trans-Di­aqua(C-meso-5,12-di­methyl-1,4,8,11-tetra­aza­cyclo­tetra­decane-N,N',N'',N''')copper(II) dichloride dihydrate

The crystal structure of the title complex, [Cu(C₁₂H₂₈N₄)(H₂O)₂]Cl₂·2H₂O, has been determined. The Cu^II atom is octahedrally coordinated by the four N atoms of the tetradentate macrocyclic ligand in equatorial positions and by the O atoms of two water mol­ecules in axial positions. The crystal structure is stabilized by a three-dimensional network of hydrogen bonds.

S1. Comment

The macrocyclic ligand 5,12-dimethyl-1,4,8,11-tetraazacyclotetradecane exists as two isomers, i.e. C-meso and C-rac. The coordination behaviour of transition metal complexes of C-meso- and C-rac-5,12-dimethyl-1,4,8,11-tetraazacyclotetradecane has been widely studied (Chen et al., 1994; Hay et al., 1984; Hay & Govan, 1992; Hay & Piplani, 1977). The crystal structures of complexes of the C-rac isomer with Cu^II and Co^III have been reported previously (Panneerselvam et al., 1999; Tahirov et al., 1994). The present paper reports the crystal structure of the copper(II) complex of the C-meso isomer, (I).

The Cu^II ion is six-coordinated in a distorted octahedral geometry with the four N atoms of the macrocyclic ligand in equatorial positions and two O atoms of two water molecules in axial positions. This compound is not a symmetric complex, since the two trans water molecules and the four N atoms of the tetradentate ligand are coordinated at different distances. In the majority of monomeric trans-diaquacopper(II) complexes, the Cu atom is located at a center of symmetry or on a twofold axis (Allen & Kennard, 1993). There are only a few examples where the trans-diaquacopper(II) octahedral complex is not centrosymmetric (Kozhemyak et al., 1980; Biagini Cingi et al., 1989; Petrovčič et al., 1999).

The Cu^II ion and the four N-donor atoms are coplanar within 0.004 (1) Å. The Cu—N distances are in the range 1.997 (2)–2.047 (2) Å and the average Cu—N distance, 2.023 (2) Å, is similar to the average Cu—N distance found for Cu^II tetraaza macrocyclic complexes [2.03 (3) Å; Lu et al., 1991]. The Cu—O_water distances, 2.542 (2) and 2.505 (2) Å, are shorter than those found in trans-diaquacopper(II) tetraaza macrocyclic complexes of the type trans-[Cu(C-meso-1,5,8,12-tetramethyl-1,4,8,11-tetraazacyclotetradecane)- (OH₂)₂]X₂, i.e. 2.624 (3) Å for X = NO₂, 2.692 (2) Å for X = Cl, 2.695 (16) Å for X = Br and 2.725 (3) Å for X = I (Lu et al., 1999). The tetradentate ligand adopts a conformation with two six-membered rings in a chair form and two five-membered rings in a gauche form. The arrangement of the four chiral nitrogen centers is in the type-III configuration designated by Bosnich et al. (1965). The two C-methyl groups occupy equatorial positions. The complex has a 1SR,4RS,8RS,11SR configuration for the four chiral N-atom centers and a 5SR,12RS configuration for the two chiral C-atom centers. The crystal structure is stabilized by hydrogen bonds (Table 2).

S2. Experimental

The ligand C-meso-5,12-dimethyl-1,4,8,11-tetraazacyclotetradecane was prepared according to Hay & Piplani (1977). Equimolar quantities of copper(II) sulfate pentahydrate and C-meso-5,12-dimethyl-1,4,8,11-tetraazacyclotetradecane were dissolved in water and left to react for ca 30 min in a steam bath. The resulting solution was evaporated to dryness by rotatory evaporation. The crystals were obtained from 2 M NaCl aqueous solution on slow evaporation.

Computing details

Data collection: CAD-4 Software (Enraf-Nonius, 1989); cell refinement: CAD-4 Software; data reduction: NRCVAX (Gabe et al., 1989); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: NRCVAX; software used to prepare material for publication: SHELXL97.

