Montanari modification

With regards to the mechanism of the generation of onium anion, the Starks extraction mechanism and interfacial mechanism (Brandstrom-Montanari modification) are suggested (Scheme 1.7). As in the above-described case, the interfacial mechanism seems to be operative in the asymmetric phase-transfer catalysis. 

Starks Extraction Mechanism Brandstrom-Montanari Modification... 

FIG. 2 Brandstrom-Montanari modification of Starks extraction mechanism for simple phase-transfer-catalyzed displacement reaction. 

If the catalyst is highly organophilic, it can be present exclusively in the organic phase and still be a good PT catalyst. Brandstrom-Montanari (Brandstrom, 1977 Landini et al. 1977) modification to the extraction mechanism is more appropriate (Figure 16.2b). Here, ion exchange takes place at the interface of the two phases and not in the aqueous phase. Thus, partitioning of the quat between the two liquid phases is not a necessary condition for effective phase-transfer action in liquid-liquid systems. 

Gandini A, Naceur BM, Guo ZX, Montanari S (2002) Lignins as macromonomers for polyesters and polyurethanes. In Hu TQ (eds) Chemical modification, properties, and usage of lignin. Academic/Plenum, NY, pp 57-80... 

Montanari G.C., Fabiani D., Palmier F., Modification of electrical properties and performance of EVA and PP insulation through nanostructure by organophUic silicates , IEEE Transactions on Dielectrics and Electrical Insulation 2004 11 (5) 754-762. Wu C.L., Zhang M.Q., Rong M.Z., Friedrich K., Tensile performance improvement of low nanoparticles filled-polypropylene composites , Composites Science and Technology, 2002 62 1327-1340. 

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