Chiral HPLC Separation, Absolute Structural Elucidation, and Determination of Stereochemical Stability of trans‐Bis[2‐(2‐pyridinyl)aminophenolato] Cyclotriphosphazene

Abstract

Chiral high-performance liquid chromatography (HPLC) separation of trans-bis[2-(2-pyridyl)aminophenolato] dichlorocyclotriphosphazene was achieved and the absolute configuration of was assigned to be S,S by single-crystal X-ray structural analysis. The optically pure 1,2-diphenyl-1,2-ethanediolate derivatives (+)- and (-)- were synthesized by the reactions of and with (R,R)-hydrobenzoin, respectively, in refluxing toluene in the presence of an excess amount of triethylamine and a catalytic amount of 4-(dimethylamino)pyridine. The racemization of the enantiomers of and the epimerization of diastereomers of 2 were not observed in refluxing toluene neither under acidic nor basic conditions. The stereochemistry of was confirmed by the crystal structure of (+)- and bis[(4-methyl-2-pyridyl)oxy]cyclotriphosphazene derived from . Chirality 28:556-561, 2016. © 2016 Wiley Periodicals, Inc.

Synthesis and spectroscopic properties of (N/O) mono- and dispirocyclotriphosphazene derivatives with benzyl pendant arms: study of biological activity

“…The aromatic C-H bands were between 3040 cm −1 and 3100 cm −1 . Moreover, the asymmetric ν PCl 2 vibrations of the partly substituted tetra (3 and 4) and dichloro phosphazenes (13)(14)(15)(16) were determined in the range of 562-576 cm −1 . These peaks were not observed in the IR spectra of the tetrakis-substituted monospirophosphazene derivatives (5-12).…”

“…The IR, APIES-MS, and microanalytical data of the products (7)(8)(9)(10)(11)(12)(13)(14)(15)(16) are tabulated in Table 8.…”

“…It is difficult to separate these isomers from each other; hence, very few optical and geometrical isomers of dispiro derivatives have been separated in the literature [9][10][11][12][13]. Geometric isomers of dispirocyclotriphosphazenes can be separated by column chromatography, while optical isomers may be determined using 31 P { 1 H}, circular dichroism, X-ray data, and/or high-pressure liquid chromatography [14][15][16][17]. Among these methods, X-ray data are important to define the absolute configurations of optically active phosphazenes.…”

“…The δ -values of the PhC H 2 N protons of the monospirocyclotriphosphazenes (3-12) appeared to be in the range of 4.15-3.86 ppm, like the doublets, due to vicinal coupling with the 31 P nucleus. However, the corresponding protons of the dispirocyclotriphosphazenes(13)(14)(15)(16) had an ABX spin system due to vicinal and geminal couplings with the P atoms and geminal protons, indicating that the 2 geminal protons of the PhC H 2 N were diastereotopic.In addition, the 3 J P H data of the phosphazenes possessing 5-membered spiro rings (3, were slightly smaller than those of the 6-membered rings(4, 6, 8, 10, 12, 14, and 16).The average 3 J P H couplings were 8.1 and 8.3 Hz for the 5-and 6-membered spirophosphazenes. Furthermore, δ -shifts of the NC H 2 and OC H 2 protons of the spiro-precursors were assigned in the ranges of 3.26-2.89 ppm and 4.43-4.21 ppm.…”

The reactions of N$_{3}$P$_{3}$Cl$_{6}$ with monodentate and bidentate ligands: the syntheses and structural characterizations, in vitro antimicrobial activities, and DNA interactions of 4-fluorobenzyl(N/O)spirocyclotriphosphazenes

“…10,11 Most of the * Correspondence: okumus@science.ankara.edu.tr chiral cyclotriphosphazene derivatives were obtained by reactions of achiral cyclotriphosphazenes with achiral bidentate reagents. 12 Aminocyclotriphosphazenes have also attracted much consideration for their potential as antibacterial, antifungal, and anticancer agents. 13,14 Some of the phosphazene derivatives were found to be active on different tumor cells, e.g., HT-29, Hep2, Vero, and DLD1 cells.…”