Figures

Fig. 1. The structure of the title compound showing 30% probability displacement ellipsoids. The chloride anions, the uncoordinated water molecules and the H atoms have been omitted for clarity.

trans-Diaqua(C-meso-5,12-dimethyl-1,4,8,11- tetraazacyclotetradecane-N,N',N'',N''')copper(II) dichloride dihydrate

Crystal data

[Cu(C12H28N4)(H2O)2]Cl2·2H2O	F(000) = 924
Mr = 434.89	Dx = 1.380 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 8.043 (1) Å	Cell parameters from 25 reflections
b = 17.482 (4) Å	θ = 9.4–17.3°
c = 15.237 (3) Å	µ = 1.32 mm^−1
β = 102.30 (1)°	T = 293 K
V = 2093.4 (7) Å^3	Pillar, blue
Z = 4	0.38 × 0.31 × 0.28 mm

Data collection

Enraf-Nonius CAD-4 diffractometer	2947 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.028
Graphite monochromator	θmax = 25°, θmin = 1.8°
ω/2θ scans	h = 0→9
Absorption correction: ψ scan (North et al., 1968)	k = −20→20
Tmin = 0.619, Tmax = 0.691	l = −18→17
7942 measured reflections	3 standard reflections every 60 min
3688 independent reflections	intensity decay: 1%

Refinement

Refinement on F^2	Primary atom site location: heavy-atom method
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.028	Hydrogen site location: mixed
wR(F^2) = 0.076	H-atom parameters constrained
S = 1.02	w = 1/[σ^2(Fo^2) + (0.0394P)^2 + 0.3263P] where P = (Fo^2 + 2Fc^2)/3
3688 reflections	(Δ/σ)max = 0.002
210 parameters	Δρmax = 0.39 e Å^−3
0 restraints	Δρmin = −0.31 e Å^−3

Special details

Experimental. The maximum 2θ for data collection is 50.0°. The data collection would not go beyond this limit, because of the crystal quality.

