A spirocyclic system comprising both phosphazane and phosphazene rings.

Area of Science:

• Inorganic Chemistry
• Materials Science
• Coordination Chemistry

Background:

• Cyclotriphosphazenes are versatile inorganic compounds with tunable properties.
• Phosphazanes are nitrogen-containing phosphorus compounds with unique ring structures.
• The synthesis of novel hybrid phosphorus-nitrogen frameworks remains a key area of research.

Purpose of the Study:

• To synthesize and structurally characterize a novel compound integrating both phosphazene and phosphazane rings.
• To explore the reactivity of this new hybrid structure as a precursor for extended phosphorus-nitrogen materials.
• To investigate the isomeric forms and potential applications of the synthesized compounds.

Main Methods:

• Reaction of hexakis(cyclohexylamino)cyclotriphosphazene with phosphorus trichloride to form a spirocyclic phosphazene-phosphazane.
• Structural characterization of the resulting compound, identifying isomeric forms.
• Further reaction of the synthesized compound with a primary amine to extend the phosphorus-nitrogen moiety.
• Reaction with antimony trichloride to form a tricyclic antimony-containing phosphazene derivative.

Main Results:

• The first structurally characterized compound containing fused phosphazene and phosphazane rings, [NP(CyN)(2)PCl](3) (2), was synthesized.
• Compound 2 exhibits isomeric C(3h) and C(s) forms due to stereoactive lone pairs on peripheral phosphorus atoms.
• The reactive PCl groups in compound 2 enable its use as a precursor for extended, rigid phosphorus-nitrogen structures.
• Reaction with primary amines yields extended structures like [NP(CyN)(2)PN(H)(t)Bu](3) (3).
• Reaction with SbCl(3) produces a tricyclic compound N(3)P(3)(CyNH)(4)(CyNSbCl(2))(2) (4) with antimony centers.

Conclusions:

• A novel spirocyclic phosphazene-phosphazane hybrid molecule has been successfully synthesized and characterized.
• This new compound represents a valuable building block for constructing complex and rigid phosphorus-nitrogen architectures.
• The study demonstrates the potential for creating diverse phosphorus-nitrogen materials through controlled synthetic modifications.