bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biochemical production of dihydroxyacetone from glycerol
Authors: Rutten A. M. G. 
Published: September 2010

AbstractDihydroxyacetone (propanediolone) has been prepared from glycerol by the action of Acetobacter suboxydans var. biourgianum, nov. var. Kluyver and de Leeuw.It was found that the high values in the production of the ketose, obtained by several investigators, are not due to a hypothetical reducing impurity, present in the medium, but to erroneous data appearing in the literature concerning the reducing power of the dihydroxyacetone. Moreover, it was shown that during the conversion of the glycerol, some pyruvic acid and a fluorescing substance were formed. The latter displayed absorption bands at 273 mμ and 450 mμ.
Inhibition of photogalvanic phenomena
Authors: Weber K. , Matijević E. 
Published: September 2010

AbstractSolutions of thionine give in presence either of thiosine‐amine or diethyl‐thiosine‐amine pronounced photogalvanic effects, the numerical values of which amount to over 400 mV. Under the influence of light, the redox‐potential of the system becomes more negative. These effects are closely related to the photochemical bleaching of thionine. In regard to the rate of increase, as well as to the influence of light, the photogalvanic effect may be interpreted by means of the general kinetic equation of photochemical kinetics.The photogalvanic effects of thionine are strongly inhibited by various inorganic salts and polyphenols. Reducing agents stabilise these systems in such a way that the initial redox‐potential of the electrode becomes negative, while for oxidizing agents the stabilization potential takes much more positive values. Apart from inhibition, the addition of foreign substances brings about electrolytic as well as other effects which increase numerical values of photogalvanic effects.Other thiazinic and azinic dyes show also photogalvanic effects. It is probable that there is a close connection between their normal redox‐potentials and the magnitude of photogalvanic effect.
Spectrophotometric study of the solvation of iodine in dioxan solution
Authors: Ketelaar J. A. A. , van de Stolpe C. , Gersmann H. R. 
Published: September 2010

AbstractThe solvation of iodine in dioxan‐carbon tetrachloride solutions was studied by determining a large number of absorption spectra at different compositions and different temperatures. The concentration of the iodine‐dioxan complex was derived from the extinction at 4515 Å (at 17° C), the wavelength of maximal absorption of iodine in pure dioxan, as compared with the extinction of iodine in pure dioxan and in pure carbon tetrachloride, respectively. Application of the mass law resulted in equilibrium constants essentially independent of concentration. However, this was only the case when based on the assumption of a ratio of 1:1 for the composition of the complex. From the dependance on temperature the heat of formation of the complex was found to be 2700 cal/mol.
The behaviour of membranes between electrolyte solutions: I. The relation between pH and the membrane potential across cellophane
Authors: Hirsch P. 
Published: September 2010

AbstractThe behaviour of membranes in contact with electrolyte solutions has been studied as regards both electrical potential differences between the two sides of the membranes and the movement of dissolved substances as well as solvent (water) through the membrane. This first communication deals with potential measurements on “cellophane” membranes through which KCl and NaCl solutions diffused towards solutions of ten times smaller concentrations of the same salt. The pH was maintained the same on both sides of the membrane. It was found that pH had a great influence on the measured membrane diffusion potential (MP) (table III).The difference Δ between MP and the liquid junction potential (LJP) was the same in KCl and in NaCl experiments. Δ increases with the pH according to a curve (fig. 1) which is very similar to the dissociation curve of a monobasic acid. There is apparently a close correlation between MP (or Δ) and the dissociation of acid groups in the membrane substance.
The nitrosation of methallylchloride
Authors: Kooyman E. C. , Farenhorst E. , Werner E. G. G. 
Published: September 2010

AbstractThe action of aqueous nitrous acid on 2‐chloromethylpropene‐1 (methallylchloride) results in the formation of an unstable addition product which is converted into 1‐chloro‐2‐methyl‐3‐nitropropene‐1 upon treatment with alkali. For this new compound, the name nitro isocrotyl chloride is proposed. Its structure was established by ozonolysis, which yielded nitroacetone and hydrogen chloride.Dinitrogen tetroxide acts upon methallyl chloride to give a nitronitrite, which may be converted into a nitroalcohol upon treatment with methanol. This nitroalcohol has the probable structure formula 2‐chloromethyl‐1‐nitro‐propanol‐2.
Vapour pressures of saturated ammonium bicarbonate solutions
Authors: Zernike J. , Haider S. Z. , Jaheruddin Md. , Rahman F. 
Published: September 2010