Refinement. The H atoms were fixed geometrically and water H atoms were located from the difference-Fourier map.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Cu1	0.44739 (3)	0.74283 (1)	0.83515 (1)	0.0343 (1)
O1	0.2851 (2)	0.75121 (10)	0.96090 (11)	0.0634 (5)
H1O1	0.3186	0.7139	0.9995	0.080*
H2O1	0.2728	0.7907	0.9936	0.080*
O2	0.6086 (2)	0.74014 (10)	0.71150 (11)	0.0608 (4)
H1O2	0.5873	0.7819	0.6749	0.080*
H2O2	0.6377	0.7082	0.6823	0.080*
N1	0.2727 (2)	0.66922 (11)	0.77006 (11)	0.0468 (4)
H1N1	0.2944	0.6628	0.7143	0.056*
N2	0.5721 (2)	0.64784 (10)	0.89347 (11)	0.0446 (4)
H1N2	0.5454	0.6432	0.9483	0.054*
N3	0.6204 (2)	0.81596 (10)	0.90132 (11)	0.0432 (4)
H1N3	0.5963	0.8228	0.9565	0.052*
N4	0.3205 (2)	0.83762 (11)	0.77679 (11)	0.0456 (4)
H1N4	0.3465	0.8420	0.7217	0.055*
C1	0.3048 (4)	0.59523 (14)	0.81591 (18)	0.0672 (8)
H1A	0.2497	0.5547	0.7769	0.081*
H1B	0.2591	0.5954	0.8699	0.081*
C2	0.4930 (4)	0.58199 (13)	0.83966 (17)	0.0646 (7)
H2A	0.5180	0.5351	0.8740	0.078*
H2B	0.5374	0.5774	0.7855	0.078*
C3	0.7617 (3)	0.64786 (16)	0.90960 (17)	0.0597 (7)
H3	0.7945	0.6511	0.8514	0.072*
C4	0.8321 (3)	0.71707 (19)	0.96464 (17)	0.0674 (8)
H4A	0.7828	0.7190	1.0174	0.081*
H4B	0.9540	0.7104	0.9852	0.081*
C5	0.8003 (3)	0.79279 (17)	0.91627 (18)	0.0619 (7)
H5A	0.8705	0.8318	0.9514	0.074*
H5B	0.8334	0.7889	0.8588	0.074*
C6	0.5887 (3)	0.88993 (13)	0.85394 (17)	0.0574 (6)
H6A	0.6350	0.8890	0.8002	0.069*
H6B	0.6437	0.9308	0.8924	0.069*
C7	0.4007 (4)	0.90353 (13)	0.82935 (17)	0.0598 (7)
H7A	0.3558	0.9093	0.8832	0.072*
H7B	0.3767	0.9500	0.7941	0.072*
C8	0.1313 (3)	0.83803 (17)	0.76081 (16)	0.0629 (7)
H8	0.0991	0.8362	0.8193	0.075*
C9	0.0598 (3)	0.7674 (2)	0.70815 (19)	0.0746 (9)
H9A	−0.0623	0.7737	0.6887	0.090*
H9B	0.1067	0.7646	0.6546	0.090*
C10	0.0935 (3)	0.69282 (18)	0.75715 (18)	0.0682 (8)
H1OA	0.0635	0.6975	0.8153	0.082*
H10B	0.0217	0.6536	0.7235	0.082*
C11	0.8368 (5)	0.5742 (2)	0.9563 (2)	0.1062 (13)
H11A	0.7999	0.5684	1.0118	0.127*
H11B	0.9587	0.5769	0.9682	0.127*
H11C	0.7987	0.5312	0.9181	0.127*
C12	0.0548 (5)	0.9100 (2)	0.7124 (2)	0.1045 (13)
H12A	0.0923	0.9539	0.7493	0.125*
H12B	−0.0671	0.9069	0.7009	0.125*
H12C	0.0910	0.9148	0.6565	0.125*
Cl1	0.45811 (13)	0.87780 (4)	0.58995 (4)	0.0885 (3)
Cl2	0.23711 (8)	0.59497 (4)	0.56513 (4)	0.06240 (18)
O3	0.6291 (2)	0.87627 (11)	1.09328 (13)	0.0740 (5)
H1O3	0.7050	0.9100	1.0866	0.080*
H2O3	0.5040	0.9023	1.0761	0.080*
O4	0.1110 (3)	0.47642 (12)	0.40706 (13)	0.0786 (6)
H1O4	0.0277	0.4507	0.4186	0.080*
H2O4	0.1505	0.5135	0.4563	0.080*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.0348 (1)	0.0358 (1)	0.0323 (1)	−0.0024 (1)	0.0068 (1)	−0.0010 (1)
O1	0.0760 (12)	0.0708 (12)	0.0465 (9)	0.0042 (9)	0.0202 (9)	−0.0031 (8)
O2	0.0714 (11)	0.0691 (11)	0.0463 (9)	0.0036 (9)	0.0229 (8)	−0.0038 (8)
N1	0.0460 (11)	0.0600 (12)	0.0365 (9)	−0.0149 (9)	0.0132 (8)	−0.0098 (8)
N2	0.0576 (11)	0.0450 (10)	0.0331 (9)	0.0086 (8)	0.0136 (8)	0.0029 (7)
N3	0.0437 (10)	0.0494 (10)	0.0387 (9)	−0.0092 (8)	0.0139 (8)	−0.0108 (8)
N4	0.0526 (11)	0.0522 (11)	0.0355 (9)	0.0121 (9)	0.0169 (8)	0.0063 (8)
C1	0.090 (2)	0.0501 (14)	0.0628 (16)	−0.0305 (14)	0.0202 (15)	−0.0090 (12)
C2	0.104 (2)	0.0356 (12)	0.0562 (15)	0.0018 (13)	0.0209 (15)	−0.0003 (11)
C3	0.0541 (15)	0.0768 (18)	0.0478 (13)	0.0260 (13)	0.0101 (11)	0.0034 (12)
C4	0.0399 (13)	0.108 (2)	0.0507 (14)	0.0140 (14)	0.0003 (11)	−0.0032 (15)
C5	0.0368 (13)	0.0854 (19)	0.0630 (15)	−0.0129 (13)	0.0096 (11)	−0.0197 (14)
C6	0.0795 (18)	0.0422 (12)	0.0564 (14)	−0.0207 (12)	0.0274 (13)	−0.0089 (11)
C7	0.091 (2)	0.0371 (12)	0.0569 (15)	0.0105 (12)	0.0289 (14)	0.0039 (10)
C8	0.0519 (15)	0.092 (2)	0.0446 (13)	0.0292 (14)	0.0103 (11)	0.0060 (13)
C9	0.0398 (14)	0.130 (3)	0.0497 (15)	0.0120 (15)	−0.0005 (11)	−0.0073 (17)
C10	0.0412 (14)	0.106 (2)	0.0585 (15)	−0.0223 (14)	0.0127 (12)	−0.0212 (16)
C11	0.110 (3)	0.106 (3)	0.094 (2)	0.060 (2)	0.001 (2)	0.016 (2)
C12	0.102 (3)	0.128 (3)	0.078 (2)	0.065 (2)	0.0076 (19)	0.023 (2)
Cl1	0.1804 (10)	0.0481 (4)	0.0508 (4)	−0.0025 (4)	0.0553 (5)	−0.0022 (3)
Cl2	0.0678 (4)	0.0620 (4)	0.0600 (4)	−0.0188 (3)	0.0194 (3)	−0.0117 (3)
O3	0.0685 (12)	0.0704 (12)	0.0865 (13)	0.0016 (10)	0.0243 (11)	0.0129 (10)
O4	0.0739 (12)	0.0824 (13)	0.0899 (14)	−0.0217 (11)	0.0410 (11)	−0.0296 (11)

