The short carbonyl bond in the title compound, [Cu2(C7H4NO3S)4(C3H4N2)4] [Liu, Huang, Li & Lin (1991). Acta Cryst. C47, 41–43], is an artifact of disorder in the isothiazol-3(2H)-one 1,1-dioxide part of the 1,2-benzisothiazol-3(2H)-one entity. In the present redetermination, all bond dimensions in the centrosymmetric dinuclear molecule are normal. The five-coordinate Cu atom shows trigonal–bipyramidal coordination. Hydrogen bonds from the imidazole donor ligand link adjacent molecules into a two-dimensional layer structure.
Supporting information
CCDC reference: 173340
Tetraaquabis(saccharinato)copper dihydrate was synthesized from copper(II)
nitrate and sodium saccharinate in water. Lilac-coloured crystals of (I) were
grown from an aqueous mixture of the copper complex and imidazole in a 1:2
molar ratio. Elemental (C, H, N, S) analysis, 1H NMR and UV-vis
spectroscopic measurements, and thermal analyses all confirmed the composition
as [Cu2(C7H4SO3N)4(C3H4N2)4]. For the density functional
theory (DFT) quantum-chemical calculations, the global minimum of an isolated
saccharinate molecule in its ground electronic state was located using a
stepwise unrestricted optimization procedure in which the energy derivatives
up to the B3LYP/6–31++G(d,p) level (Becke, 1993) were computed analytically
with the GAUSSIAN98 program suite (Frisch et al., 1998) running
on an ORIGIN2000 supercomputer. Harmonic vibrational analysis at the same
level confirmed that the stationary point represented a minimum. The
computations were repeated with the deviant C—O distance frozen at 1.103 Å, which is the distance given in the earlier report (Liu et al.,
1991).
One of the two 1,2-benzisothiazol-3(2H)-one 1,1-dioxide anions is
disordered in the sulfonyl (SO2) and carbonyl (CO) groups; the ratio of the
occupancy of the major (unprimed) to the minor (primed) components refined to
7:1. The sulfonyl and carbonyl groups are disordered across a pseudo mirror
plane. A number of restraints were applied to treat the disorder: the
displacement parameters of atom S1 were set equal to those of atom C7' and
those of atom S1' equal to those of atom C7. The displacement parameters of
the unprimed O atoms were set equal to those of the primed O atoms.
1,2-Related and 1,3-related bond distances involving atoms S1, C7 and O1 were
restrained to be equal to those of the corresponding primed atoms by SADI
0.005 and SADI 0.010 instructions in SHELXL97 (Sheldrick, 1997). A
larger deviation in the SADI instructions gave somewhat unsatisfactory angles
at the minor carbonyl C atom. The isothiazolyl C5—C6—C7(S1')-N1—S1(C7')
unit (r.m.s. deviation 0.020 Å) was restrained to be flat by a FLAT 0.01
instruction. The 1,2-phenylene ring (r.m.s. deviation 0.004 Å) is coplanar
with this unit [dihedral angle 2.5 (2)°] and it is not spilt into two
components. H atoms were treated as riding, with C—H = 0.93 and N—H = 0.86 Å, and with Uiso(H) equal to 1.2 times Ueq of the parent
atom. Query.
Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97.
Bis[µ-1,2-benzisothiazol-3(2
H)-one
1,1-dioxido-
κN:
κO]bis{[1,2-benzisothiazol-3(2
H)-one
1,1-dixoido-
κN]bis(imidazole)copper(II)}
top
Crystal data top
[Cu2(C7H4NO3S)4(C3H4N2)4] | F(000) = 1148 |
Mr = 1128.10 | Dx = 1.717 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
a = 11.1176 (1) Å | Cell parameters from 8192 reflections |
