Catalysis supported

B. Clapham, T.S. Reger and K.D. Janda, Polymer-supported Catalysis in Synthetic Organic Chemistry, Tetrahedron 57 4637-4662 2007. 

This review has shown that the analogy between P=C and C=C bonds can indeed be extended to polymer chemistry. Two of the most common uses for C=C bonds in polymer science have successfully been applied to P=C bonds. In particular, the addition polymerization of phosphaalkenes affords functional poly(methylenephosphine)s the first examples of macromolecules with alternating phosphorus and carbon atoms. The chemical functionality of the phosphine center may lead to applications in areas such as polymer-supported catalysis. In addition, the first n-conjugated phosphorus analogs of poly(p-phenylenevinylene) have been prepared. Comparison of the electronic properties of the polymers with molecular model compounds is consistent with some degree of n-conjugation in the polymer backbone. 

Examples of fluids confined In pores and spaces of molecular or nanometer dimensions abound In technological and natural products and processes. These Include wetting and lubrication, zeolite supported catalysis, silica gel based chromatrographlc separations, drying of paper... 

Recently, it has been shown that ultrasonic agitation during hydrogenation reactions over skeletal nickel can slow catalyst deactivation [122-124], Furthermore, ultrasonic waves can also significantly increase the reaction rate and selectivity of these reactions [123,124], Cavitations form in the liquid reaction medium because of the ultrasonic agitation, and subsequently collapse with intense localized temperature and pressure. It is these extreme conditions that affect the chemical reactions. Various reactions have been tested over skeletal catalysts, including xylose to xylitol, citral to citronellal and citronellol, cinnamaldehyde to benzenepropanol, and the enantioselective hydrogenation of 1-phenyl-1,2-propanedione. Ultrasound supported catalysis has been known for some time and is not peculiar to skeletal catalysts [125] however, research with skeletal catalysts is relatively recent and an active area. 

Selected Examples for Dendritic Polymer-supported Catalysis (see Tab. 7.2)... 

I 8 Carbonyl Compounds as Metallic Precursors of Tailored Supported Catalysis... 

For general overviews on polymer-supported catalysis, see a) Chiral Catalyst Immohilization and Recycling (Eds. D. E. DeVos, I. F. ). Vankelecom,... 

In this paper the term electronics is used with a different connotation it stands for the description of electron transitions to and from, as well as within supported catalysts. It will be shown that in many cases such transitions are responsible for the enhanced or reduced catalytic activities of supported catalysis. In this concept, supported catalysts are described as solid state systems in which a catalytically active component (the... 

Under conditions that support catalysis, a time-dependent loss of enzyme activity is observed. 

What types of polymeric structures, other than proteins built from the standard 20 amino acids, might support catalysis in water For example, can 2-amino-2-methyl-carboxylic acids, which have been found to be enantiomerically enriched in meteorites, be the basis for a catalytic system In the absence of biopolymers, would selected monomers provide catalysis sufficient to sustain life ... 

What kinds of polymeric structures (or monomer collections) might support catalysis and genetics in nonaqueous environments, particularly in solvents found on solar system bodies other than Earth ... 

Alternative amino acids are easily conceived, both in theory and from experiment. Many alternative amino acids are known in meteorites (Figure 4.5). Several classes, including alpha-methylamino acids, form secondary structures more easily than do standard terran amino acids. Little is known, however, about the ability of polymers built from them to support catalysis. 

Another application of the rearrangement in dendrimers focuses on the development of novel polythioether dendrons on a solid support for supported catalysis applications [94]. 

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