Darstellung neuer substituierter 1,2,4-Triazin-6-carbonsäuren und 1,2,4-Triazin-6-yl-alkancarbonsäuren

Synthesis of New Substituted as-Triazine-6-carboxylic Acids and as-Triazine-6-yl-alkanoic Acids New substituted 3-amino-, 5-amino- and 3,5-diamino-as-triazine-6-carboxylic acids 4a , b , 5a , b and 6 were obtained by the hydrolysis 6-azalumazine derivatives 3a – e . Corresponding acids of the structure 10a – d , 11a , b and 12 were synthesized from 5-chlor-3-methylthio-astriazine-6-carboxylic-ester 8 . The synthesis of new 3-alkylthioderivatives of as-triazine-6-yl-acetic acid 16a – c and -propionic acid 18 and its hydrolysis to 3,5-dioxotetrahydro-as-triazine-6-yl-propionic acid 19 is reported.     

Produkte der Dimerisierung ungesättigter Fettsäuren III: Trennung dimerer Fettsäuren mittels GC und HPLC — Nachweis aliphatischer und verzweigter Dicarbonsäuren

Products of the Dimerisation of Unsaturated Fatty Acids III: Separation of Dimeric Fatty Acids with the Aid of GC and HPLC — Identification of Branched Aliphatic Dicarboxylic Acids From dimers produced by dimerisation of pure oleic acid we obtain by freezing small amounts of compounds, which can be separated further by GC. The separated compounds are isomers with a molecular weight of 594. They are saturated branched aliphatic dicarboxylic acid esters. They are obviously produced by en-reaction followed by hydrogenation. A much more effective separation than by GC is possible by HPLC, using a detector based on light scattering. Thus the dimeric fatty esters can be separated into four fractions: the first fraction consists of aromatics, the second obviously of alicyclic and unsaturated dicarboxylic acids, the third and fourth consist of aliphatic dicarboxylic acid esters of MW 594. Fatty acids obtained by dimerisation of a starting material rich in linoleic acid contain large amounts of aromatic compounds, those which are obtained by dimerisation of starting material rich in oleic acid contain rather high amounts of aliphatic dicarboxylic acids and practically no aromatic compounds.     

Oxidatives Verfahren zur Herstellung kurzkettiger Carbonsäuren aus ungesättigten Fettsäuren

Oxidative Procedure for Production of Short-Chain Carbon Acids from Unsaturated Fatty Acids For decades, the oxidation of oleic acid to acelaic and pelargonic acid has been carried out in industrial scale by ozone. The high costs of ozone production are a problematical point in this procedure. Thanks to the high selectivity the procedure is today still economic. Efforts to replace the ozone oxidation by an oxygen one haven't yet led to a procedure which can be applied in industry. In this work the oxygen oxidation of oleic acid with aldehyds as intermediary carrier of oxygen is reported.     

Gaschromatographische und dünnschichtchromatographische Untersuchung von Fettsäuren: Die Anwendung von gepackten Glaskapillarsäulen zur Trennung von cis- und trans-ungesättigten Fettsäuren

Gas Chromatographic and Thin-Layer Chromatographic Studies on Fatty Acids: The Application of Packed Glass Capillary Columns for Separation of cis- and trans-Unsaturated Fatty Acids from Saturated Fatty Acids Packed glass capillary columns were used for the quantitative determination of trans- and cis-unsaturated fatty acids in the presence of saturated fatty acids by gas chromatography. The fatty acids were analyzed as methyl esters after interesterification of the triglyceride samples. The conversion of glyceryl esters of fatty acids into methyl esters could be followed using short GC columns and by thin-layer chromatography.     

Regioselektive C-H-Funktionalisierung von Fettsäuren und Fettsäuremethylestern

Regioselective C-H-Functionalization of Fatty Acids and their Methyl Esters Fatty acids and thier methyl esters can be chlorinated preferentially at the terminal methylene groups with N-alkylchloroamines in sulfuric acid. With capric acid and its methyl ester the optimal reaction conditions for the selective chlorination were elaborated and then transferred to longer fatty acids up to stearic acid. The influence of the solvent, the temperature and the nature of different chlorinating reagents on the selectivity was studies. The capillary GC/MS-analysis of the isomeric chlorinated fatty acids is described.     

