Synthesis of Macrocycles and Click Chemistry

The synthesis of macrocycles has evolved in recent years by using concepts developed in different areas of chemistry. We can summarize three key topics as follows  

3) Dynamic combinatorial chemistry, as a method for the generation of new molecules by means of reversible reactions between simple building blocks under thermodynamic control. In a dynamic combinatorial library (DCL), all constituents are in equihbrium, and their distribution is determined by their 

Click Reactions in Organic Synthesis, First Edition. Edited by Srinivasan Chandrasekaran. 

The key issue, whatever of the previous concepts is used, is to utilize efficient, high-yielding, functional-group-tolerant, orthogonal [9] organic chemistry for the ring-closing step (the macrocyclization reaction). 

In this chapter, we highlight recent examples of the use of the mentioned click reactions as the macrocyclization reaction in several contexts. We exclude the following from the current review (i) cyclic structures in which part of the cyclic connection is formed by noncovalent bonds [26] (ii) the postmodification with CuAAC click chemistry of preformed macrocycles in order to introduce triazoles for functional applications [27, 28] and (iii) coordination polymers, or metal-organic frameworks, formed by clicked struts or ligands [29]. This chapter is structured in several subchapters according to the different classes of macrocycles obtained. 

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Scheme 22 Synthesis of macrocyclic PVLs via organocatalyzed ROP and click chemistry. ...

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