b = 11.5112 (1) Å | θ = 2.1–28.3° |
c = 17.1203 (1) Å | µ = 1.25 mm−1 |
β = 95.346 (1)° | T = 298 K |
V = 2181.47 (3) Å3 | Parallelepiped, blue |
Z = 2 | 0.44 × 0.36 × 0.24 mm |
Data collection top
Siemens CCD area-detector diffractometer | 5330 independent reflections |
Radiation source: fine-focus sealed tube | 4073 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.068 |
ω scan | θmax = 28.3°, θmin = 2.1° |
Absorption correction: empirical (using intensity measurements) (SADABS; Sheldrick, 1996) | h = −14→14 |
Tmin = 0.610, Tmax = 0.754 | k = −13→15 |
15502 measured reflections | l = −16→22 |
Refinement top
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.051 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.139 | H-atom parameters constrained |
S = 0.98 | w = 1/[σ2(Fo2) + (0.0821P)2] where P = (Fo2 + 2Fc2)/3 |
5330 reflections | (Δ/σ)max < 0.001 |
332 parameters | Δρmax = 0.65 e Å−3 |
16 restraints | Δρmin = −1.24 e Å−3 |
Crystal data top
[Cu2(C7H4NO3S)4(C3H4N2)4] | V = 2181.47 (3) Å3 |
Mr = 1128.10 | Z = 2 |
Monoclinic, P21/n | Mo Kα radiation |
a = 11.1176 (1) Å | µ = 1.25 mm−1 |
b = 11.5112 (1) Å | T = 298 K |
c = 17.1203 (1) Å | 0.44 × 0.36 × 0.24 mm |
β = 95.346 (1)° | |
Data collection top
Siemens CCD area-detector diffractometer | 5330 independent reflections |
Absorption correction: empirical (using intensity measurements) (SADABS; Sheldrick, 1996) | 4073 reflections with I > 2σ(I) |
Tmin = 0.610, Tmax = 0.754 | Rint = 0.068 |
15502 measured reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.051 | 16 restraints |
wR(F2) = 0.139 | H-atom parameters constrained |
S = 0.98 | Δρmax = 0.65 e Å−3 |
5330 reflections | Δρmin = −1.24 e Å−3 |
332 parameters | |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | Occ. (<1) |
Cu1 | 0.14122 (3) | 0.15548 (3) | 0.04009 (2) | 0.0225 (1) | |
S1 | 0.32211 (8) | 0.34788 (7) | 0.12327 (5) | 0.0285 (3) | 0.870 (3) |
S1' | 0.3897 (5) | 0.2427 (4) | −0.0156 (3) | 0.0342 (9) | 0.130 (3) |
S2 | 0.02090 (7) | −0.23445 (7) | −0.17712 (5) | 0.0327 (2) | |
O1 | 0.3807 (3) | 0.1990 (3) | −0.0588 (2) | 0.0469 (8) | 0.870 (3) |
O1' | 0.259 (1) | 0.388 (2) | 0.143 (1) | 0.0469 (8) | 0.13 |
O2 | 0.2457 (2) | 0.4488 (3) | 0.1221 (2) | 0.0492 (8) | 0.870 (3) |
O2' | 0.362 (2) | 0.280 (2) | −0.0950 (5) | 0.0492 (8) | 0.13 |
O3 | 0.3268 (3) | 0.2815 (3) | 0.1942 (2) | 0.0465 (8) | 0.870 (3) |
O3' | 0.444 (2) | 0.1295 (9) | −0.008 (1) | 0.0465 (8) | 0.13 |
O4 | 0.1159 (2) | 0.0132 (2) | −0.0522 (1) | 0.0321 (5) | |
O5 | 0.0174 (3) | −0.3510 (2) | −0.1472 (2) | 0.0590 (8) | |
O6 | −0.0632 (2) | −0.2112 (3) | −0.2444 (2) | 0.0516 (7) | |
N2 | 0.0061 (2) | −0.1388 (2) | −0.1087 (1) | 0.0248 (5) | |
N3 | 0.0449 (2) | 0.2563 (2) | −0.0345 (1) | 0.0250 (5) | |
N4 | −0.0295 (3) | 0.4081 (2) | −0.0967 (2) | 0.0362 (6) | |
N5 | 0.2372 (2) | 0.0395 (2) | 0.1023 (1) | 0.0260 (5) | |
N6 | 0.3116 (3) | −0.0751 (3) | 0.1953 (2) | 0.0398 (7) | |
N1 | 0.2894 (2) | 0.2643 (2) | 0.0466 (1) | 0.0251 (5) | |
C1 | 0.6039 (4) | 0.3383 (3) | 0.0067 (3) | 0.052 (1) | |
C2 | 0.6902 (4) | 0.4036 (4) | 0.0483 (3) | 0.059 (1) | |
C3 | 0.6646 (4) | 0.4632 (4) | 0.1129 (3) | 0.058 (1) | |
C4 | 0.5505 (4) | 0.4558 (4) | 0.1424 (2) | 0.052 (1) | |
C5 | 0.4650 (2) | 0.3813 (2) | 0.1013 (2) | 0.0315 (7) | |
C6 | 0.4940 (2) | 0.3289 (2) | 0.0341 (2) | 0.0289 (6) | |
