Hexakis-2-(β-carboxyethenylphenoxy)cyclotriphosphazene: Synthesis, Properties, Modeling Structure

Abstract

Condensation of hexakis-2-(formylphenoxy)cyclotriphosphazene with malonic acid yielded hexakis-2-(β-carboxyethenylphenoxy)cyclotriphosphazene (2-CEPP), whose structure was confirmed by 31P, 1H, 13C NMR spectroscopy and MALDI-TOF mass spectrometry. A quantum-chemical calculation for the 2-CEPP molecule using the ab initio methods in the 6-311G** basis set and the DFT-PBE0/6-311g** method was performed with geometry optimization of all parameters by the standard gradient method. The acid strength of 2-CEPP was theoretically estimated. Using the small-angle X-ray scattering method, it was found that 2-CEPP is an amorphous substance, which, when heated, can transform into a crystalline state. However, when heated at 370 °C, 2-CEPP undergoes decarboxylation and polymerization to form an insoluble heat-resistant product. The occurrence of decarboxylation and polymerization reactions in the formed styrene fragments was confirmed by thermal (differential-scanning calorimetry) and spectral (solid-state 13C NMR spectroscopy) analysis.

Progress in the Field of Cyclophosphazenes: Preparation, Properties, and Applications

“…Hence, Yudaev et al [ 18 ] synthesized a novel carboxyl-containing phosphazene, specifically hexakis-2-(β-carboxyethenylphenoxy)cyclotriphosphazene (2-CEPP), and explored its properties. This investigation is crucial for assessing the compound’s suitability as a modifier for epoxy resins.…”

“…Bişolu et al [18] described the synthesis of the 1D Cu 2+ coordination polymer (7) (Scheme 15) and the [L2(CuCl 2 )]n complex imidazole along with biphenyl-appended cyclotriphosphazene (6) (Scheme 15). Spectroscopic investigations (IR, 31 P, and 1 H NMR), MALDI-MS, and elemental analysis were used to identify the structure of 7.…”

“…H6L1 was used in the synthesis along with the structural elucidation of a polymeric as well as two 3D Cd 2+ CPs by Erkovan et al [31]. These are the coordinating polymeric compounds: GTU-1 (18) and GTU-2 (19). FTIR spectroscopy, powder X-ray diffraction, and SCXRD analyses were used to characterize Cd(II) coordination polymers.…”

“…Several synthetic approaches have been devised for the preparation of cyclotriphosphazene, involving the chemical modification of cyclotriphosphazenes through reactive functional groups [ 1 ]. These strategies yield prepolymers with versatile applications, including but not limited to coatings, adhesives, composites, anticancer medications [ 2 , 3 ], tumor growth inhibitors, flame retardants [ 4 , 5 , 6 ], biologically active molecules [ 7 , 8 , 9 ], antimicrobial reagents [ 10 ], organic light emitting diodes [ 10 , 11 , 12 ], catalysis [ 13 , 14 ], fluorescent dyes [ 15 , 16 , 17 ], polymerization [ 18 , 19 , 20 , 21 , 22 ], gas separation membranes [ 23 ], medicinal chemistry [ 24 ], lubricant additives [ 25 ], and inorganic chemistry [ 1 , 26 ].…”

“…The most abundant heterocyclic molecule, hexachlorocyclotriphosphazene (HCCP), has been employed as a precursor in the creation of cyclotriphosphazenes [ 27 ], and is a trimer with six active phosphorus and six active chlorine that is easily functionalized by nucleophilic substitution processes involving various nucleophiles, among which are amines, organometallic reagents, aryloxides, alkoxides, alcohols, and carboxyl groups, etc. [ 1 , 18 , 28 , 29 , 30 ].…”