Historical Background of Macrocyclic Compounds

Abstract

The design and synthesis of new macrocyclic compounds remains of interest because macrocyclic compounds are of major importance in the field of supramolecular chemistry. However, it is rare that chemists discover new classes of macrocyclic compounds, which may show great potential for application and open new avenues for chemists to explore these novel supramolecular systems and materials. Charles Pedersen's paper, published in the Journal of the American Chemical Society, on the discovery of crown ethers, was the starting point of supramolecular chemistry using artificial macrocyclic compounds. Cyclodextrins, crown ethers, and calix[n]arenes have dominated supramolecular chemistry for the past 50 years. The breakthrough paper published by Kim in 2000 contributed to the development of cucurbit[n]uril chemistry. Subsequently, cucurbit[n]urils were also classed as of major importance in supramolecular chemistry. Building on this historical background, one of the new classes of macrocyclic compounds, pillar[n]arenes, appeared in the literature in 2008, and is becoming dominant in the field of macrocyclic chemistry along with the other four key components. In this chapter, first we discuss the interesting points of macrocyclic compounds. Second, we present the key features of the four key classes of compounds in supramolecular chemistry. Other well-known macrocyclic compounds and new compounds showing great potential in macrocyclic chemistry are also mentioned. Finally, we discuss what factors are important in making macrocyclic compounds dominant in the field of supramolecular chemistry.