AbstractCritical survey of literature. The system ammonium bicarbonate‐water is ternary. Measurements of the vapour pressures of the solutions as function of the volume of the gaseous phase, down to zero volume, at different temperatures. The vapour phase is found to contain no weighable amounts of ammonia.
The benzoyl peroxide initiated addition of carbon tetrachloride to olefins
Authors: Kooyman E. C. , Farenhorst E. 
Published: September 2010

AbstractThe initiation, propagation and termination steps of the benzoyl perioxide initiated additon of carbon tetrachloride to olefins are described.Initiation follows two main routes, viz. a) addition of benzoate and of phenyl radicals to the olefinic double bond, followed by chlorine abstraction from carbon tetrachloride by the new radicals and b) formation of trichloromethyl radicals from carbon tetrachloride and phenyl radicals.The propagation mechanism proposed by Kharasch et al.2) is confirmed and the extent of telomer *) formation estimated for the case of cetene.Chain termination consists in the formation of stable allyl‐type radicals, which are incapable of starting a new chain; in the case of cyclohexene, these radicals were found in the form of their dimer 3,3′‐dicyclohexenyl.Supporting evidence is based on detailed analyses of the reaction mixtures, peroxide decomposition products and other by‐products being isolated and identified. Further arguments follow from the influence of retarders and the results obtained with olefins of a special structure.
The constitution of dihydro‐nicotyrine (“N‐methyl‐myosmine”)
Authors: Wibaut J. P. , Beyerman H. C. 
Published: September 2010

AbstractThe structure of the dihydronicotyrine obtained by zinc‐hydrochloric acid reduction of 3,2′‐nicotyrine (I) has for some time been established by chemical means as N‐methyl‐myosmine (II). Recently spectroscopic and chemical evidence has been published which is contrary to this opinion.These spectroscopic findings have been confirmed and extended by the inclusion of 3‐allyl‐pyridine in this investigation.Oxidative degradation of dihydronicotyrine hydrochloride with ozone gave nicotinic acid hydrochloride in approximately 85% yield. This is in accordance with the structure of N‐methyl‐myosmine (II), if a “normal” degradation is assumed. In view of other investigations on “abnormal fission” of double bonds with ozone, we are inclined to regard this evidence as inconclusive.Therefore structures III and IV have to be considered as representing dihydronicotyrine, and from these III seems most probable.A new and convenient synthesis of (pyridyl‐3)‐acetic acid is reported.
Kinetical experiments on ozonisation reactions: II. The ozonisation of benzene
Authors: Sixma F. L. J. , Boer H. , Wibaut J. P. , Pel H. J. , de Bruyn J. 
Published: September 2010

AbstractThe velocity of the ozonisation of benzene in chloroform is proportional to the concentration of benzene and that of ozone. The reaction constant was determined at eight temperatures between −25 and −40° C.The reaction takes place about three times more rapidly in nitromethane than in chloroform.Aluminium chloride and ferric chloride catalyse the reaction; the velocity increases directly with the concentration of aluminium chloride.The results of our measurements are in agreement with the reaction mechanism suggested in a previous publication.
Syntheses with the aid of lithiopyridines: Preparation of di‐pyridyl ketones, pyridyl‐phenyl‐carbinols and tri‐pyridyl‐carbinols
Authors: Wibaut J. P. , de Jonge A. P. , van der Voort H. G. P. , Otto P. Ph. H. L. 
Published: September 2010

AbstractThe preparation of phenyl pyridyl ketones by the action of 2‐lithiopyridine or 3‐lithiopyridine on benzoic anhydride, ethyl benzoate or benzonitrile is described: di‐pyridyl‐phenyl‐carbinols are produced by the further action of lithiopyridine on the ketones so obtained.The action of 2‐lithiopyridine on 2‐cyanopyridine or ethyl picolinate gives bis‐(pyridyl‐2) ketone; in a similar way bis‐(pyridyl‐3) ketone is prepared and some other di‐pyridyl ketones.By the action of 2‐lithiopyridine on bis‐(pyridyl‐2) ketone there is obtained tris‐(pyridyl‐2)‐carbinol; tris‐(pyridyl‐3)‐carbinol has been synthesised in a similar way.
Reaction products of primary β‐hydroxy‐amines with carbonyl compounds. IX. Etude magnétochimique
Authors: Metzger J. , Pacault A. 
Published: September 2010

AbstractMalgré quelques difficultés rencontrées dans le calcul des susceptibilités magnétiques, les résultats obtenus dans l'étude magnétochimique de plusieurs des substances examinées dans le précédent mémoire (VIII) corroborent pleinement les conclusions de ce dernier.
The synthesis of N‐(ϵ‐aminocaproy L‐) ϵ‐aminocaproic acid. „Di‐ϵ‐aminocaproic acid”︁.
Authors: van der Want G. M. , Staverman A. J. 
Published: September 2010

