New Lariat Ether-Type Macrocycles with Cyclophosphazene Subunits

Abstract

New side-armed ligands of lariat ether type 6-13 have been synthesized by the respective phenolysis and naphtholysis reactions of the parent isomeric ansa (2,4) and spiro (3,5) macrocyclosubstituted cyclophosphazenes of general formula N3P3CldO(CH&H~0),] (where n = 4,5), separated by column chromatograhy, and characterized by mass spectrometry and IH and 31P NMR spectroscopies. The synthesized side-armed ligands 6-13, as well as their respective functional chlorine-containing precursors 2-5, represent crown ethers with cyclophosphazene subunits and may thus be considered as diphosphaza[l6lcrown-6 or PNP16C6 (2,6,10), diphosphaza[19lcrown-7 or PNP19C7 (4,8,12), phospha[l4]crown-5 or P14C5 (3,7, 111, and phospha[l7lcrown-6 or P17C6 (5,9, 13). The one-pot method of synthesis developed for (aryloxy)-crowns 6-13, with the phenolysis (or naphtholysis) performed in situ immediately after completing the formation of the respective chlorine-containing macrocycles 2-5, made it possible to obtain high yields of the corresponding 16-and 19-membered ansa-PNP-cyclosubstituted side-armed diphosphaza-crowns PNP16C6 and PNP19C7 (6,8,10,12) and to isolate the stable 14-and 17-membered spiro-P derivatives P14C5 and P17C6 (7,9, 11,13), inaccessible by other synthetic routes. The diphosphaza-crowns thus obtained with B-naphthoxy substituents (10,121 offer promising prospects as new ligands of the P-pivot lariat ether type, capable of complexing both alkali and transition metal cations and of potential catalytic activity in phase and electron-transfer processes.

Competitive formation of spiro and ansa derivatives in the reactions of tetrafluorobutane-1,4-diol with hexachlorocyclotriphosphazene: A comparison with butane-1,4-diol

“…Reaction of (1) with (2) in THF was also effected in the presence of pyridine at room temperature; in this case, although there was evidence of the formation of spiro (3) and ansa (4) compounds as major products of the reaction, many more minor derivatives were formed, including decomposition products. All the ansa and spiro derivatives reported in this work were found to be unaffected by exposure to air and/or moisture, in contrast to previous reports [14,19] that spiro isomers are highly unstable to air and/or moisture, though their ansa isomers are stable. The reaction of the hexachloride (1) with the sodium derivative of the fluorinated diol, (2) was also carried out at -78º, in order to compare our results most closely with those reported by Elias and co-workers [14].…”

“…The magnitudes of 2 J(FF) are in line with previous results on geminal coupling [21]. It should be noted that the line-widths of the 19 F NMR signals of the spiro moiety are narrower than those for the ansa moiety, which might reflect the fact that the spiro moiety is more flexible than the ansa moiety.…”

“…silica gel was used in a column of 3 cm in diameter and 60 cm in length). 1 H, 19 F and 31 P NMR spectra were recorded in CDCl 3 solutions on a Bruker DRX 500 MHz spectrometer using TMS as an internal reference for 1 H, CFCl 3 as an internal reference for 19 F and 85% H 3 PO 4 as an external reference for 31 P. In order to assign the signals of some compounds both proton-coupled and proton-decoupled 19 F and 31 P NMR spectra were recorded.…”

“…The proton-decoupled 19 F NMR spectrum of the spiro form of the 2,2,3,3-tetrafluoro-1,4-butanedioxy moieties exists as a single line with essentially the same chemical shift (Table 1) for compounds (3), (5), (6) and (8), whereas the ansa form gives rise to an AB spin system with 2 J(FF) ca. 283 Hz for compounds (4) and (6) and two AB spin systems with 2 J(FF) ca.…”

Water‐Induced Rearrangement of a Platinacyclic Carbene Produces a Platinacyclic Carbaphosphazene with an Intraannular PtC Bond in a PtNPNPC Ring

“…A large body of synthetic phosphazine chemistry has furnished a wide array of organocyclophosphazenes with exocyclic PÀE bonds (E = O, S, N, and C). [2] More recently, the cyclophosphazenes have served as ligands for transition metals, [3,4] and their complexes have found application in catalysis, [5] dendrimers, [6] and cancer therapeutics. [7] Cyclophosphazenes containing metal centers that are covalently bonded in the ring (e.g., I-IV; Scheme 1) are also well established, [8] but have a shorter history: the first example was reported by Roesky et al in 1986 (I, M = WCl 3 , R = Ph).…”