Anion host design

One important reason for the mediocre performance of many artificial hosts may originate from the ambiguity of the binding modes. If we take host-guest binding of anions in water as an example, the blueprint of host design almost always relies on the creation of polar interactions which should attract the guest... 

The issues relevant in the construction of anion hosts cannot be grouped in a hierarchical order as there is an intimate interplay between all of them. Successful design mandates a balanced compromise in weighting the individual influences. Advice can and should be sought from pertinent calculations (molecular modelling/dynamics), from the successes and the very few examples of failure accumulated in the literature and collected in recent reviews [21-24], from inspiration provided by abundant biological examples and crystal structures, and not least from personal experience in the handling... 

Hay BP, Firman TK, Moyer BA (2005) Structural design criteria for anion hosts strategies for achieving anion shape recognition through the complementary placement of urea donor groups. J Am Chem Soc 127 1810-1819... 

The values for H3PO4 are 2.1,6.2 and 12.4. From your reading of this chapter, or otherwise, suggest possible hosts types that may be selective for the anions H2P04, HP04 and P04. What might be key considerations in the host design process ... 

Ballester provides an interesting account of anion - n interactions and their impact in host design. Over the past few years there has been mounting evidence that this type of interaction plays an important role in anion recognition. The chapter starts with a detailed overview of the theoretical aspects of anion - n interactions which is followed by a discussion of the existing... 

---