Untersuchungen über das Verhalten organischer Mischphasen. 4. Mitteilung. Dampfdrücke,thermodynamische Mischungsfunktionen und Brechungsindizes der binären Systeme Tetrahydrofuran-Diäthyläther und Methanol-Tetrahydrofuran bei 25°

The total vapor pressure and the heats of mixing of the system tetrahydrofurane-diethyl ether, and methanol-tetrahydrofurane were measured at 25°C. The index of refraction was used to determine concentrations for the total pressure measurements. The partial pressures, activity coefficients, excess free energies, and entropy functions were calculated.     

Untersuchungen über das Verhalten organischer Mischphasen 5. Mitteilung Dampfdrücke. therodynamische Mischungsfunktionen und Brechungsindices des binären systems Cyclohexan - diäthyläther bei 25°

The total vapor pressures and the heats of mixing of the system cyclohexane-diethyl ether were measured at 25°C. The index of refraction was used to determine concentrations for the total pressure measurements. The partial pressures, activity coefficients, excess free energies, and entropy functions were calculated.     

Untersuchungen über das Verhalten organischer Mischphasen 8. Mitteilung. Dampfdrücke,Dichten, thermodynamische Mischungsfunktionen und Brechungsindices der binären Systeme Wasser-Tetrahydrofuran und Wasser-Diäthyläther bei 25°

The total vapor pressures and the heats of mixing of the water-tetrahydrofuran and water-diethyl ether systems were measured at 25°. Density, index of refraction, and KARL -FISCHER -titration were used to determine concentrations for the total pressure measurements. The partial pressures, activity coefficients, excess free energies, entropy functions, and excess volumes were calculated.     

Untersuchungen über das Verhalten organischer Mischphasen 7. Mitteilung. Dampfdrücke,Dichten und thermodynamische Mischungsfunktionen des binären Systems Cyclohexan- Tetrahydrofuran bei 25°

The total vapor pressures and the heats of mixing of the system cyclohexane-tetrahydrofuran were measured at 25°C. The density was used to determine concentrations for the total pressure measurements. The partial pressures, activity coefficients, excess free energies, entropy functions, and excess volumes were calculated.     

Untersuchungen über das Verhalten organischer Mischphasen. 6. Mitteilung. Dampfdrücke,Dichten, thermodynamische Mischungsfunktionen und Brechungsindices des binären Systems Methanol-Diäthyl-äther bei 25°

The total vapor pressures, the heats of mixing, and the refractive indices of the system methanol-diethyl ether were measured at 25°C. The density was used to determine concentrations for the total pressure measurements. The partial pressures, activity coefficients, excess free energies, entropy functions, and excess volumes were calculated.     

Massenspektrometrische Identifizierung und Synthese isomerer und homologer Spermidin- und Spermin-Derivate. 25. Mitteilung über das massenspektrometrische Verhalten von Stickstoffverbindungen. 161. Mitteilung über Alkaloide

Synthesis of isomeric and homologous spermidine and spermine derivatives and their identification by mass spectrometry. The structure of homologous and isomeric spermidines and spermines follows from mass-spectroscopical analysis of their peracetyl (see text, footnote 3) (Table 1) or tosyl-acetyl (Table 2) derivatives. In the case of the peracetyl compounds, triads of peaks are recorded which, according to the number of methylene groups between the nitrogen atoms, show mass numbers characteristic for each of the substances (Scheme 1, ions b , d , e and c ). On the basis of cyclic ions of type f (Scheme 2), occurring in the mass spectra of N-acetyl derivatives, tosylated on a secondary amino nitrogen atom, deductions can be drawn as to the number of methylene groups between neighbouring tosylated and acetylated nitrogen atoms in these compounds.     

Kinetische Untersuchungen über Substitutionsreaktionen an Metallkomplexen. 9. Mitteilung [1]. Kinetik und Mechanismus der Reaktion von Hexamethylborazolchrom-tricarbonyl mit tertiären Phosphinen und Phosphiten [2]

Hexamethylborazolechromium tricarbonyl B₃N₃(CH₃)₆ Cr(CO)₃ reacts with tertiary phosphines and phosphites under surprisingly mild conditions by cleavage of the ring-to-metal bond. For L = trialkylphosphines and trialkyl- or triaryl-phosphites, compounds of the general composition cis-Cr(CO)₃L₃ are formed, whereas for L = triphenyl- and tricyclohexyl-phosphine the complexes trans-Cr(CO)₄L₂ are obtained. The kinetics of the reaction of B₃N₃(CH₃)₆ Cr(CO)₃ with phosphites P(OR)₃ (R = CH₃, C₂H₅, C₆H₅) have been studied by means of spectrophotometric methods. The second-order rate law indicates a primary, rate-determining attack of the phosphite to either the metal atom or the ring ligand of the borazole complex. This attack is favoured by an extremely low activation energy. The mechanism of the substitution process is discussed in detail, and the reactivity of the hexamethylborazole compound is compared with that of other half-sandwich type complexes.     

