bluuebunny/crossref_metadata_2025_split huggingface dataset:
Le Spectre de Masse du Cyclopentanol et du 2d2, 5d2‐Cyclopentanol
Authors: Natalis P. 
Published: September 2010

AbstractBy the study of 2d2, 5d2‐cyclopentanol mass spectra recorded with variable energy electrons from 12 to 70 volts, it is possible to explain the behaviour of non‐labelled cyclopentanol under electron impact.An interpretation of the ring opening and breaking processes for ionized molecules can be given by determining the composition and to some extent the structure of fragment ions and by studying the metastable transitions. The molecular ions have mainly the structure (CHOH–CH2–CH2–CH2–CH2)+. The rearrangement ions OH2+, OH3+, CHOH2+ common to alcohols have been found. Some conclusions are in agreement with previous results obtained with cyclopentanone, methylcyclopentane and cyclopentyl bromide, in particular the fragility of the α(C–C) bond.
Spectrophotométrie Infra‐Rouge des Produits de Réaction de L'Isocyanate de Vinyle Avec Les Amines
Authors: Moelants L. J. , Hart R. 
Published: September 2010

AbstractPax réaction de l'isocyanate de vinyle avec les dérivés aminés, on obtient des produits pour lesquels deux structures tautomères sont possibles: soit du type N‐vinylurée (I), soit du type N‐éthylidène‐urée (II).L'étude spectrophotométrique infra‐rouge permet d'attribuer à ces produits la structure I.
Studies on halogenated aliphatic compounds. V. The halogenated acetonitriles under electron impact
Authors: van Der Kelen G. P. , De Bièvre P. J. 
Published: September 2010

AbstractLes spectres de masse de CH3CN, CH2FCN et CH2ClCN ont été étudiés à des potentiels d'accélération des électrons décroissants de 70 V jusqu'au potentiel d'ionisation des molécules. Les spectres de masse de CHCl2CN, CHF2CN, CCl3CN et CF3CN ont été examinés à 70 V et à 25 V. L'allure des courbes d'abondance des différents fragments ioniques en fonction de l'énergie des électrons et l'étude de l'abondance relative de ces fragments, conduisent à l'établissement d'un schéma de décomposition de ces molécules sous l'impact électronique. Pour les trois composés CH3CN, CH2FCN, CH2ClCN on observe que le nombre d'ions formés par des processus indirects augmente linéairement en fonction de la valeur de l'électronégativité suivant Pauling des atomes H, Cl et F.
Stéroïdes et Terpénoïdes de Différentes Espèces D'Irésine
Authors: Crabbé Pierre , Azpeitia E. A. , Djerassi Carl 
Published: September 2010

AbstractInvestigation of Iresine pringlei led to the identification of the pentacyclic triterpene friedelin (III) (in the stem), ceryl alcohol (IV), as well as the steroids stigmastanol (VIII), stigmasterol (XI), β‐sitosterol (V) and α‐spinasterol (XII).From Iresine calea were isolated ceryl alcohol and β‐sitosterol.
Considérations Théoriques sur L'Emploi D'Hypobromite de Soude en Milieu Alcalin
Authors: Claeys A. 
Published: September 2010

AbstractLes erreurs mentionnées dans différentes méthodes employant de l'hypobromite, et attribuées à la présence de divers composés dans la solution oxydante, nous a amené à une étude théorique générale concernant l'emploi d'une solution oxydante composée.A l'aide de données graphiques en se basant sur l'inclinaison des droites obtenues, il est possible de calculer le nombre d'électrons échangés dans l'oxydation en milieu alcalin et en milieu acide. En plus, la composition de la solution oxydante peut être déterminée à l'aide du point d'intersection des droites.Les mêmes données indiquent que la détermination à l'aide d'un excès d'hypobromite est indépendante de la composition de la solution oxydante et élimine ainsi les erreurs dues à l'instabilité ou le changement interne de la solution oxydante employée.
Steroïdes CLXXIV Synthèse de Bis — Steroïdes Diacétyléniques
Authors: Crabbé Pierre , Zderic John A. 
Published: September 2010