Geometric parameters (Å, º)

Cu1—O1	2.542 (2)	C3—H3	0.98
Cu1—O2	2.505 (2)	C4—C5	1.510 (4)
Cu1—N3	1.997 (2)	C4—H4A	0.97
Cu1—N1	2.005 (2)	C4—H4B	0.97
Cu1—N2	2.043 (2)	C5—H5A	0.97
Cu1—N4	2.047 (2)	C5—H5B	0.97
O1—H1O1	0.88	C6—C7	1.497 (4)
O1—H2O1	0.86	C6—H6A	0.97
O2—H1O2	0.91	C6—H6B	0.97
O2—H2O2	0.78	C7—H7A	0.97
N1—C1	1.467 (3)	C7—H7B	0.97
N1—C10	1.472 (3)	C8—C9	1.518 (4)
N1—H1N1	0.91	C8—C12	1.521 (4)
N2—C2	1.477 (3)	C8—H8	0.98
N2—C3	1.492 (3)	C9—C10	1.498 (4)
N2—H1N2	0.91	C9—H9A	0.97
N3—C5	1.473 (3)	C9—H9B	0.97
N3—C6	1.476 (3)	C10—H1OA	0.97
N3—H1N3	0.91	C10—H10B	0.97
N4—C7	1.471 (3)	C11—H11A	0.96
N4—C8	1.489 (3)	C11—H11B	0.96
N4—H1N4	0.91	C11—H11C	0.96
C1—C2	1.497 (4)	C12—H12A	0.96
C1—H1A	0.97	C12—H12B	0.96
C1—H1B	0.97	C12—H12C	0.96
C2—H2A	0.97	O3—H1O3	0.87
C2—H2B	0.97	O3—H2O3	1.08
C3—C4	1.512 (4)	O4—H1O4	0.85
C3—C11	1.531 (4)	O4—H2O4	0.99
O1—Cu1—O2	177.77 (6)	C11—C3—H3	108.3
N1—Cu1—O1	89.51 (7)	C5—C4—C3	115.2 (2)
N2—Cu1—O1	90.13 (6)	C5—C4—H4A	108.5
N3—Cu1—O1	89.83 (7)	C3—C4—H4A	108.5
N4—Cu1—O1	89.56 (6)	C5—C4—H4B	108.5
N1—Cu1—O2	92.09 (7)	C3—C4—H4B	108.5
N2—Cu1—O2	91.55 (7)	H4A—C4—H4B	107.5
N3—Cu1—O2	88.58 (7)	N3—C5—C4	112.0 (2)
N4—Cu1—O2	88.77 (7)	N3—C5—H5A	109.2
N3—Cu1—N1	179.31 (7)	C4—C5—H5A	109.2
N3—Cu1—N2	94.36 (8)	N3—C5—H5B	109.2
N1—Cu1—N2	85.45 (8)	C4—C5—H5B	109.2
N3—Cu1—N4	86.00 (8)	H5A—C5—H5B	107.9
N1—Cu1—N4	94.18 (8)	N3—C6—C7	108.75 (19)
N2—Cu1—N4	179.52 (8)	N3—C6—H6A	109.9
H1O1—O1—H2O1	105.1	C7—C6—H6A	109.9
H1O2—O2—H2O2	105.3	N3—C6—H6B	109.9
C1—N1—C10	112.3 (2)	C7—C6—H6B	109.9
C1—N1—Cu1	107.26 (14)	H6A—C6—H6B	108.3
C10—N1—Cu1	116.71 (16)	N4—C7—C6	108.29 (19)
C1—N1—H1N1	106.7	N4—C7—H7A	110.0
C10—N1—H1N1	106.7	C6—C7—H7A	110.0
Cu1—N1—H1N1	106.7	N4—C7—H7B	110.0
C2—N2—C3	113.3 (2)	C6—C7—H7B	110.0
C2—N2—Cu1	106.19 (14)	H7A—C7—H7B	108.4
C3—N2—Cu1	117.47 (16)	N4—C8—C9	110.0 (2)
C2—N2—H1N2	106.4	N4—C8—C12	112.2 (3)
C3—N2—H1N2	106.4	C9—C8—C12	110.4 (2)
Cu1—N2—H1N2	106.4	N4—C8—H8	108.1
C5—N3—C6	112.2 (2)	C9—C8—H8	108.1
C5—N3—Cu1	117.24 (15)	C12—C8—H8	108.1
C6—N3—Cu1	106.53 (14)	C10—C9—C8	115.9 (2)
C5—N3—H1N3	106.8	C10—C9—H9A	108.3
