Crystal structure of dipotassium N-carbodi-thio-ato-l-prolinate trihydrate.

The mol-ecular and crystal structure of the l-proline-derived di-thio-carbamate-carboxyl-ate compound poly[tri-μ-aqua-(μ-2-carboxyl-atopyrrolidine-1-carbodi-thio-ato)dipotassium], [K2(C6H7NO2S2)(H2O)3] n or K2(SSC-NC4H7-COO)·3H2O, has been determined. The di-thio-carbamate moiety displays a unique coordination mode, comprising a 'side-on' π-coordinated K+ cation besides a commonly σ-chelated K+ cation. By bridging coordination of the CSS group, COO group and water mol-ecules, the K+ cations are linked into a two-dimensional coordination polymer extending parallel to the ab plane. These layers are again inter-connected by O-H⋯S hydrogen bonds.

Chemical context

Natural amino acids react readily with carbon di­sulfide in an alkaline environment to give di­thio­carbamate-functionalized carboxyl­ates. Since the first report on a series of barium salts in the 1950s (Zahradnik, 1956 ▸), numerous transition metal complexes have been explored. More recently, various late transition metal complexes of this family have been investigated due to their biological activity (e.g. Giovagnini et al., 2005 ▸; Cachapa et al., 2006 ▸; Nagy et al., 2012 ▸). In most cases, the di­thio­carbamate moiety acts as a classical small-bite chelate ligand, while the carboxyl­ate group (often esterified) does not contribute to metal coordination. The structural chemistry of main group derivatives of di­thio­carbamate-derived amino acids is much less explored, even though alkali metal and alkaline earth metal salts are frequently used as precursors for other metal complexes. A key inter­mediate in our ongoing reasearch on coordination polymers with di­thio­carbamate–carboxyl­ates is the l-proline-derived potassium salt K2(SSC–NC4H7–COO). This compound crystallizes from aqueous solution as a trihydrate, which has been structurally characterized in the course of this work.

Structural commentary

The title compound, K2(SSC–NC4H7–COO)·3H2O, crystallized as colourless plates in the ortho­rhom­bic space group P212121, with one formula moiety in the asymmetric unit (Fig. 1 ▸). One K atom (K2) is bonded in a typical chelating fashion by the CSS group, while K1 is coordinated ‘side-on’ to the CSS group, certainly under participation of the delocalized π electrons. This rather uncommon coordination mode might be supported by additional coordination of a carboxyl­ate O atom (O1) to K1. K1 adopts a low-symmetric seven-coordination by four carboxyl­ate O atoms, two H2O mol­ecules and the π-coordinating CSS group. K2 is eight-coordinated by three S atoms and five H2O mol­ecules (Fig. 2 ▸). Consequently, the full coordination mode of the carboxyl­ate group is μ3-κ4 O,O′:O:O′, and the di­thio­carbamate group adopts a μ3-κ6 S,S′,C:S,S′:S coordination. One H2O mol­ecule displays a μ3-coordination (O3) and the remaining two H2O mol­ecules are coordinating in a μ-bridging mode (O4 and O5). The K—S distances at the σ-chelated K+ cation (K2) are 3.2176 (8) and 3.2650 (9) Å, while the K—S separations at the π-coordinated K+ cation (K1) are significantly longer at 3.2956 (9) and 3.4463 (8) Å. The coordination mode of the di­thio­carbamate group in the title compound [see (C) in Fig. 3 ▸] is unique, to our knowledge. The most frequently observed coordination pattern in di­thio­carbamates of the heavier alkali metals (K, Rb and Cs) is a symmetric double-chelating mode, leading to a puckered S2 M 2 ring (e.g. Howie et al., 2008 ▸; Reyes-Martínez et al., 2009 ▸; Mafud, 2012 ▸; see (B) in Fig. 3 ▸]. Nonetheless, the values of the K—S separations in the title compound cover the same range as observed in the reference compounds. A simple chelating coordination with significantly shorter K—S contacts is realized when the K+ cation is coordinatively highly saturated, as has been observed in a crown ether complex [Arman et al., 2013 ▸; see (A) in Fig. 3 ▸]. In the title compound, three of the four K—O(carboxyl­ate) contacts are in a range 2.676 (2)–2.802 (2) Å, which is consistent with the values observed in other potassium carboxyl­ates (e.g. Ilczyszyn et al., 2009 ▸; Liebing et al., 2016 ▸). However, one contact (K1′—O1) is strongly elongated to 3.358 (2) Å. The K—O(H2O) bond lengths cover a range of 2.723 (2)–3.065 (3) Å.