C7 | 0.3865 (4) | 0.2570 (3) | 0.0018 (3) | 0.0342 (9) | 0.870 (3) |
C7' | 0.3352 (7) | 0.3379 (5) | 0.1072 (5) | 0.0285 (3) | 0.13 |
C8 | 0.3163 (3) | −0.0542 (3) | −0.1529 (2) | 0.0333 (7) | |
C9 | 0.3908 (3) | −0.1053 (4) | −0.2046 (2) | 0.0446 (9) | |
C10 | 0.3546 (3) | −0.1978 (3) | −0.2504 (2) | 0.0446 (9) | |
C11 | 0.2395 (3) | −0.2446 (3) | −0.2490 (2) | 0.0401 (8) | |
C12 | 0.1674 (3) | −0.1960 (3) | −0.1969 (2) | 0.0285 (6) | |
C13 | 0.2029 (2) | −0.1026 (2) | −0.1496 (2) | 0.0233 (6) | |
C14 | 0.1059 (2) | −0.0675 (2) | −0.0987 (2) | 0.0222 (6) | |
C15 | 0.0601 (3) | 0.3673 (3) | −0.0477 (2) | 0.0322 (7) | |
C16 | −0.1069 (3) | 0.3189 (3) | −0.1166 (2) | 0.0386 (8) | |
C17 | −0.0601 (3) | 0.2259 (3) | −0.0782 (2) | 0.0362 (8) | |
C18 | 0.2286 (3) | 0.0059 (3) | 0.1748 (2) | 0.0321 (7) | |
C19 | 0.3775 (3) | −0.0939 (3) | 0.1342 (2) | 0.0380 (8) | |
C20 | 0.3314 (3) | −0.0218 (3) | 0.0766 (2) | 0.0348 (7) | |
H4N | −0.0374 | 0.4786 | −0.1131 | 0.043* | |
H6N | 0.3214 | −0.1096 | 0.2400 | 0.048* | |
H1 | 0.6203 | 0.3012 | −0.0394 | 0.062* | |
H2 | 0.7676 | 0.4073 | 0.0320 | 0.071* | |
H3 | 0.7238 | 0.5102 | 0.1385 | 0.070* | |
H4 | 0.5325 | 0.4974 | 0.1864 | 0.062* | |
H8 | 0.3417 | 0.0093 | −0.1221 | 0.040* | |
H9 | 0.4678 | −0.0751 | −0.2078 | 0.053* | |
H10 | 0.4077 | −0.2301 | −0.2833 | 0.053* | |
H11 | 0.2128 | −0.3058 | −0.2817 | 0.048* | |
H15 | 0.1247 | 0.4114 | −0.0257 | 0.039* | |
H16 | −0.1777 | 0.3221 | −0.1501 | 0.046* | |
H17 | −0.0935 | 0.1518 | −0.0808 | 0.043* | |
H18 | 0.1728 | 0.0344 | 0.2072 | 0.039* | |
H19 | 0.4414 | −0.1457 | 0.1321 | 0.046* | |
H20 | 0.3594 | −0.0150 | 0.0273 | 0.042* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Cu1 | 0.0186 (2) | 0.0212 (2) | 0.0267 (2) | −0.0012 (1) | −0.0030 (1) | 0.0045 (1) |
S1 | 0.0192 (4) | 0.0337 (5) | 0.0330 (5) | −0.0023 (3) | 0.0040 (3) | −0.0081 (3) |
S1' | 0.037 (1) | 0.04 (3) | 0.028 (2) | −0.018 (1) | −0.006 (1) | 0.000 (2) |
S2 | 0.0263 (4) | 0.0283 (4) | 0.0447 (5) | −0.0099 (3) | 0.0094 (3) | −0.0138 (3) |
O1 | 0.042 (2) | 0.056 (2) | 0.044 (2) | −0.021 (2) | 0.014 (1) | −0.026 (2) |
O1' | 0.042 (2) | 0.056 (2) | 0.044 (2) | −0.021 (2) | 0.014 (1) | −0.026 (2) |
O2 | 0.029 (1) | 0.041 (2) | 0.077 (2) | 0.011 (1) | 0.003 (1) | −0.018 (2) |
O2' | 0.029 (1) | 0.041 (2) | 0.077 (2) | 0.011 (1) | 0.003 (1) | −0.018 (2) |
O3 | 0.049 (2) | 0.063 (2) | 0.028 (2) | −0.014 (2) | 0.008 (1) | −0.001 (1) |
O3' | 0.049 (2) | 0.063 (2) | 0.028 (2) | −0.014 (2) | 0.008 (1) | −0.001 (1) |
O4 | 0.033 (1) | 0.032 (1) | 0.031 (1) | −0.005 (1) | 0.000 (1) | −0.013 (1) |
O5 | 0.064 (2) | 0.026 (1) | 0.092 (2) | −0.020 (1) | 0.035 (2) | −0.013 (1) |
O6 | 0.034 (2) | 0.069 (2) | 0.050 (2) | −0.008 (1) | −0.006 (1) | −0.032 (1) |
N2 | 0.022 (1) | 0.027 (1) | 0.026 (1) | −0.002 (1) | 0.004 (1) | −0.004 (1) |
N3 | 0.021 (1) | 0.023 (1) | 0.029 (1) | −0.001 (1) | −0.004 (1) | 0.004 (1) |
N4 | 0.045 (2) | 0.024 (1) | 0.039 (2) | 0.007 (1) | −0.006 (1) | 0.008 (1) |
N5 | 0.023 (1) | 0.024 (1) | 0.030 (1) | 0.000 (1) | −0.004 (1) | 0.001 (1) |
N6 | 0.040 (2) | 0.042 (2) | 0.036 (2) | 0.010 (1) | −0.003 (1) | 0.016 (1) |
N1 | 0.019 (1) | 0.028 (1) | 0.027 (1) | −0.005 (1) | −0.002 (1) | −0.003 (1) |
C1 | 0.040 (2) | 0.053 (2) | 0.067 (3) | −0.010 (2) | 0.025 (2) | −0.007 (2) |
C2 | 0.032 (2) | 0.060 (3) | 0.087 (3) | −0.018 (2) | 0.009 (2) | 0.000 (2) |
