Zum Reaktionsmechanismus von Glutaraldehyd mit Proteinen

The interaction of glutaraldehyde with model aliphatic amines was studied in order to understand the crosslinking reaction of glutaraldehyde with proteins. The reaction in organic solvents gave N-alkyl-1,4-dihydropyridines and N,N-dialkyl-1,5-diiminopentanes. The isolated products are new or were previously described by us for the first time¹. Hydration of the reaction products led to stable N-alkylpiperidines and N,N-dialkyl-1,5-diaminopentanes. In aqueous solution the reaction depends on thepH: at apH above 7, N-alkyl-1,4-dihydropyridines and at apH below 7, polymers were obtained. For the crosslinking reaction of proteins with glutaraldehyde the following mechanism is proposed: Monomeric glutaraldehyde reacts with the protein to give intermediate N-alkyl-2,6-dihydroxypiperidines. Intramolecular dehydration leads to the corresponding N-alkyl-1,4-dihydropyridines. Condensation of the cyclic monohydrate of glutaraldehyde and N-alkyl-2,6-dihydroxypiperidines gives linear polymeric crosslinks containing -oxo-N-alkylpiperidine units.

Lubig R., Dissertation, RWTH Aachen, 1974.     

Zum oxydativen Abbau von elementarem Phosphor,P4, mit CCl4 und 1,2-Dinucleophilen

On the Oxidative Degradation of Elemental Phosphorus, P₄, with CCl₄ and 1.2-Dinucleophiles In the presence of tertiary amins the interaction of elemental phosphorus with CCl₄ and bifunctionally protic nucleophiles such as 1.2-dioles, pyrocatechol, and 2-aminoalcohols leads to an oxidative degradation of P₄. Depending on the reaction conditions acyclic as well as cyclic and even spirocyclic phosphorus(III) and phosphorus(V) compounds are obtained in variable proportions. The formation of the phosphorus(V) spiro compounds exclusively occurs by oxidizing spirocyclic phosphorus(III) compounds in the way of the Atherton-Todd reaction. A procedure for preparing triethylammonium tris(o-phenylenedioxo)phosphate, 8 , directly from P₄, CCl₄, and pyrocatechol is given.     

Nachweis von geringen Mengen HCl durch Reaktion von 7-Oxabicyclo-(4.1.0)-heptan mit HCl

Summary This paper the possibility of determining small quantities of HCl by derivatization with 7-oxabicyclo-(4.1.0)-heptane and subsequent gas chromatographic identification of the reaction product 2-chlorocyclohexanol is examined. The detection limit for the derivative (2-chlorocyclohexanol) is equivalent to 2 pg HCl. On account of various problems, discussed in the paper, this detection limit is not achieved in practice. It is nevertheless apparent that concentrations of HCl in the ppm-region (quantities of HCl<1 μg) can be determined without difficulty. The scope for this method of analysis is disscussed.

---

Nachweis von geringen Mengen HCl durch Reaktion von 7-Oxabicyclo-(4.1.0)-heptan mit HCl

Zusammenfassung In der vorliegenden Arbeit wird die M?glichkeit untersucht, kleine Mengen HCl durch derivatisierung mit 7-Oxabicyclo-(4.1.0)-heptan und anschlie?endem gas-chromatographischen Nachweis des Reaktionsproduktes 2-Chlorcyclohexanol zu bestimmen. Die Nachweisgrenze für das Produkt der Derivatisierung (2-Chlorcyclohexanol) entspricht 2 pg HCl. Durch verschiedene Probleme, die im Rahmen dieser Arbeit diskutiert werden, wird diese Nachweisgrenze in der Praxis nicht erreicht. Es zeigt sich jedoch, da? HCl-Konzentrationen im Bereich von ppm (bzw. HCl-Mengen<1 μg) ohne weiteres zu bestimmen sind. Die M?glichkeiten dieser Analysenmethode werden diskutiert.

     

Reaktion von primären Alkylhydroperoxiden mit Amidoschwefelsäurechlorid: Alkyl(amidosulfonyl)peroxide

The novel peroxides H₂NSO₂OOCH₂ R (1 a:R=CH₂CH₃;1 b:R=CH₂CH₂CH₃) are obtained by reaction of sulphamoyl chloride with the appropriate hydroperoxides in the presence of pyridine (temperature below –30 °C, solvent diethyl ether). The solvent-free liquids1 deflagrate at ca. 0 °C. Hydrolysis or ammonolysis of1 generates the hydroperoxide and sulphamic acid or sulphamide, respectively. Controlled thermolysis of1 affords sulphamic acid and carbonyl compounds, i.e. propanal andn-propyl propanoate from1 a, butanal, 2-methylpropanal andn-butyln-butyrate from1 b. These products suggest a nonradical cyclic decomposition path-way.