AbstractThe diacetylenic steroids (VI), (VII) and (X) have been prepared by the cupric acetate — pyridine method. The “bis‐norlutine” (VI) has been partially hydrogenated to the corresponding “diene” (VIII) and the “bis‐acetate” (X a) has been converted to “bis‐ethisterone” (VII).
Higasi's Method for the Determination of Electric Dipole Moments
Authors: Claeys E. G. , van Der Kelen G. P. , Eeckhaut Z. 
Published: September 2010

AbstractDans l'intention de vérifier la généralité de l'équation de Higasi pour la détermination rapide du moment dipolaire de molécules en solution, une série de composés organométalliques et aliphatiques, dissous dans différents solvants apolaires, a été étudiée. De la bonne concordance entre les moments dipolaires obtenus par calcul classique selon Debye (μ.c) et ceux obtenus par l'application de l'équation simplifiée (μH), il résulte que la méthode de Higasi constitue une aide de valeur pour l'étude de substances sensibles à l'air ou à l'humidité.
Contribution A L'étude de L'Anneau Butanique par Spectroscopie Infra‐Rouge
Authors: Chiurdoglu G. , Doehaerd Th. , Duts M. 
Published: September 2010

AbstractThe examination of ∼90 cyclobutanic substances, in the I.R. region of 900‐950 cm−1, indicates that all the components possessing at least one cyclic CH2‐group, free of substitution, presents 1 to 3 absorption bands; one of them at least belonging likely to the vibration γr (CH2). It would thus be easy to recognize the existence of a C4‐ring in such components if there was not the fact, that a great number of non cyclobutanic derivatives also absorb in this region.This work, together with the one of C.H.F. Allen and Coll. permits to close the series of works concerning the direct correlations: I.R., reactions of the alicyclic ring. Except for definite cyclanones, spectroscopy admits only suppositions with regard to the size of the ring.
A New Method for the Preparation of 4,5‐Substituted Δ4‐Oxazoline‐2‐Thiones
Authors: Willems J. F. , Vandenberghe A. 
Published: September 2010

AbstractEen nieuwe methode voor de bereiding van 4,5‐gesubstitueerde Δ4‐oxazoline‐2‐thionen wordt beschreven. Uitgaande van benzoïnen of acyloïnen en thiocyaanzuur (of de zouten hiervan en een zuur) worden met goede opbrengsten Δ4‐oxazoline‐2‐thionen bekomen. In sommige gevallen vormen zich de isomere Δ4‐thiazolin‐2‐onen als nevenprodukten. Enkele gegevens over I.R. spectra en vormingsmechanisme worden eveneens vermeld.
Etudes Spectroscopiques des Molecules Hydroxylees III. Localisation des bandes d'absorbtion v(C–O)H du cyclopentanol, du cycloheptanol et du cyclooctanol
Authors: Chiurdoglu G. , Masschelein W. 
Published: September 2010

AbstractThe ν(C–O) absorption bands of cyclopentanol, cycloheptanol and cyclooctanol are determined by the effects of solvent on the infrared spectrum of these compounds.The possibilities of conformational analysis by this method are discussed.
Étude Infrarouge de Phosphates de Calcium de la Famille de L'Hydroxylapatite
Authors: Winand L. , Duyckaerts G. 
Published: September 2010

AbstractThis article deals with infrared spectroscopic studies, in the range 400‐4000 cm−1, of some calcium phosphates having an apatitic structure. The bands are assigned and small differences between some spectra are explained.Occurrence of free OH− groups in the apatitic cell is confirmed; acidic phosphate groups, linked together by hydrogen bonds, have been detected in the spectra of compounds having a Ca/P value lower than the hydroxylapatite one.Heat effect upon the constitution of these compounds has also been studied; these infrared data get information which could not be obtained by X rays spectrography; i.e. the occurrence of pyrophosphate groups in solid solution in the apatitic cell.The experimental data are satisfactorily explained by the assumption that H+ ions are able to «substitute» progressively Ca++ ions in the apatitic structure.An original formula is proposed for the α tricalcium phosphate.
Structure du Chlorure de Benzoylsalicyloyle et Préparation de Benzodioxanne‐1,3 Ones‐4 Par Action des Dérivés Organocadmiques
Authors: Renson M. , D'Harcour J‐C. 
Published: September 2010