Figure 1

The asymmetric unit of the title compound. Displacement ellipsoids for non-H atoms are drawn at the 50% probability level and H atoms attached to C atoms have been omitted for clarity. Adjacent symmetry-related K+ cations are illustrated as semi-transparent spheres.

Figure 2

Illustration of the coordination environment of the two K+ cations.

Figure 3

The different coordination modes of the di­thio­carbamate group in potassium complexes: single-chelating (A), symmetric double-chelating (B) and single-chelating combined with π-coordination (this work; C).

Supra­molecular features

As a result of the bridging coordination of the carboxyl­ate group, the di­thio­carbamate group and the water mol­ecules, a two-dimensional polymeric structure parallel to the ab plane is built (Figs. 4 ▸ and 5 ▸). This arrangement is likely supported by O3—H⋯O1i, O3—H⋯S2ii, O4—H⋯O2iii and O5—H⋯O1 hydrogen bonds within the layer (Table 1 ▸). The layer surfaces are defined by the hydro­phobic hydro­carbon backbones, but additionally the two-dimensional arrays are apparently inter­connected by O5—H⋯S1iv hydrogen bonds.

Figure 4

Supramolecular crystal structure comprising polymeric layers extending parallel to (001), viewed in a projection on (100). The bold black lines mark the unit-cell dimensions.

Figure 5

The supra­molecular layer illustrated in Fig. 4 ▸, viewed in a projection on (010).

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H9⋯O1i	0.83 (2)	1.93 (2)	2.752 (3)	170 (4)
O3—H8⋯S2ii	0.81 (2)	2.57 (2)	3.3123 (19)	153 (3)
O4—H11⋯O2iii	0.80 (2)	2.22 (2)	3.000 (3)	166 (4)
O5—H13⋯O1	0.81 (2)	1.99 (3)	2.724 (3)	150 (3)
O5—H12⋯S1iv	0.81 (2)	2.55 (2)	3.341 (2)	163 (3)

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) .

Database survey

For other potassium di­thio­carbamates, see e.g. Cambridge Structural Database (CSD; Groom et al., 2016 ▸) refcode AGEHIF (Arman et al., 2013 ▸), KOLLIH (Howie et al., 2008 ▸), LEHRUN (Mafud, 2012 ▸).

For other potassium carboxyl­ates, see e.g. CONWOS (Ilczyszyn et al., 2009 ▸), and BIFMIN01 and BIFMUZ01 (Liebing et al., 2016 ▸).

Synthesis and crystallization

A slight excess of carbon di­sulfide (approximately 4 ml, 0.06 mol) was added to a solution of l-proline (5.76 g, 0.05 mol) and potassium hydroxide (5.61 g, 0.10 mol) in 30 ml water and the resulting solution was stirred vigorously overnight. The yellow solution obtained was filtered and reduced to dryness in vacuo. The crystalline residue was washed with several portions of tetra­hydro­furan and diethyl ether, and dried in vacuo, providing analytically pure K2(SSC–NC4H7–COO)·3H2O in almost qu­anti­tative (>95%) yield as colourless to light-brown low-melting plates, which are very soluble in water. Single crystals suitable for X-ray structure analysis were obtained by slow evaporation of a concentrated aqueous solution at room temperature. IR: 3372 (s br), 3226 (sh br), 2985 (m), 2949 (m), 2875 (w), 1641 (sh), 1603 (sh), 1587 (s), 1497 (s), 1443 (s), 1374 (s), 1338 (m), 1316 (w), 1290 (s), 1257 (m), 1230 (w), 1176 (m), 1155 (s), 1083 (w), 1050 (w), 1003 (m), 948 (m), 918 (m), 899 (w), 846 (m), 794 (m), 666 (s br), 562 (s), 479 (s), 446 (m) cm−1. 1H NMR [400 MHz, D2O, 298 (2) K]: δ 1.89–1.98 (3 × m, 3H; 3-CH 2 + 4-CH 2), 2.24 (m, 1H; 3-CH 2), 3.75 (m, 1H; 5-CH 2), 3.83 (m, 1H; 5-CH 2), 4.72 (dd, J 1 = 8.7, J 2 = 3.2 Hz, 1H; 2-CH). 13C NMR [100 MHz, D2O, 298 (2) K]: δ 24.6 (4-CH2), 31.5 (3-CH2), 55.7 (5-CH2), 69.5 (2-CH), 179.9 (COO), 205.8 (CSS).

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2 ▸. H atoms on C atoms were fixed geometrically and refined using a riding model, with U iso(H) = 1.2U eq(C). C—H distances within the CH2 groups were constrained to 0.99 Å and that within the CH group to 1.00 Å. The water H-atom sites were located in difference Fourier maps and refined using restraints on the O—H distance [target value = 0.84 (2) Å]. The corresponding U iso(H) values were set at 1.5U eq(O). The reflection (002) disagreed strongly with the structural model and was therefore omitted from the refinement.