C3 | 0.038 (2) | 0.059 (3) | 0.075 (3) | −0.022 (2) | −0.015 (2) | 0.005 (2) |
C4 | 0.061 (2) | 0.053 (2) | 0.039 (2) | −0.018 (2) | −0.006 (2) | −0.013 (2) |
C5 | 0.027 (2) | 0.034 (2) | 0.034 (2) | −0.004 (1) | 0.002 (1) | −0.001 (1) |
C6 | 0.023 (1) | 0.031 (2) | 0.033 (2) | −0.007 (1) | 0.001 (1) | 0.000 (1) |
C7 | 0.037 (1) | 0.036 (2) | 0.028 (2) | −0.018 (1) | −0.006 (1) | 0.000 (2) |
C7' | 0.0192 (4) | 0.0337 (5) | 0.0330 (5) | −0.0023 (3) | 0.0040 (3) | −0.0081 (3) |
C8 | 0.026 (2) | 0.038 (2) | 0.036 (2) | −0.010 (1) | 0.003 (1) | −0.001 (1) |
C9 | 0.025 (2) | 0.058 (2) | 0.053 (2) | −0.009 (2) | 0.012 (2) | 0.000 (2) |
C10 | 0.032 (2) | 0.053 (2) | 0.052 (2) | 0.001 (2) | 0.022 (2) | −0.005 (2) |
C11 | 0.038 (2) | 0.038 (2) | 0.046 (2) | −0.001 (2) | 0.013 (2) | −0.013 (2) |
C12 | 0.025 (1) | 0.026 (1) | 0.035 (2) | −0.002 (1) | 0.006 (1) | −0.005 (1) |
C13 | 0.021 (1) | 0.024 (1) | 0.025 (1) | −0.003 (1) | 0.000 (1) | 0.000 (1) |
C14 | 0.019 (1) | 0.024 (1) | 0.023 (1) | −0.002 (1) | 0.000 (1) | −0.002 (1) |
C15 | 0.034 (2) | 0.022 (2) | 0.039 (2) | −0.004 (1) | −0.008 (1) | 0.001 (1) |
C16 | 0.030 (2) | 0.040 (2) | 0.043 (2) | 0.001 (1) | −0.012 (1) | 0.006 (1) |
C17 | 0.027 (2) | 0.031 (2) | 0.048 (2) | −0.009 (1) | −0.012 (1) | 0.004 (1) |
C18 | 0.031 (2) | 0.038 (2) | 0.028 (2) | 0.008 (1) | 0.006 (1) | 0.005 (1) |
C19 | 0.035 (2) | 0.037 (2) | 0.040 (2) | 0.010 (1) | −0.006 (2) | 0.00491) |
C20 | 0.033 (2) | 0.042 (2) | 0.029 (2) | 0.011 (1) | 0.000 (1) | 0.002 (1) |
Geometric parameters (Å, º) top
Cu1—N1 | 2.065 (2) | C1—C2 | 1.365 (6) |
Cu1—N2i | 2.111 (2) | C2—C3 | 1.355 (6) |
Cu1—N3 | 1.967 (2) | C3—C4 | 1.410 (6) |
Cu1—N5 | 1.960 (2) | C4—C5 | 1.418 (4) |
Cu1—O4 | 2.275 (2) | C5—C6 | 1.363 (4) |
S1—O2 | 1.438 (3) | C5—C7' | 1.540 (7) |
S1—O3 | 1.432 (3) | C6—C7 | 1.515 (6) |
S1—N1 | 1.640 (2) | C8—C13 | 1.384 (4) |
S1—C5 | 1.711 (3) | C8—C9 | 1.397 (5) |
S1'—O2' | 1.433 (6) | C9—C10 | 1.361 (5) |
S1'—O3' | 1.436 (6) | C10—C11 | 1.391 (5) |
S1'—N1 | 1.631 (5) | C11—C12 | 1.374 (4) |
S1'—C6 | 1.693 (5) | C12—C13 | 1.381 (4) |
S2—O5 | 1.438 (3) | C13—C14 | 1.503 (4) |
S2—O6 | 1.440 (3) | C16—C17 | 1.336 (4) |
S2—N2 | 1.627 (2) | C19—C20 | 1.352 (4) |
S2—C12 | 1.751 (3) | N4—H4N | 0.8600 |
O1—C7 | 1.230 (6) | N6—H6N | 0.8600 |
O1'—C7' | 1.237 (7) | C1—H1 | 0.9300 |
O4—C14 | 1.223 (3) | C2—H2 | 0.9300 |
N2—C14 | 1.378 (3) | C3—H3 | 0.9300 |
N3—C15 | 1.312 (4) | C4—H4 | 0.9300 |
N3—C17 | 1.372 (4) | C8—H8 | 0.9300 |
N4—C15 | 1.327 (4) | C9—H9 | 0.9300 |
N4—C16 | 1.362 (4) | C10—H10 | 0.9300 |
N5—C18 | 1.312 (4) | C11—H11 | 0.9300 |
N5—C20 | 1.370 (4) | C15—H15 | 0.9300 |
N6—C18 | 1.336 (4) | C16—H16 | 0.9300 |
N6—C19 | 1.349 (4) | C17—H17 | 0.9300 |
N1—C7 | 1.383 (6) | C18—H18 | 0.9300 |
N1—C7' | 1.398 (8) | C19—H19 | 0.9300 |
C1—C6 | 1.354 (5) | C20—H20 | 0.9300 |
| | | |
N1—Cu1—N2i | 133.0 (1) | C1—C6—S1' | 118.1 (3) |
N1—Cu1—N3 | 93.5 (1) | C5—C6—S1' | 118.6 (3) |
N1—Cu1—N5 | 89.6 (1) | O1—C7—N1 | 121.2 (4) |
N1—Cu1—O4 | 121.4 (1) | O1—C7—C6 | 125.5 (5) |
N2—Cu1—N3i | 90.6 (1) | N1—C7—C6 | 113.2 (4) |
N2—Cu1—N5i | 92.7 (1) | O1'—C7'—N1 | 115.4 (8) |
N2i—Cu1—O4 | 105.6 (1) | O1'—C7'—C5 | 125.0 (8) |
N3—Cu1—N5 | 172.0 (1) | N1—C7'—C5 | 115.3 (5) |
N3—Cu1—O4 | 87.1 (1) | C13—C8—C9 | 116.9 (3) |
N5—Cu1—O4 | 85.0 (1) | C10—C9—C8 | 122.2 (3) |
