Organic polymers, as supports

Modified Organic Polymers as Supports for Mo Oxidation Catalysts Docking entity in polymer Mo catalyst precursor Reference... 

Inorganic polymers have been used less often than organic polymers as supports for immobilized metal complex catalysts, although the better physical properties of the former in general more than compensate for the better chemical properties... 

Chandrasekhar, V. and Athimoolam, A. (2002) New hybrid inorganic-organic polymers as supports for heterogeneous catalysis a novel Pd(0) metalated cyclophosphazene-containing polymer as an efficient heterogeneous catalyst for the Heck reaction. Org. Lett., 4, 2113-6. 

M. J. Frechet, Tetrahedron 37, 663-683 (1981), Synthesis and Applications of Organic Polymers as Supports and Protecting Groups . 

J. M. J. Frechet, Synthesis and applications of organic polymers as supports and protecting groups. Tetrahedron 1981, 37, 663-683. 

Another adaptation of the NMR tedmique involves the measurement of the chemical shift of e adsorbed in a sample. The recent development of this last technique has mainly been concerned with the study of the porous structure of microporous materials such as zeolites [81,82], mesoporous silica [11,83], chlat-rates [84], organic polymers and supported metal catalysts [82]. e is an inert... 

Metal Species Supported on Organic Polymers as Catalysts for the Epoxidation of Alkenes Ulrich Arnold ... 

The subject of soluble polymers as supports in catalysis has been discussed in a number of recent reviews [ 1-5]. These other reviews each focused on a particular polymer or groups of polymers or on some aspect of catalysis (e.g., organic catalysis or asymmetric synthesis) [2, 3, 6-8]. Soluble polymers use as supports in synthesis has also been reviewed, but this topic is not covered below because in synthesis the polymer is used in a stoichiometric amount and is generally not recyclable [5,9-11]. This review takes a general approach, focusing on soluble polymers used as catalyst supports. It discusses these supports within a context of the separation strategies that could be or were used to separate or recover the soluble polymer-bound catalyst from the products. This review emphasizes examples from the last few years where soluble polymers are used but includes, for completeness, earlier examples if a particular... 

Since he was working in an institute for organic chemistry and biochemistry, he was familiar with the work of the Israeli s Katchalski-Katzir and Patchornik, who used polymers as supports for enzyme immobilization and for performing reactions on functional polymers. It was also the time when the mechanism of chymotrypsin was elucidated. This led Wullf to contemplate the possibility of producing synthetic polymers with catalytic sites that worked in the same way as enzyme active sites. There was already some literature on using synthetic polymers as catalytic models of enzymes but these did not have specific structural binding sites as enzymes did. Clearly a new approach would be required to generate such sites with specific predetermined structure. 

As a result of the impetus provided by Merrifield s work with peptides and subsequent work with nucleotides and saccharides, many reports of the use of polymers as supports in general organic chemistry have appeared. In addition to the usual advantages associated with the use of polymeric supports, they offer the possibility of isolating molecules from each other on the polymer matrix. The isolation of one molecule from another on the matrix (the site-isolation or hyperentropic factor) opens the possibility that intramolecular reactions would be the preferred reactions where intramolecular alkylation or acylations were being done. 

Just as for polymer-supported catalysts [9], small proUne-containing peptides have been supported on mesoporous materials as well [54]. As for systems founded on organic polymers, silica-supported systems can also give high catalytic selectivity and activity, and can also be successfully recycled. 

Figure 5.6 Schematic representation of the classical methods for immobilization of chiral catalysts using organic polymers as the supports.

CHEOPS is based on the method of atomic constants, which uses atom contributions and an anharmonic oscillator model. Unlike other similar programs, this allows the prediction of polymer network and copolymer properties. A list of 39 properties could be computed. These include permeability, solubility, thermodynamic, microscopic, physical and optical properties. It also predicts the temperature dependence of some of the properties. The program supports common organic functionality as well as halides. As, B, P, Pb, S, Si, and Sn. Files can be saved with individual structures or a database of structures. 

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