(Z)-3-Diethyl­amino-6-({2-[(E)-4-(diethyl­amino)-2-hy­droxy­benzyl­idene­amino]-4,5-dimethyl­phen­yl}amino­methyl­idene)cyclo­hexa-2,4-dienone–5,5′-bis­(diethyl­amino)-2,2′-[4,5-dimethyl-o-phenyl­enebis(nitrilo­methyl­idyne)]diphenol

The asymmetric unit of the title Schiff base compound, C30H38N4O2, comprises two crystallographically independent mol­ecules, A and B. The structure is non-merohedrally twinned with a refined BASF ratio of 0.219 (6):0.701 (6). Mol­ecule B shows both phenol–imine and keto–amine tautomeric forms in a single structure. The dihedral angles between the central ring and the two outer rings are 5.9 (3) and 48.4 (3)° in mol­ecule A, and 48.3 (3) and 6.9 (3)° in mol­ecule B. Strong intra­molecular O—H⋯N and N—H⋯O hydrogen bonds generate S(6) ring motifs. The crystal structure is further stabilized by inter­molecular C—H⋯O, C—H⋯π and π–π inter­actions [centroid–centroid distances = 3.870 (4)–3.871 (4) Å]

3,3′-Dimeth­oxy-2,2′-[(4,5-dimethyl-o-phenyl­ene)bis­(nitrilo­methanylyl­idene)]diphenol

The asymmetric unit of the title compound, C24H24N2O4, comprises two crystallographically independent mol­ecules A and B. The dihedral angles between the central dimethyl-substituted benzene ring and the two outer benzene rings are 49.5 (1) and 5.06 (11)° in mol­ecule A, and 42.55 (8) and 5.77 (9)° in mol­ecule B. In each mol­ecule, two strong intra­molecular O—H⋯N hydrogen bonds generate two S(6) ring motifs. The crystal structure is further stabilized by inter­molecular π–π [centroid–centroid distances of 3.591 (1)–3.876 (1) Å] inter­actions

5,5′-Bis(diethyl­amino)-2,2′-[2,2-di­methyl­propane-1,3-diylbis­(nitrilo­methylidyne)]diphenol

The asymmetric unit of the title compound, C27H40N4O2, comprises one mol­ecule of a potentially tetra­dentate Schiff base ligand. The dihedral angle between the two phenyl rings is 67.13 (10)°. Strong intra­molecular O—H⋯N hydrogen bonds generate S(6) ring motifs. One terminal methyl among the four diethyl­amino groups is disordered over two positions with the refined site occupancy ratio of 0.660 (7)/0.340 (7)

{1,1′-[Butane-1,4-diylbis(nitrilo­methyl­idyne)]di-2-naphtho­lato}copper(II) ethanol monosolvate

The asymmetric unit of the title compound, [Cu(C26H22N2O2)]·C2H5OH, comprises a Schiff base complex and an ethanol mol­ecule of crystallization. The CuII atom shows a distorted square-planar geometry. The dihedral angle between the two aromatic rings is 48.16 (13)°. The crystal structure is stabilized by inter­molecular O—H⋯O and C—H⋯O hydrogen bonds and inter­molecular π–π inter­actions with centroid–centroid distances in the range 3.485 (2)–3.845 (3) Å

{2,2′-[(2,2-Dimethyl­propane-1,3-diyl­dinitrilo)­bis­(phenyl­methyl­idyne)]­diphenolato}nickel(II)

The asymmetric unit of the title complex, [Ni(C31H28N2O2)], comprises two crystallographically independent mol­ecules. The geometry around the NiII atom in each mol­ecule is distorted square planar. The dihedral angles between the two phen­oxy rings in each mol­ecule are 17.8 (4) and 36.5 (4)°. The crystal packing is stabilized by weak π–π inter­actions [centroid–centroid distance = 3.758 (5) Å] and C—H⋯π inter­actions

