(2Z,2′Z)-Diethyl 3,3′-[butane-1,4-diylbis(azanediyl)]bis(but-2-enoate)

Abstract

The whole molecule of the title β-enaminoester, C16H28N2O4, is generated by a crystallographic inversion center, situated at the mid-point of the central C—C bond of the 1,4-diaminobutane segment. There are two intramolecular N—H...O hydrogen bonds that generate S(6) ring motifs. This leads to the Z conformation about the C=C bonds [1.3756 (17) Å]. The molecule is S-shaped with the planar central 1,4-diaminobutane segment [maximum deviation for non H-atoms = 0.0058 (13) Å] being inclined to the ethyl butylenonate fragment [C—C—O—C—C=C—C; maximum deviation = 0.0710 (12) Å] by 15.56 (10)°. In the crystal, molecules are linked via C—H...O interactions, leading to the formation of an undulating two-dimensional network lying parallel to the bc plane.