Reaktionen von Glutaminsäuredimethylester im Massenspektrometer. 21. Mitteilung über das massenspektrometrische Verhalten von Stickstoffverbindungen

The mass spectral fragmentation of dimethyl glutamate ( 1 ) and its deuterated derivatives 1a , 1b and 1c has been investigated. By loss of a methoxycarbonyl group from the molecular ion an ion of m/e 116 is generated. The latter splits off methanol (m*), the resulting fragment of m/e 84 giving raise to the base peak of the spectrum. Only part of the hydrogen transferred to the leaving group originates from thc amino group, as was suggested earlier [2] [3]. Basing on experiments with deuterated compounds we propose an additional mechanism for the reaction, i.e. hydrogen transfer from C(3) to methoxyl. The fragment generated by both processes is most likely to be a pyrrolinonium ion. Thermal side reactions in the mass spectrometer (formation of pyroglutamic acid ester) followed by fragmentation may lead to the same ion. – The mechanisms discussed are supported by the mass spectral fragmentation of N-acetyl-glutamic acid diesters 3 , 3a , 3b and 3d and of the N, N-dimethyl derivatives 4 and 4a . – The fragmentation reactions investigated are similar to some of 1,3-trimethylenediamine derivatives [7]. This means that there are parallels in the mass spectral fragmentation of difunctional compounds irrespective of the nature of the functional groups.     

Untersuchungen über die reaktionsfähigkeit von chrom und titan mit pyrrolidindithiocarbaminat

The dependence of the reactivity with pyrrolidinedithio-carbamate of titanium on pH and the presence of other ions, and of chromium^III on the state of binding of the chromium^III ion and on pH have been investigated. The results of this investigation provide an explanation of the hitherto very variable accounts of the reactivity of titanium and chromium with disubstituted dithiocarbamates.

Résumé

Les auteurs étudient l'influence du pH et de la la présence d'autres ions sur le pyrrolidinedithiocarbamate de titane et l'influence du pH et de l'état sous lequel se trouve le chrome (III) en solution sur le pyrrolidinedithiocarbamate de chrome (III). Les résultats obtenus permettent d'expliquer les différences rencontrées quant aux réactions du chrome et du titane avec les dithiocarbamates bisubstitués.     

Methode zur Konstitutionsaufklärung der Reaktionsprodukte der Umsetzung von Cellulose mit Formaldehyd. 18. Mitteilung über textilchemische Untersuchungen [1]

(1) A method is described which allows the elucidation of the structure of cotton cross-linked with formaldehyde. It consists of a permethylation process (5 methylations with dimethyl sulphate and sodium hydroxide in dimethyl sulphoxide, followed by two exchange methylations of the formalised sodium cellulosate with methyl iodide in n-butanol), hydrolysis of the product in 72% sulphuric acid to the respective methylated glucoses, reduction of the mixture of glucoses to the respective sorbitols, blocking of all free hydroxyl groups by acetylation, trifluoroacetylation or formation of trimethylsilyl ethers, and vapour phase chromatographic separation of the derivatives. (2) It is shown that after permethylation practically no free hydroxyl groups can be detected and that scarcely any replacement of methylene or oxymethylene cross-links by methyl groups has taken place. With the exception of losses in filtration of the permethylation product, all stages of the process proceed on an almost quantitative basis.     

Untersuchungen über N-Methoxyguanidin 2. Umsetzungen mit Chlordithioameisensäureethylester und mit Kohlenstoffdisulfid,Acetylierungsreaktionen [1]

Studies on N-Methoxyguanidine. 2. Reactions with the Ethylester of Chlorodithioformic Acid and with Carbon Disulfide, Acetylation Reactions The reaction of N-methoxyguanidine with the ethylester of chlorodithioformic acid yields the known 3-amino-5-ethylthio-1,2,4-thiadiazole. With carbon disulfide no reaction occurs. N-Methoxyguanidine reacts with acetic anhydride – dependent on reaction conditions – to form mono-, di- or triacetyl-N-methoxyguanidines. The properties of these hitherto not known compounds are described, mass spectra are given.     

