Molecular structures cyclophosphazenes

Nuclear magnetic resonance spectroscopy has emerged as the most powerful tool for elucidating the molecular structures of cyclophos-phazene derivatives in solution. Proton NMR spectroscopy has been widely used because of its easy accessibility. The recent development of sophisticated instrumental facilities and the application of broadband proton decoupling have greatly improved the quality and usefulness of the 31P spectra (252) of cyclophosphazenes, and it is likely that this technique will become increasingly popular in the future. Fluorine NMR studies are useful for deducing the structures of fluorocyclophosphazenes, and the potential of this technique has been demonstrated in recent years (209, 210, 213, 307, 308, 343). 

We had the privilege to solve the X-ray structure of the first ANSA derivative and we shall report in the next section the crystal and molecular structure of a cyclophosphazene linked to a difunctional tumor finder-like in a new configuration, i.e. the ANSA one 55 ... 

Cyclophosphazenes have been studied by a number of spectroscopic methods as well as by X-ray crystal structures. These studies have helped not only in understanding the molecular structures of cyclophosphazenes but have also shed a great deal of light on the nature of bonding that exists in these compounds [1, 5, 7, 9,10]. 

The reaction of a ID organostannoxane coordination polymer (121) with bis(biphenyloxy)bis(4-pyridylo3y) cyclophosphazene (122) afforded molecular (123) and polymeric cyclophosphazene-organostannoxane hybrid motifs (124) (Scheme 16). These compounds have been structurally characterized by NMR and X-ray crystallography. Previous work on the metalation studies of cyclophosphazene ligands has been summarised in two comprehensive review articles. ... 

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