Ligands diversity

At the origin of this abundance of publications on iV-heterocyclic carbenes is the structural ligand diversity now available (Fig. 1.2). This developing area is noteworthy as most early developments were mainly focused on imidazolylidene and imidazo-lidinylidene NHC-types. 

Figure 3. Some major types of centers (X) and lines (X—X) of stereoisomerism. Different degrees of ligand diversity are possible for most of these types.

Cole BM, Shimizu KD, Krueger CA, Harrity JPA, Snapper ML, Hoveyda AH, Discovery of chiral catalysts through ligand diversity Ti-catalyzed enantiose-lective addition of TMSCN to meso epoxides, Angew. Chem., Int. Ed. Engl., 35 1668-1671, 1996. 

Keywords Chiral catalysts. Asymmetric synthesis. High-throughput screening, Ligand diversity, Solid phase chemistry... 

Discovery of chiral catalysts through ligand diversity Ti-catalyzed enantioselective addition of TMSCN to meso epoxides. Angew Chem Int Ed Engl 35 1668-1671. 1996. 

Snapper, Hoveyda and coworkers have used a ligand diversity approach for finding a catalyst for the addition of trimethylsilyl cyanide to epoxides. The basic ligand structure (12.130) was optimised using combinatorial techniques, which allowed for the parallel synthesis of over 20 ligands a day. Variation of the first amino... 

Abbott, DW Eirin-Lopez, JM Boraston, AB. Insight into ligand diversity and novel biological roles for family 32 carbohydrate-binding modules. Mol Biol EvoL, 2008, 25, 155-67. 

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