Das unterschiedliche massenspektrometrische Fragmentierungsverhalten von Lysinmethylester und dessen N,N′-Diacetylderivat. 27. Mitteilung über das massenspektrometrische Verhalten von Stickstoffverbindungen

The Different Behaviour of Lysine Methyl Ester and its N,N′-Diacetyl Derivative under Electron Impact The base peak in the spectrum of lysine methyl ester is due to the fragment ion C₅H₁₀N (m/e 84), for which the cyclic structure g (Scheme 1) is deduced. During its formation from the [M-COOCH₃]-ion an equilibration of both nitrogen atoms takes place (ion c , Scheme 1). The cyclic nature of ion m/e 84 is in agreement with the intensity of the corresponding ions in the spectra of homologues of lysine methyl ester (Fig. 1). Although in comparison with lysine methyl ester ( 1 ) N,N′-diacetyl-lysine methyl ester ( 7 ) shows the same general fragmentation pathway with formation of the ions [M-COOCH₃] and [M-COOCH₃-H₂NCOCH₃] (m/e 126), the exact fragmentation mechanism proves to the different. Two mechanisms are discussed for the formation of the ion m/e 126 from 7 (Schemes 2 and 3). The results are based on the spectra of labelled derivatives.     

Über die rolle der Aminogruppen der Faser für die Sorption von anionischen farbstoffen: Versuche mit Amino- und Hydroxypolypropylen 15. Mitteilung über textilchemische Untersuchungen [1]

(1) Three anionic mono azo dyes (Orange I, Orange II and Orange 8) and a 1:2 metal complex dye (Cibalan Grey BL) are dyed onto aminopolypropylene. With all the dyes, a Langmuir isotherm with a stoichiometric relation between the dye adsorbed and the concentration of amino groups on the substrate is obtained.     

Notiz zum massenspektrometrischen Zerfall monohalogenierter Essigsäuren und Essigsäureester. 36. Mitteilung über massenspektrometrische Untersuchungen

Note on the Mass Spectral Decomposition of Monohalogenated Acetic Acids and its Esters Besides the well known ester fragmentation reactions two unusual decomposition reactions are observed in the mass spectra of the title compounds, leading to the ions [M-CO₂]⁺ and [M-HX]⁺. The rearrangement reactions involved in the formation of these ions are discussed.     

Substituenteneinfluss bei der massenspektrometrischen Fragmentierung: Untersuchungen an N-methyl-β,β′-diphenyl-diäthylaminen. 19. Mitteilung über das massenspektrometrische Verhalten von Stickstoffverbindungen

Some different substituted N-methyl-β,β′-diphenyl-diethylamines (I) were investigated mass spectrometrically. The main fragmentations and their genesis are summarized in Scheme 2. The molecular ion generates the major fragmentions a (m/e 148) and b (m/e (147 + X)); c (m/e 105) is formed from a and d (m/e (104+X)) from b by further decomposition. The logarithms of the ratios of the relative ion intensities a/b , c/a and d/b were correlated according to the Hammett equation with different substituent constants. The following correlation coefficients (at 20ev) were found: r = 0,98 (σ⁺), r = 0,63 (σ) and r = 0,96 (σ) respectively. On the basis of the above Hammett correlations, the value of this kind of investigation for the elucidation of mass spectral fragmentation mechanisms is discussed.     

Über die Synthese von Verbindungen mit dem Skelett der Homoproaporphine. 7. Mitteilung über natürliche und synthetische Isochinolinderivate

The synthesis of the tetracyclic spiro compounds 11, 12, 13, 14, 17, 18, 19 and 20 with homoproaporphine skeleton is described. Crucial intermediates are the secondary alcohols 10 and 16 . The structure of the spiro compounds is proved by transformation of 11 into the dihydronaphthalene derivative 24 and NMR.-spectroscopic studies of the latter.     

Bildungsenthalpien fester legierungen der binären systeme des eisens, kobalts und nickels mit germanium und zinn

The formation enthalpies of solid alloys in the Fe---Ge, Co---Ge, Ni---Ge, Fe---Sn, Co---Sn and Ni---Sn binary systems have been determined with the aid of a solution calorimeter using liquid tin as solvent. The formation enthalpies exhibit negative and, sometimes, high values. Parameters influencing the magnitude of the ΔH_B values are discussed. Specifically, the effect of charge transfers between the unlike atoms is emphasized.     

Untersuchungen über N-(Methoxycarbimidoyl)guanidin 1. Synthese und spektroskopische Untersuchungen,Reaktion mit Kohlenstoffdisulfid

Studies on N-(Methoxycarbimidoyl)guanidine. 1. Synthesis and Spectroscopic Studies, Reaction with Carbon Disulfide For the first time the title compound MCG (formula see ?Inhaltsübersicht”?) has been isolated as a free base. The conformations in solid state and in solution are derived from infrared, ¹H- and ¹³C-NMR, and mass spectra. In agreement with other guanidines MCG and MCG · HCl show a rapid interchange of amino protons. Out of ¹H-NMR spectra the activation parameters of the interchange processes are estimated only for MCG · HCl (thermolability of MCG). Reaction of MCG with carbon disulfide is coupled with an elimination of the methoxyl group and cyclization to yield the known 4,6-diamino-1,3,5-thiadiazine-2-thione. The reaction is a novel route to synthesize this class of compounds.