Ion and Molecular Recognition by Lower Rim 1,3-Di-conjugates of Calix[4]arene as Receptors

Abstract

Introduction 4658 2. Functionalization at the 1,3-Positions of Calix[4]arene 4659 3. Cation Receptors 4660 3.1. Zn 2þ Recognition 4660 3.1.1. Receptors Possessing Imino-phenolic Core 4660 3.1.2. Imino-phenolic Core Linked through Triazole Moiety 4661 3.1.3. Receptors Possessing Cores Other than the Imino-phenolic Ones 4661 3.2. Cu 2þ Recognition 4663 3.2.1. Cyclic Conjugates 4663 3.2.2. Noncyclic Conjugates 4664 3.3. Monomer/Excimer Emissions in the Presence of Fe 3þ 4666 3.4. Hg 2þ Recognition 4666 3.4.1. Cyclic Conjugates 4666 3.4.2. Noncyclic Conjugates 4667 3.5. Pb 2þ Recognition 4670 3.6. Ag þ Recognition 4671 3.7. Al 3þ Recognition 4673 3.8. Recognition of Alkali Metal Ions 4673 3.9. Recognition of Alkaline Earth Metal Ions 4676 3.10. Lanthanide Ion Recognition 4678 4. Anion Receptors 4680 4.1. Inorganic Anions 4680 4.1.1. Fluoride Recognition 4680 4.1.2. Chloride Recognition 4681 4.1.3. Iodide Recognition 4682 4.1.4. Chromate Recognition 4682 4.1.5. HSO 4 À and HSO 3 À Recognition 4683 4.1.6. Phosphate Recognition 4684 4.1.6.1. Recognition of Phosphate by Uncomplexed Calix[4]arene Conjugates 4684 4.1.6.2. Recognition of Phosphate by a Metal Complex of Calix[4]arene Conjugate 4686 4.2. Organic Anions 4687 4.2.1. Acetate Recognition 4687 4.2.2. Recognition by Dicarboxylates 4688 4.3. Chiral Recognition by Calix[4]arene Conjugates 4689 5. Amino Acids and Other Molecular Recognition 4693 5.1. Recognition of Amino Acids by Uncomplexed Calix[4]arene Conjugates 4693 5.2. Recognition of Amino Acid by Metal Complexes of the Calix[4]arene Conjugates 4694 5.3. Recognition of Other Molecular Species 4695 6. Conclusions and Future Perspectives 4697 Author Information 4698 Biographies 4698 Acknowledgment 4698 List of Abbreviations 4698 References 4699

Bis(spirolactam) 1,3-double-armed calix[4]arene compounds and their application as extractants for the determination of heavy metal ions

“…Calix [4]arenes are an important class of macrocyclic compounds which have been used extensively in supramolecular chemistry for molecular recognition [3][4][5][6]. They were first prepared by Baeyer in 1872, as by-products in the synthesis of baeklite [7].…”

“…Since Gutsche first published the synthesis of calix [4]arene-based macrocycles [11], the investigation of the complexation properties of these compounds has been of intense interest for a wide variety of ionic species and small organic guest molecules, through the formation of host-guest or supramolecular complexes. This area is subject to regular in-depth reviews [3][4][5][6].…”

“…Much of the current research into calixarenes focuses on the smallest and most rigid of the family, namely the calix [4]arenes, since the larger cavity-containing analogues are more flexible and therefore not always suited to strong binding with guest species, and are also generally less selective. Many calix [4]arene compounds have been synthesised over the last 40 years, with a variety of ligating groups to fine-tune binding to an array of ionic and neutral guests in solution and in the solid state [3][4][5][6]. Some of the functionalities attached to the calixarene scaffold are large and while they can facilitate binding can crowd the cavity and decrease the binding strength.…”

“…Some of the functionalities attached to the calixarene scaffold are large and while they can facilitate binding can crowd the cavity and decrease the binding strength. In order to overcome this potential issue chemists have devised calix [4]arenes where only two of the phenolic OH groups possess ligating groups.…”

“…These are referred to as 1,3-distal derivatised calix [4]arenes. In our previous work, we have synthesised such 1,3-distal derivatives which have been used in nanostructures capable of selectively sensing Li + and Fe 3+ in aqueous solution [12].…”