O2—S1—O3 | 114.7 (2) | C9—C10—C11 | 121.1 (3) |
O2—S1—N1 | 112.1 (2) | C12—C11—C10 | 116.5 (3) |
O3—S1—N1 | 110.7 (2) | C11—C12—C13 | 123.1 (3) |
O2—S1—C5 | 112.0 (2) | C11—C12—S2 | 129.2 (3) |
O3—S1—C5 | 110.2 (2) | C13—C12—S2 | 107.7 (2) |
N1—S1—C5 | 95.6 (1) | C12—C13—C8 | 120.0 (3) |
O2'—S1'—O3' | 114 (1) | C12—C13—C14 | 111.6 (2) |
O2'—S1'—N1 | 118.3 (8) | C8—C13—C14 | 128.4 (3) |
O3'—S1'—N1 | 112.9 (8) | O4—C14—N2 | 123.8 (3) |
O2'—S1'—C6 | 112.1 (9) | O4—C14—C13 | 123.7 (2) |
O3'—S1'—C6 | 103.1 (8) | N2—C14—C13 | 112.4 (2) |
N1—S1'—C6 | 93.4 (3) | N3—C15—N4 | 110.7 (3) |
O5—S2—O6 | 114.9 (2) | C17—C16—N4 | 105.8 (3) |
O5—S2—N2 | 111.5 (2) | C16—C17—N3 | 109.7 (3) |
O6—S2—N2 | 110.4 (1) | N5—C18—N6 | 110.1 (3) |
O5—S2—C12 | 111.2 (2) | N6—C19—C20 | 105.7 (3) |
O6—S2—C12 | 110.2 (2) | C19—C20—N5 | 109.4 (3) |
N2—S2—C12 | 97.3 (1) | C15—N4—H4N | 125.9 |
C14—O4—Cu1 | 176.2 (2) | C16—N4—H4N | 125.9 |
C14—N2—S2 | 111.0 (2) | C18—N6—H6N | 125.6 |
C14—N2—Cu1i | 130.0 (2) | C19—N6—H6N | 125.6 |
S2—N2—Cu1i | 118.3 (1) | C6—C1—H1 | 120.8 |
C15—N3—C17 | 105.7 (3) | C2—C1—H1 | 120.8 |
C15—N3—Cu1 | 128.0 (2) | C3—C2—H2 | 119.6 |
C17—N3—Cu1 | 126.0 (2) | C1—C2—H2 | 119.6 |
C15—N4—C16 | 108.1 (3) | C2—C3—H3 | 119.1 |
C18—N5—C20 | 106.1 (3) | C4—C3—H3 | 119.1 |
C18—N5—Cu1 | 129.1 (2) | C3—C4—H4 | 121.9 |
C20—N5—Cu1 | 124.8 (2) | C5—C4—H4 | 121.9 |
C18—N6—C19 | 108.7 (3) | C13—C8—H8 | 121.5 |
C7—N1—C7' | 101.5 (5) | C9—C8—H8 | 121.5 |
C7'—N1—S1' | 110.7 (3) | C10—C9—H9 | 118.9 |
C7—N1—S1 | 110.7 (2) | C8—C9—H9 | 118.9 |
S1'—N1—S1 | 119.9 (3) | C9—C10—H10 | 119.4 |
C7—N1—Cu1 | 126.4 (2) | C11—C10—H10 | 119.4 |
C7'—N1—Cu1 | 129.9 (3) | C12—C11—H11 | 121.7 |
S1'—N1—Cu1 | 117.5 (2) | C10—C11—H11 | 121.7 |
S1—N1—Cu1 | 121.0 (1) | N3—C15—H15 | 124.7 |
C6—C1—C2 | 118.5 (4) | N4—C15—H15 | 124.7 |
C3—C2—C1 | 120.9 (4) | C17—C16—H16 | 127.1 |
C2—C3—C4 | 121.8 (4) | N4—C16—H16 | 127.1 |
C3—C4—C5 | 116.2 (3) | C16—C17—H17 | 125.1 |
C6—C5—C4 | 119.2 (3) | N3—C17—H17 | 125.1 |
C6—C5—C7' | 102.0 (4) | N5—C18—H18 | 124.9 |
C4—C5—C7' | 138.8 (4) | N6—C18—H18 | 124.9 |
C6—C5—S1 | 112.5 (2) | N6—C19—H19 | 127.2 |
C4—C5—S1 | 128.3 (3) | C20—C19—H19 | 127.2 |
C1—C6—C5 | 123.2 (3) | C19—C20—H20 | 125.3 |
C1—C6—C7 | 128.7 (4) | N5—C20—H20 | 125.3 |
C5—C6—C7 | 108.0 (3) | | |
| | | |
O5—S2—N2—C14 | 119.6 (2) | S1—C5—C6—C7 | −0.2 (2) |
O6—S2—N2—C14 | −111.4 (2) | C4—C5—C6—S1' | −178.6 (3) |
C12—S2—N2—C14 | 3.3 (2) | C7'—C5—C6—S1' | 0.0 (3) |
O5—S2—N2—Cu1i | −51.9 (2) | O2'—S1'—C6—C1 | −60.0 (9) |
O6—S2—N2—Cu1i | 77.2 (2) | O3'—S1'—C6—C1 | 63.1 (8) |
C12—S2—N2—Cu1i | −168.1 (2) | N1—S1'—C6—C1 | 177.6 (3) |
N1—Cu1—N3—C15 | −21.0 (3) | O2'—S1'—C6—C5 | 122.7 (8) |
N2i—Cu1—N3—C15 | 112.1 (3) | O3'—S1'—C6—C5 | −114.2 (8) |
O4—Cu1—N3—C15 | −142.3 (3) | N1—S1'—C6—C5 | 0.2 (3) |
N1—Cu1—N3—C17 | 165.7 (3) | S1—N1—C7—O1 | −179.6 (3) |
N2i—Cu1—N3—C17 | −61.2 (3) | Cu1—N1—C7—O1 | 16.3 (4) |
O4—Cu1—N3—C17 | 44.4 (3) | S1—N1—C7—C6 | −1.2 (3) |
N1—Cu1—N5—C18 | 109.6 (3) | Cu1—N1—C7—C6 | −165.3 (2) |
N2i—Cu1—N5—C18 | −23.4 (3) | C1—C6—C7—O1 | −4.2 (5) |
O4—Cu1—N5—C18 | −128.8 (3) | C5—C6—C7—O1 | 179.2 (3) |
N1—Cu1—N5—C20 | −68.9 (2) | C1—C6—C7—N1 | 177.5 (3) |
N2i—Cu1—N5—C20 | 158.1 (2) | C5—C6—C7—N1 | 0.9 (3) |
O4—Cu1—N5—C20 | 52.7 (2) | S1'—N1—C7'—O1' | 158 (1) |
O2'—S1'—N1—C7' | −118 (1) | Cu1—N1—C7'—O1' | −38 (1) |
O3'—S1'—N1—C7' | 105.3 (9) | S1'—N1—C7'—C5 | 0.6 (3) |