AbstractThe possibility of synthesizing ω‐peptides by condensation of a ω‐phthalimido acid chloride with a ω‐amino acid and subsequent treatment with hydrazine has been investigated.The synthesis of N‐(ϵ‐aminocaproyl‐) ϵ‐aminocaproic acid is described.
Polypeptides. I. N.‐Carbonic anhydrides, (NCA) of some amino acids. (4 substituted oxazolid‐2,5 diones)
Authors: Petri E. M. , Staverman A. J. 
Published: September 2010

AbstractThe preparation of the N‐carbonic anhydrides and the carbomethoxy compounds of the following amino acids is described: glycine, valine, leucine, norleucine, phenylalanine, proline and cystine.
The addition of ozone to aromatic bonds
Authors: Badger G. M. 
Published: September 2010

AbstractSome properties of “double bond reagents” are discussed, and the mechanism of the reaction between ozone and aromatic compounds as proposed by Wibaut and his co‐workers, is criticised. It is suggested that the initial stage in the reaction is the formation of a π‐bond between the carbon‐carbon bond having the highest double bond character and the ozone molecule.
Time‐dependence of boundary tensions of solutions: IV. Kinetics of adsorption at liquid‐liquid interfaces
Authors: Ward A. F. H. , Tordai L. 
Published: September 2010

AbstractVarious mechanisms are considered which might explain the variation of interfacial tensions with time, when fatty acids are adsorbed from hexane on to a hexane water interface. In these solutions there are both single and associated molecules of the fatty acids. Although the single molecules are the adsorbable species, it is shown that the slow adsorption cannot be attributed to their relative scarcity. The Langmuir adsorption isotherm is found not to apply accurately at equilibrium, and a new isotherm is proposed. A mechanism is suggested to explain the kinetics of adsorption and desorption and is found to be in accordance with the experimental variation of interfacial tension with time. Velocity constants for adsorption (kt) and desorption (k2) are evaluated. The resulting equilibrium constants (k1/k2) are found to agree well with equilibrium constants deduced thermodynamically by an entirely independent process. The effect of temperature on the processes of adsorption and desorption is also discussed.
Arenicochrome: Degradation to arenicochromine, a sulphur‐free pigment
Authors: van Duijn P. 
Published: September 2010

AbstractThis paper contains a description of the hydrolysis of arenicochrome in acid milieu. This leads to the splitting off of all the sulphur in the arenicochrome molecule in the form of sulphuric acid and results in the preparation of a sulphur‐free crystalline derivative of arenicochrome. The name arenicochromine is proposed for this violet pigment. The composition of arenicochromine accords with the formulae C42H34O16 or C42H34O16.The absorption spectra as well as some other properties of arenicochromine are reported.
Titration curves of dialysed clay minerals
Authors: van Schuylenborgh J. , Vervelde G. J. 
Published: September 2010

AbstractTitration experiments were carried out on dilute suspensions of dialysed samples of three clay minerals, viz. kaolinite, illite and bentonite. Sodium and potassium hydroxide solutions were used as titration liquid. Both the hydrogen and the sodium or potassium ion activities were measured by means of glass electrodes. The titration curves were analysed on the basis of a theory, describing the clay suspensions as a system of two solutions, one containing the clay acid and the other being responsible for the activities measured. The interrelation of the composition of these solutions can be expressed by the laws of the Donnan equilibrium. There is reason to reconsider the traditional view, that the properties of clay acids cannot be described by one or a few dissociation constants.
Apparent osmotic pressure of solutions of heterodisperse polymers
Authors: Staverman A. J. 
Published: September 2010

AbstractThe theory of apparent osmotic pressure obtained with membranes which are partially permeable to the solute is applied to solutions of heterodisperse polymers. An expression for the relation between the measured osmotic pressure and the permeability of the membrane is derived and it is shown how molecular distributions of polymers can be obtained from simultaneous measurements of permeability and osmotic pressure with a given polymer‐solvent‐system and different membranes.
Amides X: The use of tertiary amides in the perkin reaction
Authors: Parkes E. A. , Polya J. B. , Spotswood T. M. 
Published: September 2010

AbstractThe effects of basic catalysts and temperature on the condensations of benzaldehyde with N‐methyldiacetimide, N‐phenyldiacetimide, N,N‐dimethylacetamide and N,N‐diphenylacetamide respectively have been studied. These condensations have little practical value but the isolation of N‐cinnamoyl acetanilide from the reaction between benzaldehyde and N‐phenyldiacetimide proves that dehydration precedes deacylation during the Perkin reaction involving tertiary amides.
Synthèse de Provitamines D À Chaînes Latérales Variées
Authors: de Vries Harmen , Backer H. J. 
Published: September 2010

