Molecular catalysis enzyme mimics

It has long been established that Pt is the most efficient singlemetal electrode for the catalysis of both reactions (1) and (2). In the case of ddiydrogen activation, no metal electrocatalyst performs better than platinum. However, aside from the fact that platinum is a precious metal, a major drawback is that commercial (fossil-based) hydrogen contains residual amounts of impurities (e g., carbon monoxide) that only serve to poison the catalyst surface." To address this particular problem, present research has focused on the employment of metal additives (e.g., Ru) or of molecular catalysts that mimic the impressive activity of biological materials (e g., hydrogenase enzymes) " the use of molecular catalysts appears to be the more attractive option since such com-... 

In addition to studies where the nature of the recognition events per se has been the major issue, a number of application areas have been explored for imprinted matrices viz. (A) Chromatography, where the imprinted polymer is used as the stationary phase for separation and isolation (Chapter 20). This application is based on the fact that the imprinted polymer has a better retention for the template molecules than others. A related area of application is solid-phase extraction, where the imprinted polymer is used as a sponge to concentrate the molecule of interest (Chapter 23). (B) Immunoassay-type analyses in which molecularly imprinted polymers are used as antibody and receptor mimics (Chapter 25). (C) Catalysis where the molecularly imprinted polymers are used as enzyme mimics (Chapter 24). (D) Sensors and biosensor-like devices where the molecularly imprinted polymer is the recognition element (Chapters 26 and 27). 

Molecular imprinting offers the intriguing possibility of offering the synthetic chemist the opportunity to perform selective reactions in highly defined stereochemical environments. As MIPs can be designed to perform almost any chemical task and are inherently stable, their use in industrial processes would be especially interesting. From a more fundamental perspective, there is also the drive to create artificial materials that can truly function as enzyme mimics. This section will focus on a few of the more prominent examples of the use of MIPs in synthesis and catalysis." The first reports of MIPs employed in chemical synthesis came from Damen and Neckers and were followed by... 

In recent years, the studies in the field of homogeneous catalytic oxidation of hydrocarbons with molecular oxygen were developed in two directions, namely, the free-radical chain oxidation catalyzed by transition metal complexes and the catalysis by metal complexes that mimic enzymes. Low yields of oxidation products in relation to the consumed hydrocarbon (RH) caused by the fast catalyst deactivation are the main obstacle to the use of the majority of biomimetic systems on the industrial scale. 

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