C6—S1'—N1—C7' | −0.5 (3) | Cu1—N1—C7'—C5 | 164.3 (2) |
O2'—S1'—N1—Cu1 | 76 (1) | C6—C5—C7'—O1' | −156 (2) |
O3'—S1'—N1—Cu1 | −60.7 (9) | C4—C5—C7'—O1' | 22 (2) |
C6—S1'—N1—Cu1 | −166.5 (2) | C6—C5—C7'—N1 | −0.4 (3) |
O3—S1—N1—C7 | −113.2 (2) | C4—C5—C7'—N1 | 177.8 (4) |
O2—S1—N1—C7 | 117.4 (2) | C13—C8—C9—C10 | 0.5 (6) |
C5—S1—N1—C7 | 0.9 (2) | C8—C9—C10—C11 | 1.3 (6) |
O3—S1—N1—Cu1 | 51.9 (2) | C9—C10—C11—C12 | −2.7 (6) |
O2—S1—N1—Cu1 | −77.5 (2) | C10—C11—C12—C13 | 2.3 (5) |
C5—S1—N1—Cu1 | 166.0 (2) | C10—C11—C12—S2 | −178.0 (3) |
N5—Cu1—N1—C7 | 79.3 (2) | O5—S2—C12—C11 | 61.9 (4) |
N3—Cu1—N1—C7 | −93.3 (2) | O6—S2—C12—C11 | −66.8 (4) |
N2i—Cu1—N1—C7 | 172.6 (2) | N2—S2—C12—C11 | 178.4 (3) |
O4—Cu1—N1—C7 | −4.6 (2) | O5—S2—C12—C13 | −118.4 (2) |
N5—Cu1—N1—C7' | −80.4 (3) | O6—S2—C12—C13 | 112.9 (2) |
N3—Cu1—N1—C7' | 107.0 (3) | N2—S2—C12—C13 | −2.0 (3) |
N2i—Cu1—N1—C7' | 12.9 (3) | C11—C12—C13—C8 | −0.6 (5) |
O4—Cu1—N1—C7' | −164.3 (3) | S2—C12—C13—C8 | 179.7 (2) |
N5—Cu1—N1—S1' | 82.592) | C11—C12—C13—C14 | 179.8 (3) |
N3—Cu1—N1—S1' | −90.2 (2) | S2—C12—C13—C14 | 0.1 (3) |
N2i—Cu1—N1—S1' | 175.7 (2) | C9—C8—C13—C12 | −0.8 (5) |
O4—Cu1—N1—S1' | −1.5 (2) | C9—C8—C13—C14 | 178.6 (3) |
N5—Cu1—N1—S1 | −83.391) | S2—N2—C14—O4 | 178.2 (2) |
N3—Cu1—N1—S1 | 104.1 (1) | Cu1i—N2—C14—O4 | −11.7 (4) |
N2i—Cu1—N1—S1 | 10.0 (2) | S2—N2—C14—C13 | −3.7 (3) |
O4—Cu1—N1—S1 | −167.2 (1) | Cu1i—N2—C14—C13 | 166.5 (2) |
C6—C1—C2—C3 | −3.8 (7) | C12—C13—C14—O4 | −179.6 (3) |
C1—C2—C3—C4 | 3.3 (7) | C8—C13—C14—O4 | 0.9 (5) |
C2—C3—C4—C5 | 0.8 (6) | C12—C13—C14—N2 | 2.2 (3) |
C3—C4—C5—C6 | −4.5 (5) | C8—C13—C14—N2 | −177.3 (3) |
C3—C4—C5—S1 | 177.0 (3) | C17—N3—C15—N4 | 0.4 (4) |
O3—S1—C5—C6 | 114.1 (2) | Cu1—N3—C15—N4 | −174.0 (2) |
O2—S1—C5—C6 | −116.9 (2) | C16—N4—C15—N3 | −0.2 (4) |
N1—S1—C5—C6 | −0.4 (1) | C15—N4—C16—C17 | −0.1 (4) |
O3—S1—C5—C4 | −67.4 (3) | N4—C16—C17—N3 | 0.3 (4) |
O2—S1—C5—C4 | 61.7 (3) | C15—N3—C17—C16 | −0.5 (4) |
N1—S1—C5—C4 | 178.2 (3) | Cu1—N3—C17—C16 | 174.1 (2) |
C2—C1—C6—C5 | 0.0 (5) | C20—N5—C18—N6 | −1.1 (4) |
C2—C1—C6—C7 | −176.2 (4) | Cu1—N5—C18—N6 | −179.8 (2) |
C2—C1—C6—S1' | −177.2 (4) | C19—N6—C18—N5 | 0.7 (4) |
C4—C5—C6—C1 | 4.2 (4) | C18—N6—C19—C20 | 0.0 (4) |
C7'—C5—C6—C1 | −177.1 (3) | N6—C19—C20—N5 | −0.6 (4) |
S1—C5—C6—C1 | −177.1 (3) | C18—N5—C20—C19 | 1.1 (4) |
C4—C5—C6—C7 | −178.9 (3) | Cu1—N5—C20—C19 | 179.9 (2) |
C7'—C5—C6—C7 | −0.3 (3) | | |
Symmetry code: (i) −x, −y, −z. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N4—H4N···O2ii | 0.86 | 2.45 | 2.913 (4) | 114 |
N4—H4N···O5iii | 0.86 | 2.15 | 2.966 (4) | 158 |
N6—H6N···O6iv | 0.86 | 2.43 | 2.965 (4) | 121 |
N6—H6N···O2v | 0.86 | 2.63 | 3.261 (4) | 131 |
N6—H6N···O3v | 0.86 | 2.43 | 3.036 (4) | 128 |
N6—H6N···O1′v | 0.86 | 2.27 | 2.98 (2) | 140 |
Symmetry codes: (ii) −x, −y+1, −z; (iii) x, y+1, z; (iv) x+1/2, −y−1/2, z+1/2; (v) −x+1/2, y−1/2, −z+1/2. |
Experimental details
Crystal data |
Chemical formula | [Cu2(C7H4NO3S)4(C3H4N2)4] |
Mr | 1128.10 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 298 |
a, b, c (Å) | 11.1176 (1), 11.5112 (1), 17.1203 (1) |
β (°) | 95.346 (1) |
V (Å3) | 2181.47 (3) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 1.25 |
Crystal size (mm) | 0.44 × 0.36 × 0.24 |
|
Data collection |
Diffractometer | Siemens CCD area-detector diffractometer |
