meso-4,4'-Dimeth-oxy-2,2'-{[(3aR,7aS)-2,3,3a,4,5,6,7,7a-octa-hydro-1H-benz-imidazole-1,3-di-yl]bis-(methyl-ene)}diphenol.

The title compound, C23H30N2O4, a di-Mannich base derived from 4-meth-oxy-phenol and cis-1,2-di-amine-cyclo-hexane, has a perhydro-benzimidazolidine nucleus, in which the cyclo-hexane ring adopts a chair conformation and the heterocyclic ring has a half-chair conformation with a C-N-C-C torsion angles of -48.14†(15) and -14.57†(16)°. The mean plane of the heterocycle makes dihedral angles of 86.29†(6) and 78.92†(6)° with the pendant benzene rings. The mol-ecular structure of the title compound shows the presence of two inter-actions between the N atoms of the imidazolidine ring and the hydroxyl groups through intra-molecular O-H⋯N hydrogen bonds with graph-set motif S(6). The unobserved lone pairs of the N atoms are presumed to be disposed in a syn conformation, being only the second example of an exception to the typical 'rabbit-ears' effect in 1,2-di-amines.