AbstractBien que le chlorure de benzoylsalicyloyle posséde une structure normale déterminée avec certitude par spectrographie infra‐rouge, il donne par action des organocadmiques un dérivé cyclique de la classe des benzodioxanne‐1,3 ones‐4. Par contre, les dérivés obtenus par action des alcools ou des amines possèdent comme lui la structure normale.Sur la base de ces données, ainsi que sur celles fournies par l'identification et la détermination de l'origine des produits secondaires obtenus, nous discutons en détail le mécanisme de la réaction.
Mean Amplitudes of Vibration of some Tetrahedral XY4 Type Molecules‐Part II
Authors: Nagarajan G. 
Published: September 2010

AbstractAs a second paper of this study, the computed values of (1) mean‐square amplitude quantities, (2) generalised mean‐square amplitudes (mean‐square parallel amplitudes, mean‐square perpendicular amplitudes and mean cross products) and (3) mean amplitudes of vibration at the temperatures T=0 and T=298°K have been reported for the molecules GeH4, GeD4, SiH4, SiD4, GeF4 and TiCl4 respectively.
The Friedel‐Crafts Acylation Reaction I. Substituent Effect in the Friedel‐Crafts Benzoylation of Toluene
Authors: Slootmaekers P. J. , Roosen R. , Verhulst J. 
Published: September 2010

AbstractOn a mesuré les constantes de vitesse de la réaction de Friedel et Crafts de chlorures de benzoyle, substitués en para, sur le toluène et dans le chloro‐benzène comme solvant. Des valeurs obtenues à différentes températures on a déduit les paramètres cinétiques des réactions: p.X‐; k2.104 1.mole−1 sec−1 à 20°C; ΔH* kcal/mole; Δs* u.e.: t.Bu‐: 0,63; 14,7; −27,3; Me‐; 0,83; 14,1; −29,0; H‐; 3,51; 13,7; −27,0; F‐; 3,39; 13,8; −27,0; Cl‐; 6,17; 13,1; −28,0; Br‐; 6,77; 13,3; −27,2.Les réactivités globales n'obéissent pas à l'équation de Hammett. On prouve que cela ne peut être attribué à un changement dans la distribution des isomères ou dans le mécanisme de la réaction pour les difféents membres de la série. It est possible qu'une relation linéaire relie l'enthalpie à l'entropie d'activation de la réaction, mais les résultats ne sont pas convaincants. La constante de vitesse dépend de la concentration initiale en complexe réactionnel. Les valeurs de la constante de vitesse obtenues par extrapolation vers une dilution infinie n'obéissent non plus à l'équation de Hammett. Ceci est probablement dû à l'emploi de la concentration du réactif comme paramètre d'extrapolation au lieu d'une propriété physique du mélange réactionnel. Les réactions sont suivies par titration de l'acide chlorhydrique formé dans la réaction et entraîné dans un courant de gaz inerte. Cette méthode expérimentale est discutée et décrite en détail.
The Humulinic Acids Part 1. Isolation and preparation of humulinic acid isomers
Authors: Anteunis M. , Bracke M. , Verzele M. , Alderweireldt F. 
Published: September 2010

AbstractThe isolation and preparation of several humulinic acid isomers named humulinic acid A, B, C and D is reported. They can be obtained by isomerization of the known degradation product of humulone which is the humulinic acid A of the above series.
Essais de Chloration Dirigée VI. Corrélation Structure‐Réactivité Dans la Photochloration des Composés Aliphatiques. Données Expérimentales et Théoriques
Authors: Wautier J. , Bruylants A. 
Published: September 2010

