Phosphorus–nitrogen compounds: Novel fully substituted spiro-cyclophosphazenic lariat (PNP-pivot) ether derivatives. Structures of 4,4,6,6-tetrapyrrolidino-2,2-[3-oxa-1,5-pentane dioxy bis(2-phenylamino)]cyclo-2λ5,4λ5,6λ5-triphosphazene and 4,4,6,6-tetrap

The condensation reaction of partly substituted spiro-cyclophosphazenic lariat (PNP-pivot) ethers, N3P3[(o-NHPhO)2R]Cl4 (5–8), where R=–CH2CH2–, –CH2CH2CH2–, –CH2CH2OCH2CH2–, and –CH2PhCH2–, with pyrrolidine have been afforded fully substituted pyrrolidino phosphazene derivatives (9–12) (Scheme). There are the first examples of the spiro-cyclophosphazenic lariat (PNP-pivot) ether ligands with N2Ox-(x=2, 3) donor type containing 11–14 membered macrocycles. The solid state structures of (11 and 12) have been determined by X-ray diffraction techniques. Evidently, in the macrocyclic ring of the compound (11), there are two three-centered (bifurcate) N–H⋯O/N–H⋯N hydrogen bonds, while compound (12) has two intramolecular N–H⋯O bonds. The relative radii of macrocyclic hole sizes of the compounds (11 and 12) are 1.25 and 1.10 Å, respectively. The structures of the new compounds (9–12) have also been examined by FTIR, 1H-, 13C-, 31P-NMR, MS and elemental analysis. Compound (11) crystallizes in the Pcab space group with a=9.8474(13), b=18.466(2), c=38.9375(19) Å, V=7080.7(14) Å3, Z=8 and Dx=1.317 g cm−3, while compound (12) crystallizes in P-1 space group with a=9.3724(5), b=11.2613(9), c=20.401(2) Å, α=93.177(8), β=102.115(7), γ=105.360(5)°, V=2016.0(3) Å3, Z=2 and Dx=1.268 g cm−3. The structures of (11 and 12) consist of nearly planar and non-planar trimeric phosphazene rings with spiro-cyclic bulky N2O3 and N2O2 macrocycles, respectively.