Phosphorus-nitrogen compounds: Part 15. Synthesis, anisochronism and the relationship between crystallographic and spectral data of monotopic spiro-crypta phosphazenes

Abstract

The reactions of hexachlorocyclotriphosphazatriene, N 3 P 3 Cl 6 , with N 2 O 2 -donor type coronands,, respectively. The reaction of 4 with excess pyrrolidine leads to the formation of geminal. The 31 P-NMR spectra of 5 and 6 indicate that these compounds have anisochronism. The structures of 5, 6 and 7 were investigated by X-ray crystallography. For 7, the sums of the bond angles around the N atoms were 348⋅6(2)° and 349⋅7(2)° indicating that the N atoms have pyramidal configurations and are stereogenic. The relationship between the chemical shift values δP (spiro) and the Δ(P-N) (electron density transfer parameters) of 4, 5, 6, 7 and the analogous compounds as well as the relationship between the Δ(δP) values and the above mentioned Δ(P-N) are presented respectively. In addition, the relationship between the endocyclic NPN bond angles of these compounds and the 31 P-NMR chemical shifts of the spiro-phosphorus atoms were investigated. The spectroscopic and structural investigations of the compounds were made by elemental analyses, MS, FTIR, one-dimensional 1 H-, 13 C-, 31 P-NMR, DEPT and two-dimensional COSY, HETCOR, HMBC, homo-and heteronuclear correlation techniques.

Syntheses of Chiral Phosphazenes with Stereogenic Centers: NMR Behavior in the Presence of a Chiral Solvating Agent

“…In the literature, the condensation reactions of N 3 P 3 Cl 6 with secondary amines such as pyrrolidine and diethyl amine give essentially nongeminal phosphazenes with trans products predominating . In contrast to these observations, in our studies, only geminal products are isolated from the reactions of bulky‐crypta and pendant‐monoferrocenyl spirocyclotriphosphazenes with pyrrolidine, morpholine, and 1‐aza‐12‐crown‐4 , independent from the bulkiness of these amines. In this study, geminal products ( 1b – 5b ) are also isolated from the condensation reactions of tetrachloro pendant‐ferrocenyl spirocyclotriphosphazenes with morpholine, a secondary amine, indicating that the reaction mechanism is S N 1 (P) in the second stage of these reactions.…”

“…Aziridine, the smallest cyclic secondary amine, reacts to afford both the geminal and the nongeminal isomers in nearly equal amounts . Besides, contrary to the reactions of trimer with secondary amines, some tetrachloro bulky‐crypta and bulky‐monoferrocenyl spirocyclotriphosphazenes produce only the geminal products with pyrrolidine, morpholine, and 1‐aza‐12‐crown‐4.…”

Phosphorus-nitrogen compounds (Part 51): the relationship betweenspectroscopic and crystallographic data of mono- and di-spirocyclophosphazenederivatives with 4-fluoro/nitrophenylmethyl pendant arm/arms

“…Besides, there is a decrease in δ Pspiro shifts with increasing number of members in the spiro-ring. For example, the α ′ bond angles of partly substituted Ia with 5-membered spiro-ring (δ Pspiro = 19.22 ppm, cycle A) and Ic with 6-membered spiro-ring (δ Pspiro = 14.34 ppm, cycle B) are respectively; 95.46 (15) and 94.97 (17), and 103.9 (2). This indicates that the electron-releasing power of 5-membered spiro-ring to the phosphazene ring is more than that of the 6-membered spiro-ring.…”

“…In recent years, cyclotri and cyclotetraphosphazenes have started to attract much attention due to their potential stereogenic properties, and biological activities such as antibacterial, antifungal and anti-cancer activities [8][9][10][11][12]. Our group has spent many years on designating and synthesizing novel partly substituted cyclotri and cyclotetraphosphazene derivatives with bidentate ligands {dibenzo-diaza-crown ethers [13][14][15][16][17], dibenzo N 2 O n (n =2-4) [18][19][20][21] and benzo NO [22][23][24][25][26][27][28] donor * Correspondence: sbilge@science.ankara.edu.tr type aminopodands, mono-and bis-ferrocenyldiamines [29][30][31][32][33][34][35][36][37], sodium (ferrocenylmethylamino)-1-alkoxide [38][39][40][41][42][43]}and multidentate N 2 O 2 -donor type dibenzo aminopodands [44][45][46]. Some interesting phosphazene derivatives such as monotopic and ditopic spiro-crypta phosphazenes, spirocyclic phosphaza (PNP-lariat) ethers, cyclophosphazenes possessing 6-membered spiro ring/rings, mono and bisferrocenylspirocyclophosphazenes, and spiro-ansa-spiro-, spiro-bino-spiro-and ansa-spiro-ansa-phosphazenes were synthesized.…”

Phosphorus-nitrogen compounds- (Part 50): correlations between structuralparameters for cylophosphazene derivatives containing ferrocenyl pendant arm(s)

“…Shaw described the first systematic study of the relationship between the bond angles around the phosphorus atoms and 31 P NMR spectral data in phosphazene derivatives [42]. The changes in structural parameters for different kinds of structurally analogous cyclotriphosphazenes (cyclotriphosphazenes possessing 6-membered spiro ring/rings [43], monospiro-, dispiro-, spiro-ansa-spiro-and spiro-bino-spiro-cyclotriphosphazenes [44][45][46], spiro-cyclotriphosphazenic lariat (PNP-pivot) ether derivatives [47,48], monotopic and ditopic spiro-crypta cyclotriphosphazenes [49][50][51]) were investigated previously. It was found that the systematic variations in the 31 P NMR chemical shifts depend fundamentally on some electronic (electron-releasing and electron-withdrawing capacities of substituent groups), steric (the steric hindrance between the exocyclic groups) and conformational factors, and on the changes in bond lengths and bond angles around the phosphorus atoms [especially endocyclic ( α) and exocyclic ( α ′ ) bond angles] in cyclotriphosphazene derivatives.…”