Cyclophosphazene inclusion compounds

Muller and co-workers (02JPC(B)7781) investigated the molecular behavior of perdeuterated 1,3,5-trioxane in a cyclophosphazene inclusion compound by dynamic 2D NMR spectroscopy. The experimental data revealed a relatively complex motional behavior (rotational motion around the C3 axis of the molecule and around the channel long axis) in the phosphazene host channels the ring inversion process was almost uneffected by the host lattice and activation barriers, as reported from solution NMR studies (90JPC8845), were derived. 

Muller and coworkers have recently reported the molecular behavior of 1,3,5-trioxane in a cyclophosphazene inclusion compound using H-2 NMR [68]. The experimental data were obtained by variable-temperature line shape analysis, spin-spin and spin-lattice relaxation time measurements and by 2D exchange between 30 and 370 K. At room temperature, highly mobile trioxane guests were observed. They undergo various overall and conformational motions which give rise to substantial orientational disorder within the hexagonal cyclophosphazene channels. 

Cyclophosphazenes (183) containing a crown ether and a-amino acid units have been prepared starting from diphosphaza[16]crown-6 (182) (Scheme 51). Due to their topology, these compounds could give stable inclusion complexes, especially with alkali metal and alkaline-earth metal cations, in organic solvents. ... 

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