Übergangsmetallkatalysierte Oxidationen ungesättigter Fettsäuren — Synthesen von Keto- und Dicarbonsäuren

Transition-metal Catalyzed Oxidation of Unsaturated Fatty Acids — Synthesis of Ketocarboxylic Acids and Dicarboxylic Acids Terminal unsaturated C₁₀–C₁₄-fatty acid methylesters (9-decenoic-, 10-un-decenoic-, 13-tetradecenoic methylesters) were converted to methylketocarboxylic methylesters (yields: 60–75%, isolated) by oxidation with O₂/H₂O at roomtemperature under catalysis of PdCl₂/CuCl₂. Using RhCl₃/FeCl₃ at 80°C yields of 40–60% were obtained. For the first time methyl oleate was converted directly to a mixture of 9-oxo- and 10-oxo-stearic acid methylester by palladium catalyzed oxidation. In DMF/H₂O the selectivity to these two ketoesters was 85% (15% isomers), in dioxane/H₂O the selectivity droped to 55% while the yield of the oxostearic acid esters climbed to 70%. The Mn-catalyzed oxidative cleavage of methylketocarboxylic acid esters with O₂ at 115°C led in each case to a mixture of two dicarboxylic acid esters in a molar ratio of 2 : 1. Starting with 9-oxodecanoic acid azelaic and suberic acid were obtained at a conversion rate of 90%. Analogous 10-oxoundecanoic acid led to C₁₀/C₉- and 13-oxotetradecanoic acid led to C₁₃/C₁₂-dicarboxylic acids. The oxidative cleavage of 9-/10-oxostearic acid methylester yielded mixtures of C₈–C₁₀-monocarboxylic acids and methylesters of C₈–C₁₀-dicarboxylic acids.     

Isolierung und Strukturaufklärung polyverzweigter Fettsäuren aus Fischöl

Isolation and Structure Determination of the Polybranched Fatty Acids from Fish Oil From a sample of sea fish oil, three saturated polymethyl branched fatty acids could be separated in pure state as methyl esters by using urea adduct, column chromatography and distillation methods. These could be identified as 4,8,12-trimethyl-tridecanoic acid, 2,6,10,14-tetramethyl-pentadecanoic acid and 3,7,11,15-tetramethyl-hexadecanoic acid, with the help of molecular weight determination, ultimate analysis, IR-, NMR- and mass-spectroscopy. The structures could be proved by synthesis. Many other branched chain fatty acids were synthesised for comparison. The synthesis and the infrared spectrums of these compounds are given in details.     

Cyclische Konjudien-Carbonsäuren mit einer semicyclischen Doppelbindung aus der Alkali-Cyclisierung langkettiger Triencarbonsäuren

Cyclic Conjugated Dienoic Carboxylic Acids with a Semicyclic Double Bond from Alkali Cyclisation of Long-Chain Trienoic Carboxylic Acids In the alkali cyclisation of 9-cis, 12-cis, 15-cis-octadecatrienoic acid and of 9-cis, 11-trans, 13-trans-octadecatrienoic acid conjugated dienoic carboxylic acids with the structures 9 to 12 are formed in addition to the ω-(2-alkylcyclohexadienyl)carboxylic acids 3 to 8. The formation of these conjugated dienoic carboxylic acids with semicyclic double bond from the corresponding ω-(2-alkylcyclohexa-3,5-dienyl)carboxylic acids (3) is explained by an ionic shift of the conjugated diene system under the action of the base.     

Cyclopentenylfettsäuren im Brennpunkt

Focus on Cyclopentenyl Fatty Acids A Commentary and survey on the nomenclature and configuration of cyclopentenyl fatty acids is given in view of the interest on biologically active compounds derived from such unusual fatty acids. The trivial name alepramic acid is proposed for the C₈-cyclopentenyl fatty acid. Biosynthetic studies suggest Passifloraceae and Turneraceae as potential sources for cyclopentenyl fatty acids in temperate zones.     

Produkte der Dimerisierung ungesättigter Fettsäuren V: Die Aromatenfraktion dimerer Fettsäuren

Products of Dimerisation of Unsaturated Fatty Acids V: The Aromatic Fraction of Dimeric Acids The aromatic fraction of dimeric fatty acid esters can be separated according to a decreasing grade of unsaturation by HPLC using an UV-recorder. Hydrogenation experiments of the collected fractions allowed the determination of the number of rings. If the aromatic fraction are oxidized with KMnO₄ using a phase-transfer catalyst benzene 1,2,4- and 1,3,5-tri-, 1,2,4,5-and 1,2,3,5-tetra- and the pentacarboxylic acid were obtained as main products. Consequently we have to conclude that the catalyst causes intramolecular extensive migration of alkyl chains. Finally 2,3-dihydrobenzofurantetracarboxylic acids with different position of the carboxylic groups were detected in the mixture of oxidation products.     

