Cyclophane synthetic strategy

Coordinated and uncoordinated cyclophanes receive considerable interest due to the influence of strain on aromaticity [69]. Benzannulation adds a mild synthetic strategy to the known synthetic methods for their production, especially for coordinated cyclophanes, which have been mostly synthesized by the harsher direct coordination of pre-assembled cyclophanes. 

General Synthetic Strategies for Strained Compounds of the Cyclophane Type... 

The chiral macrocydes and cyclophanes that have been included in this Chapter have loosely been dassified with respect to the synthetic strategy employed to provide the asymmetric, cydic product. One of the simplest and most economical methods for introdudng chirality involves the use of only achiral building blocks to... 

Regardless of the synthetic strategy employed for their formation, carbon-rich chiral macrocycles and cyclophanes can be realized with both diverse structure and function. Modern synthetic techniques, in combination with more readily available... 

While nature uses coenzyme-dependent enzymes to influence the inherent reactivity of the coenzyme, in principle, any chemical microenvironment could modulate the chemical properties of coenzymes to achieve novel functional properties. In some cases even simple changes in solvent, pH, and ionic strength can alter the coenzyme reactivity. Early attempts to present coenzymes with a more complex chemical environment focused on incorporating coenzymes into small molecule scaffolds or synthetic host molecules such as cyclophanes and cyclo-dextrins [1,2]. While some notable successes have been reported, these strategies have been less successful for constructing more complex coenzyme microenvironments and have suffered from difficulties in readily manipulating the structure of the coenzyme microenvironment. 

The present volume is intended to provide this knowledge, showing synthetic principles and creative strategies for the above-mentioned classes of macrocycles with stress on crowns, strained and cavityshaped cyclophanes, expanded porphyrins and macrolide antibiotics. 

Synthetic methods for the preparation of azacycloalkanes and -cyclophanes also include modification of a preformed macrocycle. This is commonly performed by means of conventional functionalization reactions which do not follow particular strategies and are adequately described in the cited literature. Conversely, a large strategic effort has been dedicated to the preparation of topologically constrained ligands and linked-ring systems. The... 

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