     

Konformationsanalyse von Gallenfarbstoffen mit Hilfe von Kraftfeldrechnungen

A force field constructed for bile pigments and parametrized on partial structures of bile pigments was used to calculate the minimum energy geometries of diastereomeric bilatrienes-abc. In addition the relative energies of these isomers were deduced and the energies of interconversion between the mirror images of the more or less helical (Z,Z,Z)-syn, syn, syn-form were calculated for various paths.

     

Zum Abbau von polycyclischen aromatischen Kohlenwasserstoffen

Zusammenfassung Polycyclische aromatische Kohlenwasserstoffe (PCA) können unter den in der vorliegenden Arbeit angewendeten Reaktionsbedingungen, nämlich niedrige PCA-Konzentrationen und hoher Ozon-Überschuß, nicht zu Kohlendioxid und Wasser abgebaut werden. Als Hauptreaktionsprodukte treten bei linearanellierten PCA Chinone bzw. Chinoncarbonsäuren auf, bei orthoanellierten PCA Biphenylcarbonsäuren. Wichtige Nebenprodukte sind Oxalsäure und, von zwei begründeten Ausnahmen abgesehen, Phthalsäure; in einigen Fällen werden Benzoltetracarbonsäuren gefunden.

---

On the degradation of polycyclic aromatic hydrocarbonsI. Reaction products of the ozonolysis of polycyclic aromatic hydrocarbons in aqueous systems

Summary Polycyclic aromatic hydrocarbons (PCA) cannot be degraded into carbon dioxide and water by ozone, even if, as described in this paper, low concentrations of PCA are treated with a large excess of ozone. The main products of linear anellated PCA are quinones and/or quinone carboxylic acids. In case of ortho anellated PCA, biphenyl carboxylic acids are formed. By-products of interest are oxalic acid and, disregarding two justified exceptions, phthalic acid; in some cases benzene tetracarboxylic acids are present.

     

Umsetzung von Metall- und Metalloidverbindungen mit mehrfunktionellen Molekülen, 22. Mitt.: Die Reaktion von Trimethylsilylcarbonsäureamiden mit Halogen(diorganyl)boranen

Trimethylsilylacetamide and trimethylsilyltrifluoroacetamide react with halogenodiorganylboranes to monomeric or dimeric amidoboranes depending on the organyl substituents. The compounds were characterized analytically and spectroscopically (NMR:¹H,¹⁹F,¹¹B; MS; IR).

21. Mitt.:A. Meller, W. Maringgele, K. Hennemuth undU. Sicker, J. Z. anorg. allg. Chem., im Druck.     

Zur Reaktion von Hydrazinen mit Fluorsilanen und lithiierten Aminen

Lithium salts of hydrazines react with fluorosilanes under formation of fluorosilylhydrazines and LiF. Five membered rings are obtained in the reaction of bis(fluorosilyl)-hydrazines with lithiated amines. The mass,¹H-and¹⁹F-nmr spectra of the compounds are reported.

     

Zur Reduktion von Kaliumacetat und Kaliumpropionat mit Lithiumaluminiumhydrid in Gegenwart von Phasentransfer-Katalysatoren

Ethyl alcohol and propyl alcohol can be prepared with good yields from potassium carboxylates by the reduction with lithium aluminium hydride in the presence of different phase transfer catalysts.

     

Cyclisierung von Oligomeren des Malodinitrils mit Amidinen Synthesen mit Nitrilen, 55. Mitt

Condensation of formamidine-acetate with dimeric malononitrile (1 a) leads to 2,4-diamino-3,5-pyridine-dicarbonitrile (3 a), with acetamidine-HCl the methyl derivative3 b is obtained. Reaction of the codimer of malononitrile and methyl cyanoacetate (1 b) with formamidine yields the aminopyridine3 c, while acetamidine and benzamidine, resp. with1 b react to the 1,4-dihydro-4-pyrimidinylidene-methyl-cyanoacetates4 a-b.

     

Die Reaktion von 7,14-Cyclo-7,8-dihydrocodeinon mit Diazomethan

Reaction of 7,14-cyclo-7,8-dihydrocodeinone (1) with diazomethane gives a mixture, from which nine compounds were isolated; the structures of seven (4a–c, 5, 6, 7a and8) could be determined. Insertion of a methylene group between carbon atoms 5 and6 of1 leads with opening of the ether bridge to7a as the major product.

Herrn Univ.-Prof. Dr.G. Zigeuner mit den besten Wünschen zum 60. Geburtstag gewidmet.     

Beiträge zum thermischen Verhalten von Sulfaten. XVI. Zum chemischen Transport von Ga2(SO4)3 mit Cl2 und mit HCl. Experimente und Modellrechnungen

Contributions on the Thermal Behaviour of Sulphates. XVI. The Chemical Vapour Transport of Ga₂(SO₄)₃ with Cl₂ and HCl. Experimental Results and Calculations Crystals of anhydrous Ga₂(SO₄)₃ can be grown by means of CVT (e. g. 525°C → 475°C) in the less hot region of a closed silica ampoule. We investigated the dependance of the deposition rate on the concentration of the transport agent (Cl₂, HCl) and the transport temperature (475°C ≤ T ≤ 750°C; T₂ > T₁; ΔT = 50°C; T = 0.5(T₁ + T₂)). Experimental results and thermodynamic calculations on the basis of Δ_FH ${}_{\text{298}}^{\text{º}}$ (Ga₂(SO₄)₃) = ?686.5 kcal/mol show a good agreement.     