Über die Reduktion ungesättigter Fettsäuren und deren Ester zu ungesättigten Fettalkoholen durch selektive katalytische Hochdruckhydrierung II: Zur Isomerisierung und Sättigung der Doppelbindungen,Teil 2, Polyensäuren und Ozonisierungsversuche

Reduction of Unsaturated Fatty Acids and their Esters to Unsaturated Fatty Alcohols by Selective Catalytic Hydrogenation under High Pressure II: The Isomerisation and the Saturation of Double Bonds: Part 2, Polyenoic Acids and Ozonization Experiments The side reactions, which take place along with the main reaction during the selective catalytic reduction with hydrogen to corresponding unsaturated fatty alcohols, are studied by investigating the behaviour of definite unsaturated fatty acids. The relationship between the structure of an unsaturated fatty acid and the selectivity of the hydrogenation process carried out in the presence of a special catalyst is studied.     

Über die Reduktion ungesättigter Fettsäuren und deren Ester zu ungesättigten Fettalkoholen durch selektive katalytische Hochdruckhydrierung II: Zur Isomerisierung und Sättigung der Doppelbindungen,Teil 1, Allgemeines und Monoensäuren

Reduction of Unsaturated Fatty Acids and Their Esters to Unsaturated Fatty Alcohols by Selective Catalytic Hydrogenation Under High Pressure II: The Isomerisation and the Saturation of Double Bonds: Part 1, General Information and Monoenoic Acids The side reactions which take place along with the main reaction during the selective catalytic reduction with hydrogen to corresponding unsaturated fatty alcohols, are studied by investigating the behaviour of definite unsaturated fatty acids. The relationship between the structure of an unsaturated fatty acid and the selectivity of the hydrogenation process carried out in the presence of a special catalyst is studied.     

Qualitative und quantitative Untersuchung der freien Fettsäuren in Depotfetten und fetthaltigen Erzeugnissen

Qualitative and Quantitative Investigation of Free Fatty Acids in Depot Fats and Fat-Containing Products The free fatty acids (FFA) in the fat of dry sausages were adsorbed on aluminia. After elution the methylesters of the fatty acids were separated on Reoplex (400). The composition of fatty acids released from fats showed distinct differences to the composition of a fat after saponification. Myristic, palmitoleic and linoleic acid had increased in the amount expressed as percentage of fatty acids while the percentage of stearic and possibly palmitic acid had decreased in concentration. The volatile fatty acids (<14 C) increased in the fat of dry sausages, too.     

Neuartige Imidazoline und ihre Derivate aus Fettsäuren und Hydroxyalkylaminen

Novel Imidazolines and Their Derivatives from Fatty Acids and Hydroxyalkylamines Epoxides, derived from terminal and internal olefins, were reacted with ethylenediamine to give N-(vic.-hydroxyalkyl)-ethylenediamines and condensed with fatty acids and aromatic as well as aliphatic mono- and dicarboxylic acids to give 2-imidazolines. Quaternation of the 2-imidazolines yields imidazolinium salts, which, according to their structure, show strong microbiocide properties; they are also of interest as textile auxiliary.     

Untersuchungen über die Entstehung von Kohlenwasserstoffen in UV-bestrahlten Fettsäuren und Fettsäure-Estern

Studies on the Formation of Hydrocarbons in Fatty Acids and Fatty Acid Esters Irradiated with UV Rays The investigation of volatile compounds in unsaponifiable matter and in steam distillates of UV-irradiated saturated fatty acids and fatty acid esters has shown that by irradiation in the presence of air as well as under vacuum, along with other substances, unsaturated hydrocarbons are formed. They are most probably 1,2 alkenes whose chains are shorter than the corresponding fatty acids by 2 C-atoms. The volatile compounds in the unsaponifiable matter of the UV-irradiated oleic acid comprise predominantly of carbonyle compounds.     

Anionen-grenzflächenaktive Stoffe aus Aminosäuren und Glycidäthern

Anionic Interfacially Active Agents from Amino Acids and Glycid Ethers After referring to the preparation of interfacially active agents by using amino carboxylic acids, especially sarkosine, experiments on the reaction of alkylene oxides as well as glycid ethers with amino carboxylic acids are described. Saturation concentrations, critical micelle concentrations and corresponding surface tensions (dyn/cm) of the aqueous solutions (0° d. H.) at 20° C are given for the adducts from glycine or sarkosine with octylene-1,2-oxide and n-octyl- or lauryl glycid ether.     

