2-({[(2S)-1-Hydroxy-1,1,3-triphenylpropan-2-yl]imino}methyl)-4,6-bis(4-methylphenyl)phenol

The title compound was prepared and fully characterized. The salicylaldehyde alcohol is engaged in an intramolecular O—H⋯N hydrogen bond with the imine nitrogen.


Structure description
We have synthesized a number of chiral imine diols by Schiff-base condensation of the corresponding salicylaldehydes with (S)-2-amino-1,1,3-triphenylpropanol Liu et al., 2004). These compounds serve as ligands for titanium for the asymmetric intramolecular hydroamination of aminoallenes (Sha et al., 2019;Fok et al., 2020). The absolute structure parameter of 0.1 (7) has a large uncertainty but the absolute configuration was verified by synthesis and polarimetry.
Unlike the significant bond alternation seen in related structures (Sha et al., 2019), the bonds within the phenol ring (C23-C28) are all between 1.391 (4) and 1.406 (4) Å . The aromatic rings on the benzyl and phenyl substituents have typical aromatic bond distances ranging from 1.34-1.41 Å . The aromatic C24-O2 bond at 1.354 (4) Å is data reports substantially shorter than the aliphatic C1-O1 bond of 1.435 (4) Å , as seen in related structures.

Refinement
Crystal data, data collection and structure refinement details are summarized in Table 2.

Figure 1
The asymmetric unit of the title compound, showing the atom-numbering scheme. The displacement ellipsoids are shown at the 50% probability level. Hydrogen atoms apart from H1 and H2 have been omitted for clarity and intramolecular hydrogen bonds are shown as dashed lines. Figure generated using CrystalMaker (Palmer, 2020).

2-({[(2S)-1-Hydroxy-1,1,3-triphenylpropan-2-yl]imino}methyl)-4,6-bis(4-methylphenyl)phenol
Crystal data  Special details Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.