Diversity-based approaches

Diversity-Based Approaches to Selective Biomimetic Oxidation Catalysis Albrecht Berkessel... 

Keywords Asymmetric synthesis, Chiral catalysis, Diversity-based approaches, Supported chiral catalysts, Solid-phase chemistry... 

Below, various investigations involving the development of new metal-catalyzed enantioselective reactions that utilize the principles of diversity-based approaches are highlighted. Several key studies have also been disclosed recently that correspond to identification of non-metal-based catalysts notable advances in this area are highlighted as well. 

Diversity-Based Approaches to the Discovery of Catalysts for Enantioselective Synthesis... 

Scheme 5. Diversity-based approaches used in the late nineties in connection to the development of catalytic asymmetric allylic substitution reactions...

A more recent application of diversity-based approaches to chiral catalyst identification is reported by Ding in connection to cycloadditions of Danishefsky... 

The research described herein bears testimony to the fact that use of combinatorial protocols is becoming increasingly popular with researchers in the important field of chiral catalyst discovery. The majority of the above examples represent cases in which combinatorial approaches have led to the development of a new method in organic synthesis. There are numerous other disclosures involving optimization of established protocols that benefited from diversity-based approaches as well [23]. 

Tian J, Coates GW, Development of a diversity-based approach for the discovery of stereoselective polymerization catalysts Identification of a catalyst for the synthesis of syndiotactic polypropylene, Angew. Chem. Int. Ed. Eng., 39 3626-3629, 2000. 

A diversity-based approach was examined to identify a polymeric palladium-phosphine complex exhibiting high stereoselectivity in water [8]. Thus, a library of... 

Diversity-Based Approach for Drug vs Catalyst Discovery. 2... 

This article provides a brief overview of the recently developed diversity-based approaches in the screening and identification of effective metal-based chiral catalysts for enantioselective synthesis. This first wave of reports indicates... 

Scheme 1. The diversity-based approach can provide a wealth of reactivity and selectivity data in an efficient manner...

DIVERSITY-BASED APPROACHES TO SELECTIVE BIOMIMETIC OXIDATION CATALYSIS... 

Scheme 6a. Diversity-based approach to iron-based enantioselective catalysts - the ligand library used for catalyst discovery.

Berkessel et al. took a diversity-based approach to the discovery of functional models for GOase 42). Based on the known coordination pattern of the catalytically active copper ion (X-ray crystal structure of GOase from Dactylium dendroides, schematically in Scheme 12), the peptide/peptoid library 29 (Scheme 13) was designed. In this library, the Gly-D-Pro-turn positions the four amino acids X -X such that they can coordinate a copper ion. The four positions X X were occupied, in a combinatorial manner, by either histidine, tyrosine, the Cys22s-Tyr272-model mod-Cys (30), and in particular the TEMPO-derived amino acid TOAC (31) (Scheme 13). Thus, the TOAC-derived library comprised a total of 81 decapeptides, and it was synthesized... 

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