Absorption correction | Empirical (using intensity measurements) (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.610, 0.754 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 15502, 5330, 4073 |
Rint | 0.068 |
(sin θ/λ)max (Å−1) | 0.667 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.051, 0.139, 0.98 |
No. of reflections | 5330 |
No. of parameters | 332 |
No. of restraints | 16 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.65, −1.24 |
Selected geometric parameters (Å, º) topCu1—N1 | 2.065 (2) | Cu1—N5 | 1.960 (2) |
Cu1—N2i | 2.111 (2) | Cu1—O4 | 2.275 (2) |
Cu1—N3 | 1.967 (2) | | |
| | | |
N1—Cu1—N2i | 133.0 (1) | N2—Cu1—N5i | 92.7 (1) |
N1—Cu1—N3 | 93.5 (1) | N2i—Cu1—O4 | 105.6 (1) |
N1—Cu1—N5 | 89.6 (1) | N3—Cu1—N5 | 172.0 (1) |
N1—Cu1—O4 | 121.4 (1) | N3—Cu1—O4 | 87.1 (1) |
N2—Cu1—N3i | 90.6 (1) | N5—Cu1—O4 | 85.0 (1) |
Symmetry code: (i) −x, −y, −z. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N4—H4N···O2ii | 0.86 | 2.45 | 2.913 (4) | 114 |
N4—H4N···O5iii | 0.86 | 2.15 | 2.966 (4) | 158 |
N6—H6N···O6iv | 0.86 | 2.43 | 2.965 (4) | 121 |
N6—H6N···O2v | 0.86 | 2.63 | 3.261 (4) | 131 |
N6—H6N···O3v | 0.86 | 2.43 | 3.036 (4) | 128 |
N6—H6N···O1'v | 0.86 | 2.27 | 2.98 (2) | 140 |
Symmetry codes: (ii) −x, −y+1, −z; (iii) x, y+1, z; (iv) x+1/2, −y−1/2, z+1/2; (v) −x+1/2, y−1/2, −z+1/2. |
Equilibrium B3LYP/6-31++G(d,p) geometry for the isolated saccharinate ion
(Å, °) topS1-O2 | 1.483 |
S1-O3 | 1.483 |
S1-N1 | 1.357 |
S1-C5 | 1.813 |
O1-C7 | 1.241 |
N1-C7 | 1.642 |
C6-C1 | 1.393 |
C1-C2 | 1.401 |
C2-C3 | 1.403 |
C3-C4 | 1.402 |
C4-C5 | 1.393 |
C5-C6 | 1.388 |
C6-C7 | 1.525 |
S1-N1-C7 | 111.9 |
S1-C5-C6 | 106.2 |
N1-S1-C5 | 96.6 |
N1-C7-C6 | 113.2 |
C1-C2-C3 | 120.7 |
C2-C3-C4 | 120.6 |
C3-C4-C5 | 117.4 |
C4-C5-C6 | 122.6 |
C5-C6-C7 | 112.1 |
C5-C6-C1 | 120.1 |
C6-C1-C2 | 118.5 |
The first-row transition metal derivatives of the artificial sweetener saccharin, 1,2-benzisothiazol-3(2H)-one 1,1-dioxide, are protease inhibitors (Supuran, 1993; Supuran et al., 1993), and superoxide dismutase-like activity has been noted for these and other metal saccharinates (Apella et al., 1993). Because imido, carbonyl and sulfonyl functionalities exist in the deprotonated saccharinate ion, the coordination chemistry of metal saccharinates is extremely rich, and the crystallographic literature presents an extraordinary variety of bonding motifs. The bonding modes can also be conveniently assigned using vibrational spectroscopy; IR measurements have also aided in unravelling the factors that govern which of the competing vicinal groups will bind to the metal atom (Jovanovski et al., 1990; Jovanovski & Šoptrajanov, 1988; Naumov & Jovanovski, 2000a,b, 2001a,b). Linking the vibrational spectral features with the X-ray results are the semi-empirical and Hartree-Fock/density functional theory (HF/DFT) ab initio force field calculations (Binev et al., 1996; Naumov & Jovanovski, 2000b,c); the calculations are particularly successful with systems such as the copper saccharinates (Naumov et al., 2001).
