catena-Poly[[diaquabis(1,3-dihydro-3-oxoisobenzofuran-1-acetato)copper(II)]-μ-N,N′-(ethane-1,2-diyl)dinicotinamide]

In situ lactonization of 2-carboxycinnamic acid to form bis(1,3-dihydro-3-oxo-1-isobenzofuranacetate (dibf) resulted in the the crystallization of [Cu(dibf)(edn)(H2O)2] n coordination polymer chains [edn = N,N′-(ethane-1,2-diyl)dinicotinamide].

The title compound, {[Cu(C 10 H 7 O 4 ) 2 (C 14 H 14 N 4 O 2 )(H 2 O) 2 ] n , contains octahedrally coordinated Cu II ions ligated by two bis(1,3-dihydro-3-oxo-1isobenzofuranacetate (dibf) ligands and two trans water molecules, linked by N, N 0 -(ethane-1,2-diyl)dinicotinamide (edn) ligands into mono-periodic coordination polymer chains.The dibf ligands exhibit a pseudo-mirror positional disorder over two positions in a 89.2 (3)/10.8(3) ratio; the central amide groups of the edn ligands are disordered pseudo-rotationally in the same ratio.These monoperiodic chain motifs are held into supramolecular di-periodic supramolecular layers by means of N-H� � �O hydrogen bonding between edn amide groups and unligated dibf carboxylate O atoms.In turn, the supramolecular layers are held by crystal packing forces into the full crystal structure of the title compound.

Structure description
Our group (Przybyla et al., 2019) and other groups (Wang et al., 2013) have demonstrated the utility of N,N 0 -(ethane-1,2-diyl)dinicotinamide) (edn) for the construction of divalent metal coordination polymers.The title complex was obtained by hydrothermal reaction of copper nitrate, 2-carboxycinnamic acid, and edn under basic conditions.
The asymmetric unit of the title compound contains a divalent copper atom on a crystallographic inversion center, one bis(1,3-dihydro-3-oxo-1-isobenzofuranacetate (dibf) ligand generated from the in situ lactonization of 2-carboxycinnamic acid (Murray & LaDuca, 2014), one weakly bound water molecule, and half of an edn ligand whose central C-C � bond is sited over another crystallographic inversion center.Operation of the inversion center at the Cu II atom results in a Jahn-Teller-distorted {N 2 O 4 } coordination environment (Fig. 1) whose elongated axial positions are filled by the bound water molecules.Trans pyridyl N donor atoms from two edn ligands, and trans carboxylate O atoms from two dibf ligands occupy the four equatorial positions.Bond lengths and angles within the coordination sphere are listed in Table 1.The dibf ligands in the title complex serve as monodentate capping ligands.Neighboring copper atoms are linked by dipodal edn ligands to construct [Cu(dibf)(edn)(H 2 O) 2 ] n coordination polymer chains that are oriented along the [110] direction (Fig. 2).Both the edn as well as the dibf ligands in the title complex are disordered (Fig. 3).For the edn ligand, the central N,N 0 -(ethane-1,2-diyl)diamide unit is disordered by a pseudorotation around the center of the ethylene group.Both the major and minor moiety are located on the crystallographic inversion center and are both exactly inversion symmetric.
The dibf disorder involves a pseudo-mirror operation, with inverted handedness for the saturated carbon atom C15 of the isobenzofuranone.The disorder is correlated via a close contact between hydrogen atoms of the major moiety edn ligand and the minor moiety dibf ligand [H7B� � �H10B i = 1.72A ˚, C7� � �C10B i = 3.31 (2) A ˚; symmetry code: (i) À x, 1 À y, À 1 À z].The disorder ratio in both ligands refined to exactly identical values, 89.2 (3)/10.8(3), indicating that the disorder of the edn ligand causes the disorder of the dibf ligand.The minor moieties of the dibf ligand are incompatible with each other due to a close contact between the lactone oxygen atoms O5B [O5B� � �O5B ii = 2.91 (7) A ˚; symmetry code: The [Cu(dibf)(edn)(H 2 O) 2 ] n chains aggregate into supramolecular layers parallel to the ab crystal planes (Fig. 4) by hydrogen-bonding donation from edn amide N-H groups to unligated dibf carboxylate O atoms, and by hydrogen-bonding donation from bound water molecules to ebn amide C O carbonyl groups (Table 2).Crystal packing forces between adjacent supramolecular layers along the c-axis direction afford the full tri-periodic crystal structure of the title compound (Fig. 5).

Figure 1
Copper coordination environment in the title compound with full ligand set.Displacement ellipsoids are drawn at the 50% probability level.The minor disorder components are not shown.Color code: Co, dark blue; O, red; N, light blue; C, black; H, pink.Symmetry codes are as listed in Table 1.NaOH solution were placed into 10 ml of distilled water in a Teflon-lined acid digestion bomb.The bomb was sealed and heated in an oven at 393 K for 24 h, and then cooled slowly to 273 K. Green crystals of the title complex were obtained in 19% yield.

Refinement
Crystal data, data collection and structure refinement details are summarized in Table 3.All H atoms attached to C atoms were placed in calculated positions and refined with a riding model, with the H atoms attached to N or O found via difference map and then restrained (with the exception of the minor disorder N-H bond in the dibf ligand (see below).The dibf carboxylate ligands and the amide groups of the edn ligands were refined as disordered over two sets of positions in a 89.2 (3)/10.8(3) ratio.The dibf ligand exhibits a pseudomirror positional disorder; the edn amide group displays a pseudo-rotational relationship between its disordered components.These were treated with PART commands.Within the disordered components, SIMU commands were employed to restrain the U ij components of the atomic displacement parameters in order to avoid non-positive definite atomic displacement parameters.SADI and SAME commands were employed for the disordered components to restrain the bond lenghts and angles of major and minor moieties to be the same within an e.s.d. of 0.02 A ˚, to ensure chemically reasonable bond length and angle values.The H atoms belonging to the bound water molecules were restrained with a DFIX command at 0.84 (2) A ˚.The amide proton of the major component of the disordered edn ligand was found and had its N-H bond distance restrained with a DFIX command at 0.88 (2) A ˚.The amide proton of the minor component was placed geometrically.EADP commands were used to constrain the atomic displacement parameters for carboxylate major and minor disordered components of the dibf ligand to exactly the same values, again to avoid nonpositive definite atomic displacement parameters.IUCrData (2023). 8, x230764  Pumford and LaDuca � [Cu(C 10 H 7 O 4 ) 2 (C 14 H 14 N 4 O 2 )(H 2 O) 2 ] 3 of 3 Computer programs: COSMO (Bruker, 2009), SAINT (Bruker, 2014), SHELXS (Sheldrick, 2008), SHELXL2018/3 (Sheldrick, 2015), OLEX2 (Dolomanov et al., 2009), and CrystalMaker X (Palmer, 2020).

Special details
Geometry.All esds (except the esd in the dihedral angle between two l.s.planes) are estimated using the full covariance matrix.The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry.An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s.planes.

Figure 3
Figure 3 Copper coordination environment in the title compound with full ligand set showing major and minor disordered components.Color code: Co, dark blue; O, red; N, light blue; C, black.H atoms have been omitted.The minor disordered components have bonds drawn as dashed lines.

Figure 5
Figure 5Stacking of supramolecular layers in the title compound.

Table 3
Experimental details.