AbstractThe photochemical chlorination of isobutyric acid and its functional derivatives has been undertaken with the aim of completing the data previously collected in this Laboratory on the relative distribution of monochloro‐isomers obtained. The studies bear on the acid, its methyl ester, on acyl chloride and the nitrile. The analysis of the products of chlorination has been effected by gas‐phase chromatography.Samplings taken during the course of the reaction have shown that the concentration of mono‐chlorinated products remain in a constant proportion as long as a certain moleper cent is not exceeded.This conclusion has permitted the integration of the observed orientation effects in free‐radical chlorination into the general problem of structure and reactivity, in establishing a relation between relative ratio of substitution on the one hand and polar and hyperconjugative effects of substituents on the other, of the form:

The application of this equation to the experimental results leads to a negative value for the reaction constant (p = –0,212) and a positive value for the parameter of hyperconjugation (h = +0,114).This relation permits the calculation of the distribution of monochloroisomers for an aliphatic compound at a temperature of about 100°C.
Potential Field and Force Constants of Some Octahedral XY6 Type Molecules
Authors: Nagarajan G. 
Published: September 2010

AbstractA short account of the vibrational analyses for the octahedral XY6 type molecules possessing the symmetry point group On has been reported. The construction and orientation of symmetry coordinates, F and G matrices following the methods outlined by Wilson have been clearly deduced. By making use of the redundant symmetry coordinates a unique set of force constants have been obtained for the molecules SF6, SeF6, TeF6, MoF6, WF6, UF6, NpF6, PuF6, ReF6, OsF6, IrF6 and PtF6 respectively.
A Potentiometric Study of The Silver Complexes of N,N'‐Bis (2‐Hydroxyethyl) Dithio‐Oxamide
Authors: Herman M. , van Poucke L. , Eeckhaut Z. 
Published: September 2010

AbstractIt has been proved that N,N'‐Bis (2‐hydroxyethyl) dithio‐oxamide forms with silver different complexes, dependent from the pH of the solutions and the excess of the metal ion.With an excess of ligand an insoluble yellow complex Ag3H5X4 is formed in the pH range 2,5 to 3,5. The solubility product in strong buffered solution was found to be Ks=10–61,31In the pH range 4 to 6 a more stable yellow complex AgHX is formed with a solubility product Ks=10–19,27.With an excess of silver ion a very unstable white complex Ag2X is formed.
Synthèse de Dérivés Fonctionnels Des Acides Aminés
Authors: Hannart J. , Bruylants A. 
Published: September 2010

AbstractThe authors describe a new synthetic procedure for the preparation of aminocyanoesters, by which they have obtained ethyl‐α‐amino‐γ‐cyanobutyrate (m. 105 °C) and ethyl‐α‐amino‐δ‐cyanovalerate (m. 132 °C). The value of the aminocyanoesters as intermediates in the synthesis of natural or synthetic aminoacids has been demonstrated. Indeed the first one gives on hydrolysis glutamic acid and on reduction dl‐ornithine whereas the second one gives respectively α‐aminoadipic acid and dl‐lysine in moderate yield (ca. 50%).The authors have also studied the nitrosation of aliphatic dinitriles as a means of preparing α‐aminodinitriles. The glutaro‐and adiponitriles can be transformed into their isonitrosoderivatives which are then converted by hydrogenation into the corresponding α‐aminodinitriles. They have thus obtained dl‐glutamonitrile for the first time as its hydrochloride (m. 93 °C).
Détermination du Magnésium Dans Les Fontes Nodulaires Par Analyse Par Activation au Moyen de Deutons Énergétiques
Authors: De Bruyne P. , Hoste J. 
Published: September 2010

AbstractSmall amounts of magnesium confer valuable properties on nodular cast iron. Ordinary chemical and spectrographic methods for determining magnesium in iron are not satisfactory for concentrations below 0,1%, which is the range of interest in the case of cast iron.It is the object of the present work to study the possible application of activation analysis techniques to this problem.It appears that a short bombardment with deuterons of 12 MeV will produce an easily detectable amount of Na22 which will be a measure of the magnesium content of the sample. The iron of the sample itself may be used as an internal monitor through the Fe(d, α)Mn reaction.After correction for the decay of the 6‐day Manganese‐52, the ratio of the Na22 activity to the Mn54 activity is directly proportional to the magnesium content of the iron.In order to measure the sodium and manganese activities, a method for separating them from iron, cobalt and other elements was developed. The procedure studied was based on the use of an anion‐exchange resin.
Studies on the Grignard Reaction‐V polar substituent effects in the grignard addition reaction on substituted acetophenones
Authors: Anteunis M. , van Schoote J. 
Published: September 2010

