Phosphorus Derivatives of Large Organic Molecules with Cavities

29 Phosphorus Derivatives of Large Organic Molecules with Cavities 

A potential for large ring and cavity formation extends to many P-containing organic molecules, in addition to the inorganic phosphates discussed above. These compounds include phosphate derivatives of fashionable structures such as crown ethers, calixarenes, carceplexes, catenanes, rotaxanes, self-assembly molecules and so on, and varieties which are discussed in Chapter 10, such as cyclo-dextrins, phosphosaccharides, phosphoproteins and nucleic acids. Phosphorus analogues of cyclo-polypyridyls and porphyrins are discussed in Chapters 7 and 8. 

Phosphonito (5.390a), phosphinito (5.390b) and phosphonate (5.390c) calixarene-[4] derivatives and other P-containing cavitands have been prepared [190-195]. Some of these compounds are useful as catalysts and others are possible metal extractants [196]. 

Phosphorus-containing calixarenes (5,390c) andresorcinarenes (5.390d) have recently been reviewed [197]. Phosphonated calixarenes have recently been utilised to obtain Ag nanoparticles [198]. Phosphorylated calix[8] arenes have been prepared [170]. 

The synthesis of phosphorus analogues of cryptate ligands such as (5.392) seems not unlikely in the near future. Like the multidentate nitrogen ligands, they may be expected to stabilise certain ions by encapsulation. Diphosphate crown ethers such as (5.393) have already been reported. These compounds are fairly easy to make (5.394). 

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