C6—N3—H1N3	106.8	C8—C9—H9A	108.3
Cu1—N3—H1N3	106.8	C10—C9—H9B	108.3
C7—N4—C8	113.5 (2)	C8—C9—H9B	108.3
C7—N4—Cu1	106.11 (14)	H9A—C9—H9B	107.4
C8—N4—Cu1	118.18 (16)	N1—C10—C9	112.2 (2)
C7—N4—H1N4	106.1	N1—C10—H1OA	109.2
C8—N4—H1N4	106.1	C9—C10—H1OA	109.2
Cu1—N4—H1N4	106.1	N1—C10—H10B	109.2
N1—C1—C2	108.5 (2)	C9—C10—H10B	109.2
N1—C1—H1A	110.0	H1OA—C10—H10B	107.9
C2—C1—H1A	110.0	C3—C11—H11A	109.5
N1—C1—H1B	110.0	C3—C11—H11B	109.5
C2—C1—H1B	110.0	H11A—C11—H11B	109.5
H1A—C1—H1B	108.4	C3—C11—H11C	109.5
N2—C2—C1	107.9 (2)	H11A—C11—H11C	109.5
N2—C2—H2A	110.1	H11B—C11—H11C	109.5
C1—C2—H2A	110.1	C8—C12—H12A	109.5
N2—C2—H2B	110.1	C8—C12—H12B	109.5
C1—C2—H2B	110.1	H12A—C12—H12B	109.5
H2A—C2—H2B	108.4	C8—C12—H12C	109.5
N2—C3—C4	109.9 (2)	H12A—C12—H12C	109.5
N2—C3—C11	111.4 (3)	H12B—C12—H12C	109.5
C4—C3—C11	110.5 (2)	H1O3—O3—H2O3	109.0
N2—C3—H3	108.3	H1O4—O4—H2O4	109.0
C4—C3—H3	108.3
Cu1—N1—C1—C2	−41.3 (2)	C6—C7—N4—Cu1	39.1 (2)
N1—C1—C2—N2	55.6 (3)	C7—N4—Cu1—N3	−12.9 (1)
C1—C2—N2—Cu1	−40.6 (2)	N4—Cu1—N3—C6	−15.9 (1)
C2—N2—Cu1—N1	14.5 (2)	Cu1—N4—C8—C9	−53.5 (2)
N2—Cu1—N1—C1	14.7 (2)	N4—C8—C9—C10	68.9 (3)
Cu1—N2—C3—C4	55.3 (2)	C8—C9—C10—N1	−72.0 (3)
N2—C3—C4—C5	−70.3 (3)	C9—C10—N1—Cu1	57.1 (3)
C3—C4—C5—N3	71.5 (3)	C10—N1—Cu1—N4	−38.1 (2)
C4—C5—N3—Cu1	−56.1 (2)	N1—Cu1—N4—C8	37.6 (2)
C5—N3—Cu1—N2	37.8 (2)	C2—N2—C3—C11	−57.4 (3)
N3—Cu1—N2—C3	−38.1 (2)	C11—C3—C4—C5	166.3 (2)
Cu1—N3—C6—C7	42.1 (2)	C7—N4—C8—C12	58.0 (3)
N3—C6—C7—N4	−55.4 (2)	C12—C8—C9—C10	−166.8 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N1···Cl2	0.91	2.52	3.337 (2)	150
N2—H1N2···Cl1^i	0.91	2.44	3.343 (2)	175
N3—H1N3···O3	0.91	2.25	3.096 (3)	155
N4—H1N4···Cl1	0.91	2.49	3.341 (2)	167
O1—H1O1···Cl1^i	0.88	2.25	3.118 (2)	168
O1—H2O1···Cl2^i	0.87	2.32	3.188 (2)	173
O2—H1O2···Cl1	0.91	2.23	3.120 (2)	163
O2—H2O2···O3^ii	0.78	2.00	2.746 (3)	161
O3—H1O3···O4^iii	0.87	1.87	2.728 (3)	170
O3—H2O3···Cl2^i	1.08	2.12	3.131 (2)	154
O4—H1O4···Cl2^iv	0.85	2.34	3.175 (2)	167
O4—H2O4···Cl2	0.99	2.18	3.175 (2)	180

Symmetry codes: (i) x, −y+3/2, z+1/2; (ii) x, −y+3/2, z−1/2; (iii) −x+1, y+1/2, −z+3/2; (iv) −x, −y+1, −z+1.