Crystal structure of 2,4-di-tert-butyl-6-(hydroxymethyl)phenol

The title compound, C15H24O2, is an example of a phenol-based pendant-arm precursor. In the molecule, the phenol hydroxy group participates in an intramolecular O—H...O hydrogen bond with the pendant alcohol group, forming anS(6) ring. This ring adopts a half-chair conformation. In the crystal, O—H...O hydrogen bonds connect molecules related by the 31screw axes, forming chains along thecaxis. The C—C—O angles for the hydroxy groups are different as a result of the type of hybridization for the C atoms that are involved in these angles. The C—C—O angle for the phenol hydroxy group is 119.21 (13)°, while the angle within the pendant alcohol is 111.99 (13)°. The bond length involving the phenolic oxygen is 1.3820 (19) Å, which contrasts with that of the alcoholic oxygen which is 1.447 (2) Å. The former is conjugated with the aromatic ring and so leads to the observed shorter bond length.

Crystal structure of tetrakis(μ3-2-{[1,1-bis(hydroxymethyl)-2-oxidoethyl]iminomethyl}phenolato)tetracopper(II) ethanol monosolvate 2.5-hydrate

The title compound, [Cu4(C11H13NO4)4]·CH3CH2OH·2.5H2O, is an electronically neutral tetranuclear copper(II) complex with a cubane-like Cu4O4core. The complete molecule has point group symmetry 2. The phenol hydroxy group and one of the three alcohol hydroxy groups of each 2-{[tris(hydroxymethyl)methyl]iminomethyl}phenol ligand are deprotonated, while the secondary amine and the other two hydroxy groups remain unchanged. The CuIIatoms in the Cu4O4core are connected by four μ3-O atoms from the deprotonated alcohol hydroxy groups. Each of the pentacoordinated CuIIions has an NO4distorted square-pyramidal environment through coordination to the tridentate Schiff base ligands. The Cu—N/O bond lengths span the range 1.902 (4)–1.955 (4) Å, similar to values reported for related structures. There are O—H...O hydrogen-bond interactions between the complex molecules and the ethanol and water solvent molecules, leading to the formation of a three-dimensional network. The ethanol solvent molecule is disordered about a twofold rotation axis. One of the two independent water molecules is also located on this twofold rotation axis and shows half-occupancy.

Tris[2-(2-pyridyliminomethyl)phenolato(0.67−)]europium(III) nitrate

The title compound, [Eu(C12H9.33N2O)3]NO3, was obtained by the reaction of Eu(NO3)·3H2O and the Schiff base ligand 2-(2-pyridyliminomethyl)phenol. The Eu atom is located on a threefold rotation axis and is nine-coordinated by three tridentate Schiff base ligands in a distorted tricapped trigonal-prismatic geometry. The O atom at the phenol hydroxy group is partially deprotonated and the H atoms are modelled with one-third occupancy according to the space groupR\overline{3}. Offset face-to-face π–π [centroid–centroid distance = 3.886 (3) Å] and edge-to-face C—H...π interactions are found between adjacent molecules. An intramolecular O—H...N hydrogen bond is also present.