The design and synthesis of artificial receptors for sensing and recognition of anions have received considerable attention in supramolecular chemistry because of the essential roles that anions play in a wide variety of biological, clinical and environmental sciences. The usual design strategies for anion sensing are through hydrogen-bonding interaction, intermolecular proton-transfer reaction, the Lewis acid/base interactions or an irreversible specific chemical reaction. Compared to the conventional anion receptors containing the NH or OH binding sites, recently, the anion receptors based on CH group have attracted much attention. Therefore, this review summarizes the main design principles and sensing abilities of the anion receptors based on receptors which having alkyl CH groups, phenyl CH groups, triazole-based CH groups, imidazolium-based CH groups, triazolium-based CH groups, CHCN group.

Contents
1 Introduction
2 Alkyl-based CH groups
3 Phenyl-based CH groups
4 Triazole-based CH groups
5 Imidazolium-based CH groups
6 Triazolium-based CH groups
7 CHCN-based CH groups
8 Conclusion