2-[4-(4,5-Dihydro-1H-pyrrol-2-yl)phen­yl]-4,5-dihydro-1H-imidazole

The mol­ecule of the title compound, C12H14N4, lies about a crystallographic inversion centre. The five- and six-membered rings are twisted from each other, forming a dihedral angle of 18.06 (7)°. In the crystal structure, neighbouring mol­ecules are linked by inter­molecular N—H⋯N hydrogen bonds into one-dimensional infinite chains forming 18-membered rings with R 2 2(18) motifs. The crystal structure is further stabilized by weak inter­molecular π–π stacking [centroid–centroid distance = 3.8254 (6) Å] and C—H⋯π inter­actions

{4,4′-Dimethyl-2,2′-[(2,2-dimethyl­propane-1,3-di­yl)bis­(nitrilo­methanylyl­idene)]diphenolato}nickel(II) monohydrate

In the title compound, [Ni(C21H24N2O2)]·H2O, both the complex mol­ecule and the water mol­ecule lie on a twofold rotation axis. The NiII ion is coordinated in a distorted square-planar geometry by the tetra­dentate ligand. The dihedral angle between the two symmetry-related benzene rings is 47.12 (8)°. In the crystal, pairs of symmetry-related O—H⋯O hydrogen bonds form R 2 2(6) ring motifs. In addition, there are weak inter­molecular C—H⋯O hydrogen bonds, and π–π stacking inter­actions with a centroid–centroid distance of 3.4760 (8) Å

{4,4′-Dibromo-2,2′-[2,2-dimethyl­propane-1,3-diylbis(nitrilo­methyl­idyne)]diphenolato-κ4 O,N,N′,O′}copper(II)

In the title compound, [Cu(C19H18Br2N2O2)], the CuII ion is in a tetra­hedrally distorted planar geometry, involving two N and two O atoms from the tetra­dentate Schiff base ligand. Inter­molecular C—H⋯O hydrogen bonds form an eight-membered R 2 2(8) motif. The dihedral angle betwen two benzene rings is 36.34 (9)°. There are inter­molecular Cu⋯Br [3.4566 (5) Å] and Cu⋯·N [3.569 (3) Å] contacts, which are significantly shorter than the sum of van der Waals radii of the relevant atoms. These inter­actions, along with the inter­molecular C—H⋯π and π–π [centroid–centroid distances of 3.709 (1) and 3.968 (2) Å] inter­actions, link neighbouring mol­ecules into a one-dimensional infinite chain along the c axis

5-[(E)-(5-Bromo-2-hy­droxy­benzyl­idene)amino]-1,3,4-thia­diazole-2(3H)-thione

In the title mol­ecule, C9H6BrN3OS2, the dihedral angle between the benzene ring and the five-membered ring is 5.5 (3)°. An intra­molecular O—H⋯N hydrogen bond forms an S(6) ring motif. In the crystal, N—H⋯S hydrogen bonds link mol­ecules into centrosymmetric dimers creating R 2 2(8) ring motifs. In addition, there are inter­molecular S⋯S [3.430 (2) Å] contacts. The crystal used was a non-merohedral twin with a ratio of 0.113 (3):0.887 (3) for the components

(E)-N′-(4-Chloro­benzyl­idene)-p-toluene­sulfonohydrazide 0.15-hydrate

The asymmetric unit of the title compound, C14H13ClN2O2S·0.15H2O, a novel sulfonamide derivative, comprises two crystallographically independent mol­ecules (A and B) and a water mol­ecule of crystallization, which is partially occupied. One of the mol­ecules (B) is disordered over two positions (B and C) with refined site occupancies of 0.605 (10) and 0.395 (10). The dihedral angles between the two benzene rings in mol­ecules A, B and C are 67.8 (3), 74.6 (5) and 84.96 (11)°, respectively. In the crystal structure, inter­molecular N—H⋯O and C—H⋯O hydrogen bonds link the components of the asymmetric unit. The crystal structure is further stabilized by inter­molecular π–π inter­actions [centroid–centroid distances = 3.4518 (10)–3.5859 (10) Å]