Zum Reaktionsverhalten von 2,4-Dioxohexahydro-1,3,5-triazin

Summary 2,4-Dioxohexahydro-1,3,5-triazin (DHT) reacts with formaldehyde and secondary amines (Mannich reaction) to the corresponding 1,3,5- or 1,5-aminomethyl-DHTs (1a–8a or1b–11b).DHT and formaldehyde give the methylol compounds12a,12b, and12c. Alkylation ofDHT with alkyl halides in presence of base and dimethyl-sulfoxide as the solvent affords the tri-N-alkyl derivatives14–22. 1,5-Dimorpholinomethyl-DHT (1b) can be alkylated in position 3 with alkyl halides. The morpholinomethyl groups in positions 1 and 5 behave as protecting groups and are easily removable. Thus, it is possible to introduce different alkyl substituents into the molecule. The reaction of1b with dihaloalkanes results in a coupling of twoDHT moleculesvia the nitrogen in position 3 (compounds26–29).

Herrn Professor Dr. mult.Friedrich Asinger zum 90. Geburtstag gewidmet     

Beiträge zum thermischen Verhalten von Sulfaten. XII. Zum chemischen Transport von In2(SO4)3 mit Cl2 und mit HCl. Experimente und Modellrechnungen

Contributions on the Thermal Behaviour of Sulfates XII. The Chemical Vapour Transport of In₂(SO₄)₃ with Cl₂ and HCl. Experimental Results and Calculations By means of CVT (T₁ between 500°C and 825°C; ΔT = 50°C), well shaped crystals of anhydrous In₂(SO₄)₃ can be grown in the less hot region of a closed silica ampoule. We investigated the dependence of the deposition rate on the variation of the concentration of the transport agent (system In₂(SO₄)₃/Cl₂) and on the variation of the transport temperature (In₂(SO₄)₃/Cl₂ as well as In₂(SO₄)₃/HCl). A comparison of the experimental results with thermodynamical calculations shows a satisfying agreement. The influence of the variation of some additional parameters (H₂O from the wall of the ampoule; Δ_BH(In₂(SO₄)₃)) on the deposition rate is discussed.     

Beiträge zum thermischen Verhalten von Sulfaten. XIII. Zum chemischen Transport von Cr2(SO4)3 mit Cl2 und mit HCl. Experimente und Modellrechnungen

Contributions on the Thermal Behaviour of Sulfates. XIII. The Chemical Vapour Transport of Cr₂(SO₄)₃ with Cl₂ and with HCl. Experiments and Calculations Well shaped crystals (cubical or rectangular parallel-epiped respectively, edge length up to 1 mm) of rhombohedral Cr₂(SO₄)₃ can be grown in the less hot zone of a closed silica ampoule by means of CVT using Cl₂ or HCl as transport agents in endothermal transport reactions. The influence of the mean transport temperature as well as the concentration of the transport agents on the deposition rates was investigated. On the basis of thermochemical calculations an explanation of the transport mechanism is given in the present paper.     

Über die Umsetzung von Dibenzylidensulfamiden mit Aminen

Addition of amines to dibenzylidene sulfamide1 a yields the correspondingSchiff bases3 a, b and monobenzylidene sulfamide2. Reaction of several dibenzylidene sulfamides1 with various lithium-amides gives N¹-substituted N²-benzylsulfamoyl-benzamidines7 a-k via an intramolecular hydride transfer reaction, whereas by treatment of1 a with sodium amide 2-benzyl-3,5-diphenyl-3,4-dihydro-2H-1,2,4,6-thiatriazine-1,1-dioxide8 is obtained, which on hydrolysis yields9 and11. Alkylation products are described, the isomeric products12a/13a and12b/13b are isolated, their structures are confirmed by synthesis, IR and NMR-spectra.

     

Zur Synthese von Norbornanonen mit geminaler Dimethylgruppe

The synthesis ofgem-dimethylnorbornanones is described. One synthetic pathway after aDiels-Alder reaction involves the transformation of the nitro group into the oxo group with subsequent methylation into the geminal dimethyl product. A shorter way by [4+2]-cycloaddition of cyclopentadiene with a suitable dimethylated dienophile (e.g. 2-methyl-1-nitropropene) failed, probably by steric hindrance of the dienophile. 7-Oxanorbornanones, with agem-dimethyl group could not be prepared. A second synthetic approach togem-dimethylnorbornanones is opened byLewis acid catalyzed rearrangement of cyclohexenylcarbaldehydes.

Herrn Univ.-Prof. Dr.K. Kratzl mit den besten Wünschen zum 65. Geburtstag gewidmet.