The notion of "green chemistry" has encouraged even synthetic organic chemists to include water as a solvent. Incredible selectivities and activities can be achieved through the addition of amphiphiles with a defined structure. The morphology of supramolecular assemblies or associates formed by surfactants vary according to the temperature and concentration. As a rule, reactions are typically conducted using simple spherical aggregates, that is, micelles in the nanometer range. The strong polarity gradient present between the hydrophilic surface and the hydrophobic core of the micelle means that both nonpolar and polar reagents can be solubilized. This solubilization results in reactants becoming more concentrated within the micelle than in the surrounding water phase and leads to an acceleration of the reaction and causes selective effects. The kinetic treatment of reactions in micellar systems can be accomplished by considering them as microheterogeneous two-phase systems.

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Die Vorstellung einer “grünen Chemie” hat selbst den präparativ arbeitenden Organiker ermutigt, Wasser als Lösungsmittel in Betracht zu ziehen. Durch Zusätze von Amphiphilen bestimmter Struktur kann man erstaunliche Aktivitäten und Selektivitäten erzielen. Die von den Tensiden gebildeten Assoziate variieren in ihrer Morphologie je nach Temperatur und Konzentration. In der Regel arbeitet man im Bereich einfacher sphärischer Aggregate, der nanometergroßen Micellen. Da in Micellen ein starker Polaritätsgradient von der hydrophilen Oberfläche zum hydrophoben Kern vorliegt, können sowohl unpolare als auch polare Reaktanten solubilisiert werden. Dadurch kommt es oft im Vergleich zur umgebenden Wasserphase zu einer Konzentrierung der Reaktionspartner und damit zu einer Beschleunigung der Reaktion. Darüber hinaus treten selektive Effekte auf. Micellare Systeme können kinetisch als mikroheterogene Zweiphasensysteme behandelt werden.

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Oligomeric and polymeric polyether polyols, especially poly(propylene oxide), are used for the production of detergents, nonionic surfactants, washing agents, and cleaners, but they are predominantly used in polyurethane production processes. Tin phosphate coordination polymers show good activity in the selective polymerization of epoxides. The catalyst can be easily synthesized by the condensation of tributyl phosphate and butyl tin trichloride. Investigations of this achiral organotin phosphate condensate in the stereoregular polymerization of propylene oxide, including the properties controlling the molecular weight of the resulting poly(propylene oxide) and structural and mechanistic studies, are presented. Additionally, the polymerization of propylene oxide occurs with high activity, no allyl end groups, just a small number of irregularities, and a high percentage of isotacticity (88%) in the polymer. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3032–3041, 2007

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