title: 2,2'-{1,1'-[Pentane-1,5-diyl-bis(oxy-nitrilo)]-diethyl-idyne}diphenol.
abstract: In the title compound, C(21)H(26)N(2)O(4), there is half a mol-ecule in the asymmetric unit with a crystallographic twofold rotation axis passing through the central C atom of the -CH=N-O-(CH(2))(5)-O-N=CH- bridge. The dihedral angle formed by the two benzene rings is 80.85 (2)°. Strong intra-molecular O-H⋯N and C-H⋯O hydrogen bonds help to establish the molecular conformation. There are also weak inter-molecular π-π stacking inter-actions between neighbouring benzene rings [centroid-centroid separation = 3.502 (3) Å].
authors.affiliation: School of Chemical and Biological Engineering, Lanzhou Jiaotong University, Lanzhou 730070, People's Republic of China.
authors.forename: Wen-Kui
authors.initials: WK
authors.lastname: Dong
authors.forename: Zhong-Wu
authors.initials: ZW
authors.lastname: Lv
authors.forename: Xue-Ni
authors.initials: XN
authors.lastname: He
authors.forename: Yong-Hong
authors.initials: YH
authors.lastname: Guan
authors.forename: Jun-Feng
authors.initials: JF
authors.lastname: Tong