(Z)-N-[(Z)-3-(2,5-Di-methyl-phenyl-imino)-butan-2-yl-idene]-2,5-di-methyl-aniline.

The asymmetric unit of the title compound, C20H24N2, contains one half-mol-ecule, with the single C-C bond of the 1,4-di-aza-butadiene fragment situated on a centre of symmetry. The benzene rings are inclined to the 1,4-di-aza-butadiene mean plane by 59.5 (1)°.

2-Methyl-1,1-diphenyl-2-[(4S)-4-phenyl-4,5-di-hydro-1,3-oxazol-2-yl]propan-1-ol.

In the title compound, C25H25NO2, the phenyl ring on the 1,3-oxazole ring is disordered over two positions with occupancies of 0.600 (4) and 0.400 (4). The inter-planar angle between these two disordered rings is 77.8 (2)°. There is an intra-molecular O-H⋯N hydrogen bond of moderate strength. In the crystal, C-H⋯π inter-actions interconnect neighbouring molecules. The absolute structure has been derived from the known absolute structure of the reagents.

(4RS)-Methyl 4-cyano-4-cyclo-hexyl-4-phenyl-butano-ate.

In the crystal structure of the title compound, C(18)H(23)NO(2), there are only van der Waals inter-actions present. The cyclo-hexyl ring has a chair conformation. The longer axes of the displacement parameters of the non-H atoms forming the ethyl-methyl-carboxyl-ate skeleton are perpendicular to the plane through the non-H atoms of this skeleton.