Neue Ergebnisse der Organozinn‐Forschung

Abstract

Es wird eine Übersicht über den gegenwärtigen Stand der Organozinn-Forschung gegeben. Zahlreiche neue, teilweise hier erstmals mitgeteilte Synthesen erlauben es, eine Fülle interessanter Verbindungen herzustellen. Auf einige neue Anwendungsmöglichkeiten von bestimmten Typen von Organozinn-Verbindungen wird hingewiesen. Besonders aussichtsreich erscheint die Verwendung im Pflanzenschutz.Einleitung Die Kohlenstoff-Verbindungen der Metalle der vierten Hauptgruppe des Periodensystems müssen zu den stabilsten Organometall-Verbindungen überhaupt gerechnet werden. In diesen metallorganischen Verbindungen ist die Metall-Kohlenstoff-Bindung verhältnismäßig inert, sowohl gegen hydrolysierende als gegen oxydierende Einflüsse. Dementsprechend sind, im Gegensatz zu den meisten anderen metallorganischen Verbindungen, die organischen Derivate der Elemente der vierten Hauptgruppe zu Alkylierungen oder Arylierungen nur wenig geeignet.Diese hohe Stabilität hängt zusammen mit der in dieser Hauptgruppe immer wieder auftretenden Hybridisierung der s-und der p-Elektronenbahnen in der Valenzhülle zu der tetraedrischen sp 3 -Konfiguration. Hierdurch haben in dieser Hauptgruppe alle Verbindungen vom Typus R 4 M in großen Zügen übereinstimmende physikalische und che-*) Erweiterte Fassung eines Vortrags, gehalten am 28. November 1957 auf der Vortragstagung "Organozinn-Verbindungen des Zinn-Informationsbüros (Düsseldorf) in Frankfurt/Main.

Reactions of Organotin Compounds: I. The Stability of Dimethyltin Dihydride, and Additions to Some Fluoro-Olefins

“…After 45 hours, decomposition was complete, the products being trimethyltin hydride (.%.7y0), hexamethylditin (6.1y0), metallic tin (39%), and hydrogen (-60%) containing a small quantity of methane. These results are consistent with decomposition according to the equation 3(CH3)zSnH2 -+ 2(CH3)3SnH + Sn + 2H2 [I] followed, to a lesser extent, by the reaction 2(CH3)3SnH -t (CH3)sSnz + Hz.…”

“…In the presence of ultraviolet radiation, it therefore appears that two reactions take place, reaction [I] and 2(CH3)2SnHz -+ (CH3)4Sn + Sn + 2Hz. [3] Over long periods of time (40 hours) further decomposition occurs to form hexamethylditin, so that reactions [I], [2], and [3] are all involved. For appreciable decomposition of dimethyltin dihydride, a high temperature is necessary, since a sample exposed to ultraviolet light for 40 hours a t 2.…”

Organotin Compounds: Perspectives and Potential

“…193 Tricyclopentyl-and tricyclohexyltin acetate, however, were more active than the n-alkyl derivatives. 194 Triphenyltin acetate had about the same activity as triethyltin acetate. Tri-m-tolyl-and tri-p-tolytin acetate differed little from triphenyltin acetate, but tribenzyl-and tris (2-phenylethyl) tin acetate were somewhat less active.…”

“…Tri-a-naphthyltin acetate, probably because of its low solubility, did not show any antifungal activity. 194 When, through the addition reactions of organotin hydrides to olefins, functionally substituted organotin compounds became available, a number of them, both of the type R,Sn and R 3 EnX, were tested for antifungal activity. It turned out, however, that in no case did a functionally substituted compound have a higher activity than a comparable unsubstituted compound.…”

Toxicity and health effects of selected organotin compounds: a review.

“…compounds have also been used as stabilizers in certain plastics from which tubings or films for wrapping food are made (13) and have found a number of other industrial uses (14). Of the aryltin compounds, the triphenyltin compounds were suggested in the 1960's as chemosterilants for insects (15)(16).…”