Table 2

Experimental details

Crystal data
Chemical formula	[K2(C6H7NO2S2)(H2O)3]
M r	321.49
Crystal system, space group	Orthorhombic, P212121
Temperature (K)	153
a, b, c (Å)	7.1700 (3), 8.9723 (4), 19.8379 (7)
V (Å3)	1276.20 (9)
Z	4
Radiation type	Mo Kα
μ (mm−1)	1.07
Crystal size (mm)	0.44 × 0.10 × 0.07
Data collection
Diffractometer	Stoe IPDS 2T
Absorption correction	Numerical (X-AREA and X-RED; Stoe & Cie, 2002 ▸)
T min, T max	0.741, 0.935
No. of measured, independent and observed [I > 2σ(I)] reflections	8831, 2794, 2511
R int	0.038
(sin θ/λ)max (Å−1)	0.639
Refinement
R[F 2 > 2σ(F 2)], wR(F 2), S	0.023, 0.042, 0.97
No. of reflections	2794
No. of parameters	164
No. of restraints	6
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)	0.25, −0.22
Absolute structure	Flack x determined using 979 quotients [(I +) − (I −)]/[(I +) + (I −)] (Parsons et al., 2013 ▸)
Absolute structure parameter	0.00 (4)

Computer programs: X-AREA (Stoe & Cie, 2002 ▸), X-RED (Stoe & Cie, 2002 ▸), SIR97 (Altomare et al., 1999 ▸), SHELXL2016 (Sheldrick, 2015 ▸), DIAMOND (Brandenburg, 1999 ▸) and publCIF (Westrip, 2010 ▸).

Crystal structure: contains datablock(s) I. DOI: 10.1107/S2056989017011999/zl2712sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989017011999/zl2712Isup2.hkl

CCDC reference: 1569563

Additional supporting information: crystallographic information; 3D view; checkCIF report

[K2(C6H7NO2S2)(H2O)3]	Dx = 1.673 Mg m−3
Mr = 321.49	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, P212121	Cell parameters from 10736 reflections
a = 7.1700 (3) Å	θ = 2.5–29.2°
b = 8.9723 (4) Å	µ = 1.07 mm−1
c = 19.8379 (7) Å	T = 153 K
V = 1276.20 (9) Å3	Plate, colorless
Z = 4	0.44 × 0.10 × 0.07 mm
F(000) = 664

Stoe IPDS 2T diffractometer	2794 independent reflections
Radiation source: fine-focus sealed tube	2511 reflections with I > 2σ(I)
Detector resolution: 6.67 pixels mm-1	Rint = 0.038
ω scan	θmax = 27.0°, θmin = 2.5°
Absorption correction: numerical (X-AREA and X-RED; Stoe & Cie, 2002)	h = −9→9
Tmin = 0.741, Tmax = 0.935	k = −11→11
8831 measured reflections	l = −22→25

Refinement on F2	Hydrogen site location: mixed
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.023	w = 1/[σ2(Fo2) + (0.0175P)2] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.042	(Δ/σ)max = 0.001
S = 0.97	Δρmax = 0.25 e Å−3
2794 reflections	Δρmin = −0.22 e Å−3
164 parameters	Extinction correction: SHELXL2016 (Sheldrick, 2015), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
6 restraints	Extinction coefficient: 0.0051 (7)
Primary atom site location: heavy-atom method	Absolute structure: Flack x determined using 979 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
Secondary atom site location: difference Fourier map	Absolute structure parameter: 0.00 (4)

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.