AbstractRelative reaction rates of fifteen meta and para substituted acetophenones were measured using gas chromatography. With the normal Hammett σ‐values, a linear free energy relationship is found (ρ=+ 0.415), from which strongly conjugative substituents (p. EtO‐, p. MeO‐, p. NMe2‐) deviate. No deviation is found for weak and moderately strong+M substituents. These results are interpreted in the light of a previously proposed (8) reaction mechanism. Resonance contribution can displace the rate‐determining step of the multistep process of the Grignard addition reaction.
Potential Energy Constants, Rotation Distortion Constants and Thermodynamical Properties of GeH3CN and GeD3CN
Authors: Pillai M. G. Krishna , Perumal A. 
Published: September 2010

AbstractThe force constants, obtained from a normal coordinate analysis of the molecules GeH3CN and GeD3CN using Wilson's F.G. matrix method, have been made use in the evaluation of rotational distortion constants for these molecules. Molar thermodynamic properties of these molecules for the ideal gaseous state at one atmospheric pressure, with rigid rotor harmonic oscillator approximation have also been obtained.
Étude des Propriétés du Chlorure D'O‐Chlorosélénobenzoyle Application À la Synthèse D'O‐Alcoylsélénoacylophénones
Authors: Renson M. , Piette J‐L. 
Published: September 2010

AbstractContrairement à son isologue sulfuré, l'acide o‐méthylsélénobenzoïque ne se transforme pas en son chlorure sous l'action du chlorure de thionyle mais bien en chlorure d'o‐chlorosélénobenzoyle. La rupture de la liaison Se‐C aliphatique d'un sélénoéther arylaliphatique sous l'effet de ce réactif semble générale à la lumière des différents cas étudiés.Le chlorure d'o‐chlorosélénobenzoyle a cependant pu être utilisé avec succès pour la préparation des o‐alcoylsélénoacylophénones à partir des dérivés organocadmiques.En vue d'une étude infra‐rouge à publier très prochainement un certain nombre de dérivés nouveaux de ce chlorure, ainsi que plusieurs dérivés sulfurés semblables également inconnus ont été préparés dans ce travail.
Isomérie de Position et Spectres de Masse II‐Triméthylcycloalcanes et méthyléthylcycloalcanes à cycle en C3, C5 et C6
Authors: Natalis P. 
Published: September 2010

AbstractMass spectra of position isomers have been examined in three series of cyclic hydrocarbons, (a) trimethylcycloalkanes with C3, C5 or C6 ring, (b) methylethylcyclopentanes and (c) gem derivatives of methylethylcycloalkanes with C3, C5 or C6 ring. Correlation rules of some features of mass spectra with molecular structure are attempted i.e. abundances of molecular ions P+ and fragment ions corresponding to the loss of C1 or C2 groups, (P‐CH3)+, (P‐C2H5)+ and (P‐C2H4)+.As a result it is shown that correlation rules of branched hydrocarbons can generally be applied to the bi‐and trialkylcycloalkanes investigated. In addition new correlation rules for cyclic hydrocarbons can be deduced from the present work and specific correlations for C5 and C6 rings are suggested.
Potential Energy Constants, Rotational Distortion Constants and Mean Square Amplitudes of Vibration of Some XY3Z Type Monohalogermanes
Authors: Pillai M. G. Krishna , Perumal A. 
Published: September 2010

AbstractPotential energy constants for the molecules GeH3F and GeH3Br have been calculated using the observed fundamental frequencies and potential function consisting of all significant valence potential constants. Also included in this paper are the calculated values of rotational distortion constants and mean square amplitudes of fundamental vibrations for these molecules as well as for the molecules GeH3Cl and GeD3Cl.
Modification de la Fonction Carboxy de la Pénicilline
Authors: Claesen M. , Vanderhaeghe H. 
Published: September 2010