Our interest in the title compound, (I), arose from the disagreement in one of the two carbonyl bond distances between the X-ray structure determined by Liu et al. (1991) [R = 0.049 for 3275 reflections with I > 2σ(I)] and the structure calculated from the IR and Raman spectra (Naumov & Jovanovski, 1999a; Naumov et al., 2001). The distance in the bridging saccharinate group was normal [1.223 (5) Å], whereas that of the N-coordinated saccharinate was extremely short [1.103 (6) Å]. There were no other unusual features in the structure of (I), except for a somewhat long C—C distance and a somewhat short C—S distance in the latter group. The peculiarity was not commented on by Liu et al. (1991) in their study of (I), but the short carbonyl bond was later employed by others (Zhang et al., 1995) to explain a `space obstacle' effect arising from the neighbouring imidazole ring. The distance is short in comparison with distances found in other saccharinates [mean C—O 1.23 (2) Å; Naumov & Jovanovski, 2000a] and is even shorter than some severely electronically contracted carbonyl compounds, such as carbonyl difluoride [1.172 (1) Å] and carbonyl dichloride [1.176 (2) Å] (Kwiatkowski & Leszczynski, 1994). In fact, this bond would have a bond order (Paolini, 1990) of 2.75; however, a triple bond would not be possible, owing to the nitranionic resonance structure. The short bond contrasts with the normal distance noted in the analogous cadmium complex (Li et al., 1997). Under a more detailed analysis of the vibrational spectrum, the curve-fitted carbonyl stretching interval of the copper complex revealed a third, minor, Raman-active carbonyl component. Nevertheless, the spectrum presented convincing evidence for a normal length of 1.21–1.22 Å in all three carbonyl groups. \sch
As steric effects alone cannot account for the short bond, we carried out a re-refinement from the deposited structure factors (Supplementary Publication No. SUP 52964). However, these calculations merely confirmed the apparent correctness of the original refinements. Nonetheless, we were still doubtful of the structure, hence the present measurements. In our re-examination, the refinement on all reflections has revealed the cause of the anomaly: the isothiazolyl-3(2H)-one 1,1-dioxide portion of the monodentate saccharinate entity is disordered across a pseudo mirror plane, the ratio of the two forms being 7:1. Fig. 1 shows the structure; the minor component is now shown. One of the sulfonyl O atoms from the ordered saccharinate entity forms a strong hydrogen bond with the imidazole ring of an adjacent molecule [N···O 2.965 (4) and H···O 2.15 (6) Å, and N—H···O 171 (5)°].
The DFT calculations correctly model the isolated saccharinate ion (Fig. 2 and Table 3), whose carbonyl distance is 1.241 Å. When the anion is coordinated to a metal atom through its N atom, this bond contracts in the crystal structures (Naumov & Jovanovski, 2000a). Several restricted optimizations from modelled or previously optimized input with the anomalous parameter set to 1.103 Å, when tested on various basis sets, led either to divergence (correlated methods) or to unrealistic local minima and loss of the planarity of the o-phenylene ring (Hartree-Fock methods). The theoretical results unambiguously rule out the possibility of a stable ground-state planar saccharinate species having the short carbonyl bond length.
In contrast with the plethora of wrong spectroscopic assignments that have later been corrected by crystallographic analyses, this re-investigation represents an unusual case of a crystal structure revision that was initiated by spectroscopic assignments.