Synthesis and spectral characterization of cyclotriphosphazene based 18-membered macrocycles

New 18-membered cyclotriphosphazene-containing macrocycles 7-10 were obtained by 1 + 1 condensation reaction of [dispiro-N3P3(C12H8O2)2((N(Me)NCH)2 N4C20H26)] (2) with N,N′-dimethyl-ethylenediamine-1,4-diyldimethylenebis(4-methyl-2-formylphenol) (3), N,N′-dimethyl-ethylenediamine-1,4-diyldimethylenebis(4,5-dimethyl-2-formylphenol) (4), N,N′-dimethyl-ethylenediamine-1,4-diyldimethylenebis(5-chloro-2-formylphenol) (5) and N,N′-dimethyl-ethylenediamine-1,4-diyldimethylenebis(5-bromo-2-formylphenol) (6), respectively.

A facile procedure for the assembly of macrocycles containing cyclophosphazene rings. The phenol oxygen and imino and amino nitrogen atoms present in the macrocyclic cavity can be utilized for coordination to metal ions.Figure optionsDownload as PowerPoint slideHighlights
► We have designed and synthesized new macrocycles by condensation reaction.
► The condensation reaction is very selective and yield only 1 + 1 condensed product.
► The macrocycles can accommodate any metal ions.
► The macrocyclic cavity can be easily fin-tuned.