cis-(Acetato-κ2 O,O′)(5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-κ4 N,N′,N′′,N′′′)nickel(II) perchlorate monohydrate

The complete cation in the title hydrated molecular salt, [Ni(CH3CO2)(C16H36N4)]ClO4·H2O, is generated by the application of crystallographic twofold symmetry; the perchlorate anion and water molecule are each disordered around a twofold axis. The NiII atom exists within a cis-N4O2 donor set based on a strongly distorted octahedron and defined by the four N atoms of the macrocyclic ligand and two O atoms of a symmetrically coordinating acetate ligand. In the crystal, hydrogen bonding (water–acetate/perchlorate O—H⋯O and amine–perchlorate N—H⋯O) leads to layers in the ab plane. The layers stack along the c axis, being connected by C—H⋯O(water) interactions. The crystal studied was found to be a non-merohedral twin; the minor component refined to 15.9 (6)%.

The complete cation in the title hydrated molecular salt, [Ni(CH 3 CO 2 )(C 16 H 36 N 4 )]ClO 4 ÁH 2 O, is generated by the application of crystallographic twofold symmetry; the perchlorate anion and water molecule are each disordered around a twofold axis. The Ni II atom exists within a cis-N 4 O 2 donor set based on a strongly distorted octahedron and defined by the four N atoms of the macrocyclic ligand and two O atoms of a symmetrically coordinating acetate ligand. In the crystal, hydrogen bonding (water-acetate/perchlorate O-HÁ Á ÁO and amine-perchlorate N-HÁ Á ÁO) leads to layers in the ab plane. The layers stack along the c axis, being connected by C-HÁ Á ÁO(water) interactions. The crystal studied was found to be a non-merohedral twin; the minor component refined to 15.9 (6)%.

Related literature
For background to macrocyclic complexes, see: Hazari et al. (2010). For a related structure, see: Roy et al. (2012). For the treatment of data from twinned crystals, see: Spek (2009).
The asymmetric unit of (I) comprises half a NiL(O 2 CMe) cation, Fig. 1, as this is has crystallographic twofold symmetry, half a perchlorate anion (this is disordered about a twofold axis) and half a water molecule of solvation (this is also disordered about a twofold axis); where L is 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane. The Ni II atom exists within a cis-N 4 O 2 donor set defined by the four N atoms of the macrocyclic ligand and two acetate-O atoms, Table 1. The coordination geometry is based on an octahedron. There are significant distortions from the ideal geometry owing in part to the restricted bite angle of the acetate ligand as manifested in the O1-Ni-O1 i angle of 62.28 (13)°; symmetry operation i: 1 -x, y, 3/2 -z. In particular, this bite angle restricts the putative trans O1-Ni-O1 angle to 158.84 (12)°; the N2-Ni-N2 i angle = 175.92 (17)°.
In the crystal packing, the water molecule forms O-H···O hydrogen bonds to the acetate-O1 and perchlorate-O2 atoms, while the amine-H atoms form hydrogen bonds to perchlorate-O atoms; the N1-H atom is bifurcated, Table 2. The hydrogen bonding leads to layers in the ab plane, Fig. 2. Layers are connected along the c axis by C-H···O(water) interactions, Fig. 3 and Table 2.

Experimental
The title complex, (I), was prepared by the anion exchange reaction of [NiL(O 2 CMe)][O 2 CMe] with perchlorate, where L is 5, 5,7,12,12,4,8,[NiL(O 2 CMe)][O 2 CMe] (0.495 g, 1.0 mmol) was dissolved in hot methanol (40 ml) and sodium perchlorate hexahydrate (0.460 g, 2.0 mmol) added. The reaction mixture was heated for 15 min. During heating a blue product separated out. After cooling at room temperature for 30 min, the product, (I), was filtered off, washed with methanol followed by diethyl ether and dried in a desiccator over silica-gel.
Light-purple prisms of (I) were obtained from slow evaporation of its methanol solution. Yield 65%. M.pt: 512-513 K.
Finally, the methyl-H atoms of the acetate group are disordered over two positions of equal weight. The crystal studied is a non-merohedral twin. The twin domains were separated by the TwinRotMat routine in PLATON (Spek, 2009). The minor component refined to 15.9 (6)%.

Special details
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.