Vorkommen bitterer Hydroxyfettsäuren in Hafer und Weizen

Occurrence of Bitter Hydroxy Fatty Acids in Oat and Wheat Water suspensions of oat, soft wheat, and durum wheat flours were incubated for 4.5 h at 38° C. Only the oat flour became intensely bitter. Freeze-dried samples of the incubated flours were analyzed for free hydroxy fatty acids with bitter taste. 750 μg/g L-OH (mixture of 9-hydroxy-trans, cis-10,12-octadecadienoic acid and 13-hydroxy-cis, trans-9,11-octadecadienoic acid) and 62 μg/g Tri-OH (mixture of 9,12,13-trihydroxy-trans-10-octadecenoic acid and 9,10,13-trihydroxy-trans-11-octadecenoic acid) were found in oat flour. Soft wheat flour contained the same amount of Tri-OH as oat flour but only 60 μg/g LOH were detected. Considerable less amounts of both L-OH and Tri-OH (20 μg/g and 15 μg/g respectively) were found in durum wheat flour. The bitter taste of oat flour which has been debittered by extraction of the lipids could be restored by addition of a mixture of 750 μg/g L-OH and 62 μg/g Tri-OH.     

Produkte der Dimerisierung ungesättigter Fettsäuren VI: Untersuchungen zur Kinetik der Bildung dimerer Fettsäuren

Products of Dimerisation of Unsaturated Fatty Acids VI: Kinetic Studies about the Formation of Dimeric Fatty Acids During the dimerisation reaction of a mixture of 60% oleic acid and 40% linoleic acid samples were collected in time intervals. The samples were converted into their dimethylates by diazomethane and separated by thin layer chromatography in one fraction of monomers and one of dimers. The monomeric fractions were further separated by GC, the dimeric fractions by HPLC. First linoleic acid reacts, either by cyclisation or by attacking another molecule of linoleic acid. Thus linoleic acid has already disappeared nearly completely at the end of the heating up period (after 60 min). The less linoleic acid is present, the more molecules of linoleic acid react with oleic acid molecules. The primary cyclic dimerisation products are slowly converted to aromatic compounds as well as cyclohexane derivatives. The oleic acid is transformed already in the heating up period into its isomer, elaidic acid and isomers thereof with double bonds in other positions of the chain. These products are converted slowly partly to stearic acid, partly to isostearic acids. Dimeric compounds of MW 592 (methylates) are produced as well by reaction of 2 molecules of oleic acid. They are slowly converted to open chain dimeric acids of MW 594 (methylates).     

Über die Autoxydation von Linolsäuremethylester in Wasser V: Isolierung und Identifizierung einiger Carbonsäuren mittlerer Kettenlänge

Autoxidation of Methyl Linoleate in Water V: Isolation and Identification of Some Medium Chain Carboxylic Acids From the product of autoxidation of methyl linoleate the following carboxylic acids were isolated and identified as their N,N-dimethyl-p-aminobenzolazophenacyl esters: monomethyl suberate, α-hydroxy oenanthic acid, 4-hydroxy-2-transnonenoic acid, 4-hydroxy-12-carbmethoxy-2-trans-dodecenoic acid, and an ω-carbmethoxy carboxylic acid of unknown chain length.     

NMR- und IR-spektroskopische Bestimmung des Zahlenverhältnisses von Methyl- und Methylengruppen in Kohlenwasserstoffen,Alkoholen, Carbonsäuren und deren Estern. Besonderheiten bei verzweigten Carbonsäuren,Olefinen und cyclischen Verbindungen

NMR- and IR-Spectroscopic Determination of the Ratio Between Methyl and Methylene Groups in Hydrocarbons, Alcohols, Carboxylic Acids and Their Esters. Special Characteristics of Branched Carboxylic Acids, Olefins and Cyclic Compounds A series of typical examples of compounds from various important classes have been studied in order to compare the ratio of methyl to methylene groups (degree of branching) as determined by NMR- and IR-spectroscopy with the theoretical values. Considerable agreement was found in most of the cases, however, deviations were observed with olefins containing internal double bonds, alcohols, α-methyl branched carboxylic acids and aromatic compounds. The main reasons for such deviations were found out by comparative application of the various methods. The advantage of combined application of both the methods is demonstrated in the analysis of technical products.