AbstractAprès avoir synthétisé quelques Δ5‐stérols ayant des chaïnes latérales différentesMémoires antérieurs: Rec. trav. chim. 69, 759. 1252 (1950).
), les auteurs y ont introduit une seconde liaison double en position 7. Ainsi ils ont obtenu cinq Δ5,7‐stérols nouveaux (provitamines D). dont, après irradiation, l'activité a été examinée.Plusieurs tentatives pour préparer de tels composés aux dépens d'ergostérol n'ont pas conduit au résultat désiré, par suite de la difficulté de protéger réversiblement la double liaison conjuguée.
Méthylation du Bis‐Méthylsulfonyl‐Nitrométhane au Moyen de Iodure de Méthyle: (Propriétés du groupe sulfonyle XXVII))
Authors: Backer H. J. 
Published: September 2010

AbstractL'iodure de méthyle réagissant sur le dérivé argentique du bis‐méthylsulfonyl‐nitrométhane fixe un groupe méthyle sur l'atome de carbone central. La structure du produit résulte de l'hydrolyse et de la pipéridinolyse, qui s'accomplissent sans retard à la température ambiante et qui, en expulsant un groupe méthylsulfonyle, conduisent au 1‐méthylsulfonyl‐1‐nitro‐éthane; la synthèse de ce dernier composé à partir du 1‐bromo‐1‐nitro‐éthane confirme la structure donnée:
Une nouvelle preparation des pyridylaldehydes
Authors: Wibaut J. P. , Huls R. 
Published: September 2010

AbstractLe diéthylacétal du pyridyl‐3‐méthanal, obtenu à partir de 3‐bromopyridine, selon la méthode de Wibaut et van der Voort, a été transformé, avec un rendement de 84%, en pyridyl‐3‐méthanal.Le pyridyl‐2‐méthanal a été de même préparé, avec un rendement de 78%, à partir de l'acétal correspondant, obtenu par condensation de l'orthoformiate d'éthyle avec le bromure de pyridyl‐2‐magnésium.
The thermal decomposition of (—)∼menthyl esters
Authors: Wibaut J. P. , Beyerman H. C. , van Leeuwen H. B. 
Published: September 2010

AbstractIt has been reported in the literature by various investigators that the pyrolysis of (—)‐menthyl acetate (in the gas phase) results in the formation of (+)‐p‐menthene‐3 only.We investigated the thermal decomposition of (—)‐menthyl acetate in the gas phase and of (—)‐menthyl stearate in the liquid state. It was found that the two methods give about the same yield of terpene. This terpene is a mixture essentially consisting of (+)‐trans‐p‐menthene‐2 (33—36%) and of (+)‐p‐menthene‐3 (67—64%)The infrared spectra of these mixtures agree with the spectrum given in the literature for “(+)‐p‐menthene‐3”. A statement in the literature with regard to characteristic infrared absorption of unsaturated hydrocarbons seems to have no application to this case
Electrophoretic determination of the equivalent weight of β‐lactoglobulin from the changes in concentration at the δ or ϵ boundary
Authors: Wegelin E. , de Wael J. 
Published: September 2010

AbstractThe equivalent weight of β‐lactoglobulin at pH = 6.8 and μ = 0.15 has been calculated from a Tiselius experiment by the method given in a previous paper and elaborated in this paper. The result: E = 2.710, agrees reasonably well with the value E = 3.130 calculated from the dissociation curve. The agreement between the two results would be better, if an accurate calculation of the Donnan equilibrium were possible
Preparation of 2‐ethoxy‐4‐diethylaminobenzene‐1‐diazoniumborofluoride
Authors: Klaassens K. H. , Schoot C. J. 
Published: September 2010

AbstractThe preparation of 2‐ethoxy‐4‐diethylaminobenzene‐1‐diazoniumborofluoride is described. A stable diacetyl derivative is formed by treating 2‐ethoxy‐4‐diethylamino‐1‐aminobenzene with acetic anhydride.
The acid catalyzed cannizarro reaction of formaldehyde
Authors: Prins H. J. 
Published: September 2010

