the C‐terminus, using Nα Boc‐amino acids, and selective removal of protecting groups yielded the two pentapeptide derivatives: Boc · Val‐Cys‐(Acm)‐Lem)‐Leu‐phe‐Pro · OH and H · Val‐Cys(Acm)‐Leu‐phe‐Pro · OTsa. They were condensed with dicyclohexyl‐carbodiimide and 1‐hydroxybenzotriazole to give the crystalline decapeptide Boc · [Val‐Cys(Acm)‐Leu‐phe‐Pro]2 · OTsa. Removal of the Tsa group by β‐elimination at pH 11.5 yielded the crystalline free acid, which was further converted (by treatment with di‐p‐nitrophenyl sulfite followed by TFA) to TFA, H · [Val‐Cys(Acm)‐Leu‐phe‐Pro]2 · ONp. Cyclization of the active ester in warm pyridine gave a mixture of (2,7‐bis‐S‐acetamidomethyl‐cysteine]‐gramicidin S (27% yield) and (2,7‐cysteine)‐gramicidin S (4%). The former compound was readily converted to the latter by treatment with I2 in MeOH. In the bicyclic peptide, the decapeptide ring is contained in a β‐type secondary structure, identical with that in gramicidin S; the disulfide bridge shows P‐helical chirality and gives rise to a negative Cotton effect at 271 nm [3].
Dérivés C‐glycosyliques VIII. Synthèse de C‐glycosyl‐3‐pyrazoles à partir d'une nitrilimine dérivée de l'anhydro‐2,5‐D‐ribose. Compétition entre cyclo‐additions dipolaires‐1,3 et cyclisations non concertés
Authors: Tronchet J. M. J. , Perret Melle F. 
Published: December 2004

AbstractSeveral 3‐(2,5‐anhydro‐ribosyl)‐pyrazoles of potential medicinal interest have been synthesized by reacting alkynes or alkynylmagnesium bromides with the p‐nitrophenylhydrazone of 2,5‐anhydro‐ribonyl bromide. From a mechanistic standpoint, it has been shown that the sugar‐nitrilimine used in these studies reacts more readily as an electrophile than as a dipole. Thus, the hydrazonyl bromide gave exclusively the corresponding phenylethynylhydrazone when treated with phenylethynylmagnesium bromide and led to a 1:1 mixture of phenylethynylhydrazone and pyrazole when reacted with phenylacetylene. This proves that nucleophilic additions onto nitrilimines are much faster than Huisgen's 1,3‐dipolar cycloadditions.
Kinetic Salt Effect in the 18O‐Exchange Reaction between Bromate and Water
Authors: Gamsjäger H. , Baertschi P. 
Published: December 2004

AbstractThe kinetic salt effect in the 18O‐exchange reaction between bromate ion and water has been investigated at 60° in a range of ionic strength from 0.02M < I < 1.9M using NaNO3 or NaClO4 as inert salts. From the experimental data the following relation was deduced for the uncatalysed reaction path

In the H+‐catalysed reaction path the Brønsted‐Davies equation was obeyed up to I ⋍ 0.1M

At I > 0.8M the sign of Δ logk2/Δ I1/2 was positive. The theoretical interpretation of these results is consistent with the mechanistic evidence obtained previously from the rate law and the solvent isotope effects.
The Crystal and Molecular Structure of 3,5,7‐Triphenyl‐4H‐1,2‐Diazepine Picrate
Authors: Gerdil R. 
Published: December 2004

AbstractThe crystal structure of 3,5,7‐triphenyl‐4H‐1,2‐diazepine (monoclinic, a = 8.132, b = 13.180, c = 24.204 Å, β = 104.15°, space group P21/c. Z = 4) has been determined by X‐ray analysis. The 1,2‐diazepine ring adopts a boat conformation with a methylene group at the prow. The phenoxide group of the picrate moiety is bonded to one of the diazepine nitrogen atoms through an hydrogen bond.
Untersuchung über die Verteilung von Substanzen in Dünnschichtchromatogrammen
Authors: Seiler H. 
Published: December 2004

AbstractDensitometric techniques are common for the in situ quantitative investigations of thin‐layer chromatograms. The present paper concernes investigations of the distribution of substances within their spots by the aid of radio‐isotopes. The distribution depends on the kind of adsorption mechanisms.