trans-2,4,4,6,8,8-Hexamorpholino-2,6-bis(n-propylamino)cyclo-2lambda5,4lambda5,6lambda5,8lambda5-tetraphosphazatetraene.

The title compound, C(30)H(64)N(12)O(6)P(4), consists of a centrosymmetric chair-shaped cyclic tetrameric phosphazene ring with six bulky morpholino and two n-propylamino side groups. The two n-propylamino side groups are in trans positions. The bulky substituents mainly determine the eight-membered-ring conformation. The endocyclic N-P-N angles around the P atoms having different substituents are not the same as the P-N-P angles of the macrocyclic ring.

4-([(1E)-(2-Hydroxyphenyl)methylidene]amino)-1,5-dimethyl-2-phenyl-2,3-dihydro-1H-pyrazol-3-one.

In the title compound, C18H17N3O2, a strong intramolecular O-H...N hydrogen bond [N...O 2.607 (3), O-H 0.97 (3) and H...N 1.71 (3) A, and O-H...N 153 (2) degrees ] was observed, which leads to a unique phenol-imine tautomerism in the solid state. The C=N imine bond distance and the C-N-C bond angle [1.287 (2) A and 121.7 (1) degrees, respectively] indicate the existence of this phenol-imine tautomer. In solution, the phenol-imine tautomer of the title free Schiff base ligand is dominant in both polar and non-polar solvents, as supported by 1H NMR and UV-visible spectroscopic data.