5,5′-Bis(diethyl­amino)-2,2′-[butane-1,4-diyldioxy­bis(nitrilo­methyl­idyne)]­diphenol

The title complex, C(26)H(38)N(4)O(4), was synthesized by the reaction of 4-diethyl­amino-2-hydroxy­benzaldehyde with 1,4-bis­(amino­oxy)butane in ethanol. It crystallizes as discrete centrosymmetric molecules adopting an extended conformation where the two salicylaldoxime groups are separated from each other. Intra­molecular O—H⋯N hydrogen bonding is observed between the hydr­oxy groups and oxime N atoms. Inter­molecular π–π stacking inter­actions [3.979 (2) Å] between aromatic rings are apparent in the crystal structure. Each ethyl group is disordered over two positions; in one the site occupancy factors are 0.55 and 0.45, in the other 0.53 and 0.47.