Metallkomplexkatalysatoren mit Phosphonsäureester-Phosphan-Liganden. I. Carbonylierung von Methanol mit Phosphonsäureester-Phosphan-Rhodiumkomplexen in der Flüssigphase

Metal Complex Catalysts with Phosphonic Ester Phosphine Ligands. I. Carbonylation of Methanol by Phosphonic Ester Phosphine Rhodium Complexes The treatment of technically available 2-(chloroethyl)phosphonic acid dimethylester ( 1 ) with diphenylphosphine and potassium-tert.-butylate affords 2-(diphenylphosphino)ethylphosphonic acid dimethylester ( 2a ) in a simple way. 2a can be used as a hemilabil complex ligand (by phosphine and phosphoryl group.) Rhodium complexes of the type (MeO)₂P(O)CH₂CH₂P(Ph)₂RhL₃ ( 3 ) were obtained from 2a and exhibit excellent catalytic properties in the liquid-phase carbonylation of methanol to acetic acid. Studies on other chelat-ligands did not confirm the exceptional increase of the activity by bisphosphinemonoxyd-ligands and the inhibition of the title reaction by bisphosphine-ligands already published.     

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.     

Die Veränderung der freien Fettsäuren nach Verabreichung von Orotsäure

Change in Free Fatty acids after Ingestion of Orotic Acid The level of free fatty acids in blood-serum of rats after per os and intraperitoneal ingestion of orotic acid was studied. High doses of perorally administered orotic acid was without any action, whereas parenteral application led to a considerable lowering of the free fatty acid level already after 30 min. The latter was proportional to orotic acid concentration in serum. The smallest amount leading to a statistically significant reduction was about 100 mg orotic acid/kg, which was present in orotic acid containing compounds.     

Octadecadiensäuren im Butterfett I. Mitteilung: Die Vorstufen bei der Bildung von 4-cis-Heptenal

Octadecadienoic Acids in Butter Fat I: The Precursors of 4-cis-Heptenal It was found that the creamy smell of butter is due to an aldehyde. Because of this finding, it was investigated as to which unsaturated fatty acids in butter cause the creamy smell after autoxidation. A micro-method for the determination of the position of double bonds in the substances which give rise to 4-cis-heptenal, is described.     

Die Analyse von Raffinationsfettsäuren zur Charakterisierung von Futterölen für Kleintiere

Analysis of Feeding Oils for Small Animals Fatty acids used as feeding oils in small animal keeping are mainly acids, which are obtained as by-products during the neutralisation step of edible fats refining process. However, up to now often products with sub-optimal or even low quality were offered in the market. Therefore, the characterization of feeding oils by means of suitable analytical data becomes more important. Up to now used quality criteria are critically investigated especially considering modern methods of analysis and possible alternatives. Among others a method for determination of oxidized fatty acids is reported.     

Die chromatographische Analyse der Gemische von aliphatischen Dicarbonsäuren und Lactonen

The Chromatographic Analysis of Mixtures of Aliphatic Dicarboxylic Acids and Lactones The separation and identification of 37 aliphatic dicarboxylic acids and lactones have been carried out by means of paper chromatography in three solvent systems and by thinlayer chromatography in one solvent system. On the basis of results obtained and relationships derived, it is possible to identify, without any isolation, the individual dicarboxylic acids and lactones in an unknown mixture of compounds with relative ease. Especially, it is very well possible to separate the cis- from trans-isomer of unsaturated acids and the hydroxy acids. This method has been tested in the analysis of mixtures resulting from γ-irradiated addition of alcohols to maleic acid; the method can be used for the analysis of natural materials.     

Alkylendiamide und Alkylendiisoimide von Äthyleniminocarbonsäuren und -dicarbonsäuren

Alkylenediamides and Alkylenediisoimides from Ethyleneimino Carboxylic Acids and Ethyleneimino Dicarboxylic Acids Preparation and properties of some alkylenediamides from β-ethyleneiminopropionic acid and ethyleneiminosuccinic acid as well as of two alkylenediisoimides of ethyleneiminosuccinic acid are described.     

Die Zusammensetzung tierischer Organ- und Depotfette in Abhängigkeit von der Fütterung II Gas-chromatographische Analyse der Fettsäuren von Kälber- und Rinderfetten

The Composition of Lipids of Animal Organ and Depot Fats in Relation to Feed II: Gas-chromatographic Analysis of Fatty Acids of Calves and Cattle Fats In the milk as well as in the fats of calves and cattle 81 fatty acids were found. The composition of fatty acids of the depot and organ fats of cattle — in winter with stall-feeding and in summer with pasture-feeding — were compared with the winter and summer milk fats. The differences between the fats from the same parts of calves and cattle are discussed.     