AbstractLa fonction carboxy de la pénicilline V (I, R=C6H5OCH2−, X=OH) a été transformée en fonction alcool, par réduction de l'azide avec du LiBH4. L'azide a permis aussi la synthése du benzylcarbamate. Lors de la réduction de l'ester de la pénicilline V, la fonction ester et le carbonyle du β‐lactam sont réduits par le LiBH4.
Grignard Reaction VIII. On the Bimolecular Nature of the Grignard Reagents
Authors: Anteunis M. 
Published: September 2010

AbstractIt is the purpose of this paper to show that in contrast with the now widely accepted view (see f.i. ref. 1) the bimolecular form of the Grignard reagent (I) is not necessarily the unique active species. In most cases the activity can just as well be attributed to the monomolecular form. Undoubtedly several forms including the monomeric are actually present in the solutions, but the question is which species is responsible for the Grignard reactions?
Préparation de Styrènes α, β Disubstitués
Authors: Barbieux M. , Martin R. H. 
Published: September 2010

AbstractSeveral mixtures of unsaturated esters were obtained by dehydration of hydroxyesters (Ia→Ih) (from a Reformatsky reaction) and each constituent, after separation by gas liquid chromatography, was assigned either the α, β‐ or the β, γ‐unsaturated ester structure following the observed νc‐0 frequency and the cis or trans configuration. The less rigid non‐conjugated ester is formed predominantly or exclusively when steric strain prevents conjugation in the “conjugated” isomer. α, β dialkylstyrenes were obtained after hydrolysis and decarboxylation and this last reaction proceeds with concomitant shift of the double bond, α β dialkylstyrenes were obtained also through dehydration of appropriate tertiary alcohols (from a Grignard reaction). Attribution of geometric configuration for the α, β dialkylstyrenes and the β, γ unsaturated esters was realised on the basis of volatility and U.V. spectrum according to Cram's method.
Structure Moléculaire de Trois Complexes du Fer‐Carbonyle Avec L'Acétylène et Ses Dérivés
Authors: van Meerssche M. , Piret P. , Meunier‐Piret J. , Degrève Y. 
Published: September 2010

AbstractDétermination par diffraction des R.X. de l'architecture moléculaire de trois complexes du fer‐carbonyle: 2 isomères de Fe2(CO)6 (C2H2)3 et Fe2(CO)6 (C6H5.C6H5). Dans les trois molécules les ligands organiques subissent un remaniement important de manière á permettre la formation d'édifices diamagnétiques obéissant à la règle du gaz rare pour les atomes de fer.
A Thermodynamic Study of the Dissociation of Aniline Hydrochloride
Authors: Aboul‐Seoud A. 
Published: September 2010

AbstractThe distribution of aniline between benzene and aqueous sodium chloride solutions was studied at 10, 25 and 35°C. The data obtained was used to calculate the activity of the amine under the different conditions.The dissociation of aniline hydrochloride was studied at different temperatures, different concentrations and in presence of different concentrations of sodium chloride, by the distribution method.5 The ratio of the activity coefficients of hydrogen and anilinium ions was calculated for the different conditions. The relationship between the activity of the free amine in water, and salt concentration, was studied.
Mean Amplitudes of Vibration, Bastiansen‐Morino Shrinkage Effect and Thermodynamic Functions in some Intergroup IVA Molecules
Authors: Nagarajan G. 
Published: September 2010

AbstractMean amplitudes of vibration for the GeC2, Ge2, Ge2Si and GeSiC molecules possessing a linear asymmetrical structure with the point group C∞ ν have been calculated on the basis of the principle postulated by Cyvin. A brief description of the Bastiansen‐Morino shrinkage effect has been narrated with an analytical expression for this molecular system. The calculated values of the shrinkages at the temperatures T=0, T=298°K and T=500°K are reported. The molar thermodynamic functions have also been computed for the temperature range 100‐2000°K with an assumption of a rigid rotator, harmonic oscillator model.