AbstractIt is shown that formaldehyde undergoes an acid catalyzed Cannizarro reaction in an acetic‐sulphuric acid medium as well as in an aqueous solution of sulphuric acid.In an acetic‐sulphuric acid medium the reaction slows down when the sulphuric acid content is increased above a certain maximum.In the same medium acetaldehyde is hydroxymethylated by formaldehyde a reaction which is followed by a crossed Cannirarro leading to esters of pentaerythritol and to its diformal compound (2,4,8,10‐tetraoxa‐6‐spiro‐undecane) which is easily prepared from the components in acid solution.These reactions explain the formation of 2‐methyl‐2‐hydroxymethyl triacetate S. Olsen, Z. Naturforschung 1, 676 (1946); Chem. Abstr. 44, 1130 (1950); J. W. Baker, J. Chem. Soc. 1948, 89.
in the condensation between ethene and formaldehyde.
Complex‐chlorides I. PCl5‐compounds. Preliminary communication
Authors: Groeneveld W. L. 
Published: September 2010

AbstractDuring an investigation on the structure and the behaviour of addition‐compounds of PCl5 with the chlorides of elements, which do not belong to the alkali and alkaline earth metals, it turned out that a few compositions reported in the literature were wrong. Several new compounds have been prepared.
Steric effects on mesomerism. X . Deacylation of some tert.butyl‐acetylamino‐nitrobenzenes in an alkaline medium
Authors: Biekart H. J. B. , Dessens H. B. , Verkade P. E. , Wepster B. M. 
Published: September 2010

AbstractThis paper contains data on the influence of a tert.butyl group on the rate of catalytic alkaline deacylation of nitro‐acetanilides. Various cases of a steric effect on the mesomerism are discussed.
The preparation of higher fatty acids with an odd number of carbon atoms by the Arndt‐Eistert synthesis
Authors: Links J. , De Groot M. S. 
Published: September 2010

Abstract
Pentadecanoic, heptadecanoic and nonadecanoic acid were prepared from respectively myristic, palmitic, and stearic acid by the Arndt‐Eistert synthesis. The use of the Wilds and Meader variation for the rearrangement of the alkyldiazoketones, involving heating at 180° C with octanol‐2 or benzyl alcohol and γ‐collidine, gave fairly pure fatty acids. The reaction proceeded fast, and good yields were obtained. The advantage over the conventional Ag2O‐methanol method was especially marked in the case of nonadecanoic acid.
A chromatographic procedure, using silicagel as an adsorbent, petroleum ether as a solvent, and petroleum ether plus 25% ether as an eluent, was developed. This allowed a further purification of the products to pure fatty acids.
Une méthode générale de synthèse des acides gras supérieurs linéaires ou ramifiés
Authors: Buu‐Hoï N. G. Ph. 
Published: September 2010

AbstractOn décrit dans ce travail une méthode générale de synthèse des acides gras supérieurs dont la chaîne hydrocarbonée peut être linéaire ou ramifiée en des positions déterminées. Trois synthèses sont données en exemple: celles des acides palmitique, stéarique, et 15‐méthylpentadécanoïque.
On the separation of α‐keto acid dinitrophenyl‐hydrazones by ionophoresis and their polarographic estimation
Authors: Neish William J. P. 
Published: September 2010

AbstractRapid separation of synthetic mixtures of the 2,4‐dinitrophenylhydrazone derivatives of α‐keto acids has been effected by paper electrophoresis. The method has been applied to the separation of these derivatives from animal tissues and a polarographic procedure has been devised for the estimation of the hydrazones. Keto acid analyses are presented for organs from normal and tumour‐bearing rats.
The preparation of two new tetra‐alkoxysilanes
Authors: Breederveld H. , Waterman H. I. 
Published: September 2010

AbstractCyclohexoxy‐ and pentoxy‐3 tri‐tert.butoxysilane have been prepared from tri‐tert.butoxychlorosilane and the respective alcoholates. The specific refractions of these compounds deviate from the value calculated according to Smith1).
The effect of ortho methyl groups on the methylsulphonyl group, compared with their influence on the nitro group: (Properties of the sulphonyl group XXXIII
Authors: Kloosterziel H. , Backer H. J. 
Published: September 2010

Abstract4‐Methylsulphonyl‐3,5‐xylenol has been prepared by a series of reactions involving thiocyanation, reduction with LiAlH4, methylation, and oxidation. The methylsulphonyl group exerts a negative mesomeric effect, which, however, is not hindered by ortho methyl groups. The spectrum as well as the ionization constant prove this. For the latter property, additivity of Hammett's σ‐constants for groups in the 3, 4, and 5 positions was taken as a criterion. For sulphur, as a second‐row element, coplanarity of its SO‐valencies and the benzene nucleus is no condition for maximum resonance. Throughout this paper, the data of the corresponding nitro compounds have been measured for comparison.