Octadecadiensäuren im Butterfett II. Mitteilung: Identifizierung einiger nichtkonjugierbarer Fettsäuren

Octadecadienoic Acids in Butterfat II: Identification of a Few Nonconjugable Fatty Acids With the help of gas and thin-layer chromatography as well as by determining the position of double bonds with OsO₄, the following iso-linoleic acids in the butter fat were identified: cis,trans (or trans,cis): 11, 16 and/or 11, 15; 10, 16 and/or 10, 15; 9, 15 and/or 9, 16; 8, 16 and/or 8, 15 and/or 8, 12. trans,trans: 12, 16; 11, 16 and/or 11, 15; 10, 16 and/or 10, 15; 9, 16 and/or 9, 15 and/or 9, 13.     

Produkte der Dimerisierung ungesättigter Fettsäuren XII: Die Dimerisierung von Konjuensäure

Products of Dimerisation of Unsaturated Fatty Acids XII: The Dimerisation of Conjugated Fatty Acids Dimeric fatty acids obtained by the clay-catalyzed dimerisation of the conjugated fatty acid (mixture of 9,11-octadecadienoic acid and 10,12-octadecadienoic acid) can be separated via HPLC in form of their dimethylates in three fractions in accordance with results obtained by separation of dimeric fatty acids of linoleic acid. The first fraction of aromatic dimeric fatty acids with the molecular weight 586 mainly contains compounds with a tetrasubstituted ring system. The second fraction, consisting of alicyclic unsaturated dimeric fatty acids, is characterized by the molecular weight 590 and a cyclohexene ring system. The third fraction corresponds to alicyclic saturated dimeric fatty acids. Dimeric fatty acids resulting of a Diels-Alder-reaction were detected neither in the end products nor as products in the early phase of the dimerisation. The results obtained by the investigation of the dimerisation of conjugated fatty acids are similar to those of the dimerisation of linoleic acid. Consequently a Diels-Alder-reaction is not involved in the formation of dimeric fatty acids. Although conjugated fatty acids are predominated to undergo a Diels-Alder-reaction no such products could be detected. This result strengthens the thesis that the dimerisation of unsaturated fatty acids is initiated by a cationic mechanism. The composition of the dimeric fatty acid using conjugated fatty acids is more uniform than that of usual mixtures of linoleic and linolenic acid. This provides evidence that a modification of the educt fatty acids can yield new structures of the dimerisation products.     

Gezielte Synthese von Dimerfettsäuren

Selective Synthesis of Dimer Fatty Acids Dimer fatty acids are aliphatic C₃₆-dicarboxylic acids, and are important raw materials for the manufacture of polyamides, polyesters, heavy duty lubrication oils and plasticizers. They are made by condensation of two unsaturated fatty acids in the presence of a catalyst. Because of the complicated reaction mechanism a complex mixture is obtained. Therefore only insufficient information in regard to the structure has been obtained. We report the synthesis of single isomers of linear and branched C₃₆-dicarboxylic acids. Characteristic spectroscopic and GC-data of the structural types are reported.     

Herstellung von Alkylenglykomonoestern durch Alkoxylierung von Carbonsäuren

Preparation of Alkyleneglycol Monoesters by Alkoxylation of Carboxylic Acids A new process of alkoxylation using amines as catalysts is reported for the preparation of alkyleneglycol monoesters of aliphatic carboxylic acids. Prim., sec. and tert. amines act as highly selective catalysts at about 80°C. The monoester contents amount to 85–100%. The formation of diester and polyglycol is almost completely suppressed.     

Die massenspektrometrische Fragmentierung von Neopentylpolyolestern II Trimethylolpropantrifettsäureester

Mass Spectrometric Fragmentation of Neopentylpolyolesters, Part II: Fatty Acid Triesters of Trimethylolpropane The fragmentation of the homologous fatty acid triesters of trimethylolpropane (C₂ to C₁₄) upon electron impact was investigated. Main fragments arise by M–RCOO and M–RCOOH. Cyclic acetal structures for these ions are postulated. Subsequent fragmentation was elucidated by DADI-measurements and high resolution measurements. The influence of the length of the fatty acid chain upon the fragmentation is discussed. Esters of branched fatty acids can be distinguished from esters of n-fatty acids by characteristic ions.