Carefully selected fatty acids allow esters to be composed which, additionally, have excellent polymerization stabdity (Table 9). Polymerization and in the final resort, carbonization are undesirable reactions occurring when unsaturated oils are exposed to air and heat. Viscosity increases until finally rubber-like films are built up which tend to stick very tightly to solid surfaces and which cannot be removed by any solvent. Polymerization-stable substances are of outstanding importance in the composition of high-quality release agents and bread cutting oils or emulsions.
K u r . o $ r and Dr. WMori& for advice and aid in physico-chemical measurements and Dagmar Gobels, Ulrich Haas and Damian Slaps for technical assistance.Etheralcohols (polyols), which are ofinterest inanumberoffieldsofapplication such as, e. g.,PU foams,PU dispersions and PU casting resins,are readily accessible by the acid-catalyzed conversion ofepoxidized fatty materials with mono-and polyvalent alcohols. By means of epoxidized triglycerides and epoxidized oleyl alcohol it is exemplified how polyols with a wideley variable hydroxyl value can be built up by variation ofthe reaction course or the alcohol component. Two selected fields of application are illustrated in more detail.
Hexafluorisopropy1iden)vinylamine 1 reagieren rnit Phosphinen 2 zu Phosphoranen 4. Die Umsetzung von 1 rnit Phosphiten 5 verlauft iiber eine Phosphoranzwischenstufe 6 unter 0 -+ N-Alkylwanderung, die rnit einer Protoneniibertragung konkurriert, zu den Phosphonsaureestern 7 und 8. Der Reaktionsmechanismus, sowie die spektralen Daten der neuen Verbindungen werden diskutiert. Addition of Phosphines and Phosphites to (Hexafluoroisopropy1idene)vinylamines 1) (Hexafluoroisopropy1idene)vinylamines 1 react with phosphines 2 to yield phosphoranes 4. Reaction of 1 with phosphites 5 proceeds via a phosphorane intermediate 6 with an 0 + Nalkyl shift, in competition with a H-shift, to produce the phosphonates 7 and 8. The reaction mechanism and spectral data of the new compounds are reported. lm Rahmen unserer Arbeiten iiber Synthesez) und Reaktionen3) von trifluormethylsubstituierten (Methy1en)vinylaminen 1 haben wir deren Reaktionsverhalten gegenuber Phosphinen und Phosphiten untersucht4). Reaktion von 1 rnit Phosphinen 4-Monosubstituierte (Hexafluorisopropyliden)vinylamine 1 reagieren rnit Phosphinen 2, in einer fur elektronenarme Doppelbindungssysteme typischen Reaktion 5 ) , zu den [I : 11-Addukten 4. Die 31P-NMR-Daten der Verbindungen 4 zeigen negative Werte fur die chemische Verschiebung des Phosphors. Die Signale liegen in einem Bereich, der fur Phosphorylide als charakteristisch angegeben wird6). Intensive 1R-Absorptionen werden fur die Verbindungen 4 im Doppelbindungsbereich bei 1560 -1565 cm-1 beobachtet (a-Carbonylylide absorbieren im Gebiet von 1540 bis *) Korrespondenz bitte an diesen Autor richten. 1) 4. Mitteilung; 3. Mitteilung: Lit.4). -K . Burger, auszugsweise vorgetragen beim 6.
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