Redetermination of Crystal Structure of N,N'-bis (2-Hydroxybenzylidene)-2,2-Dimethyl-1,3-Propanediamine

The structure of N,N'-bis(2-hydroxybenzylidene)-2,2-dimethyl-1,3-propanediamine, C19H22N2O2, has been studied at low temperature (120K) by means of single-crystal X-ray diffraction. Solving the structure shows an orthorhombic unit cell, with P212121 space group, Z = 4, a = 6.1046 (4) Å, b = 15.8349 (11)Å, c = 17.2898 (12) Å and V = 1671.3 (2) Å3. There are two relatively strong hydrogen bonds (average O—H···N, 2.59 Å), involving the hydroxyl group and the nearest N atom of the imine groups is an indicative of intra-molecular hydrogen bonding within each salicylideneimine moiety.  C-H…π interactions connect the neighboring molecules together, stabilizing the crystal network. No significant p-p interactions are present in the crystal structure.