	x	y	z	Uiso*/Ueq
C1	0.0231 (3)	0.2133 (3)	0.89993 (13)	0.0120 (5)
C2	−0.0116 (3)	0.3153 (3)	0.83918 (13)	0.0103 (5)
H1	−0.098814	0.397715	0.851816	0.012*
C3	0.2180 (4)	0.3035 (3)	0.74906 (14)	0.0140 (6)
H3	0.348536	0.268134	0.751636	0.017*
H2	0.205712	0.372618	0.710395	0.017*
C4	0.0837 (4)	0.1734 (3)	0.74238 (15)	0.0157 (6)
H5	0.135307	0.082539	0.763649	0.019*
H4	0.056006	0.152175	0.694439	0.019*
C5	−0.0907 (4)	0.2267 (3)	0.77943 (14)	0.0156 (6)
H6	−0.166526	0.141324	0.795180	0.019*
H7	−0.168314	0.290872	0.750111	0.019*
C6	0.2657 (3)	0.4759 (3)	0.84517 (12)	0.0098 (5)
N	0.1619 (3)	0.3766 (2)	0.81226 (11)	0.0092 (4)
O1	0.1821 (2)	0.1556 (2)	0.90730 (10)	0.0157 (4)
O2	−0.1122 (2)	0.1894 (2)	0.93751 (12)	0.0207 (4)
O3	0.7663 (3)	0.5383 (3)	0.98964 (10)	0.0217 (4)
H8	0.856 (4)	0.512 (4)	0.9680 (15)	0.033*
H9	0.747 (4)	0.471 (4)	1.0179 (15)	0.033*
O4	0.9025 (3)	0.8561 (2)	0.92654 (13)	0.0280 (5)
H10	0.999 (4)	0.821 (4)	0.912 (2)	0.042*
H11	0.914 (5)	0.943 (3)	0.934 (2)	0.042*
O5	0.4779 (3)	0.0059 (2)	0.85399 (10)	0.0240 (5)
H13	0.373 (3)	0.038 (4)	0.8575 (18)	0.036*
H12	0.505 (4)	−0.005 (4)	0.8144 (12)	0.036*
K1	0.53230 (8)	0.28003 (6)	0.93500 (3)	0.01712 (14)
K2	0.54335 (7)	0.76029 (6)	0.93744 (3)	0.01595 (13)
S1	0.47870 (8)	0.52667 (8)	0.81344 (3)	0.01487 (14)
S2	0.18705 (8)	0.54540 (7)	0.92079 (3)	0.01487 (15)

	U11	U22	U33	U12	U13	U23
C1	0.0121 (11)	0.0107 (12)	0.0133 (13)	−0.0024 (9)	−0.0008 (10)	−0.0016 (9)
C2	0.0068 (11)	0.0108 (11)	0.0134 (13)	0.0003 (9)	−0.0006 (10)	0.0007 (9)
C3	0.0154 (14)	0.0153 (13)	0.0112 (14)	−0.0017 (10)	0.0030 (10)	−0.0030 (11)
C4	0.0192 (14)	0.0133 (13)	0.0145 (15)	−0.0047 (10)	−0.0023 (10)	−0.0031 (11)
C5	0.0151 (12)	0.0151 (14)	0.0167 (15)	−0.0028 (10)	−0.0038 (10)	−0.0007 (11)
C6	0.0097 (10)	0.0096 (11)	0.0100 (12)	0.0016 (10)	−0.0005 (8)	0.0021 (11)
N	0.0095 (9)	0.0086 (10)	0.0096 (11)	−0.0024 (8)	−0.0003 (8)	−0.0004 (8)
O1	0.0135 (8)	0.0164 (9)	0.0171 (11)	0.0057 (8)	0.0000 (8)	0.0034 (8)
O2	0.0127 (8)	0.0312 (12)	0.0183 (11)	−0.0002 (7)	0.0040 (9)	0.0082 (10)
O3	0.0206 (9)	0.0208 (10)	0.0237 (11)	0.0048 (8)	0.0084 (8)	0.0098 (10)
O4	0.0223 (10)	0.0214 (11)	0.0403 (16)	−0.0048 (8)	0.0009 (10)	−0.0010 (12)
O5	0.0233 (9)	0.0330 (13)	0.0158 (10)	0.0126 (9)	0.0033 (8)	0.0009 (9)
K1	0.0115 (2)	0.0201 (3)	0.0197 (3)	0.0003 (2)	−0.0003 (3)	0.0014 (2)
K2	0.0146 (3)	0.0140 (3)	0.0192 (3)	−0.0005 (2)	−0.0023 (3)	−0.0006 (2)
S1	0.0125 (3)	0.0187 (3)	0.0134 (3)	−0.0058 (3)	0.0023 (2)	−0.0005 (3)
S2	0.0135 (3)	0.0182 (3)	0.0129 (3)	−0.0022 (3)	0.0020 (2)	−0.0062 (3)

C1—O2	1.242 (3)	O3—K1	3.060 (2)
C1—O1	1.261 (3)	O3—H8	0.81 (2)
C1—C2	1.533 (4)	O3—H9	0.83 (2)
C1—K1i	3.276 (3)	O4—K2	2.723 (2)
C2—N	1.462 (3)	O4—K2iii	3.065 (3)
C2—C5	1.536 (4)	O4—H10	0.81 (2)
C2—H1	1.0000	O4—H11	0.80 (2)
C3—N	1.471 (3)	O5—K2iv	2.796 (2)
C3—C4	1.519 (4)	O5—K1	2.964 (2)
C3—H3	0.9900	O5—H13	0.81 (2)
C3—H2	0.9900	O5—H12	0.81 (2)
C4—C5	1.527 (4)	K1—O2v	2.6758 (19)
C4—H5	0.9900	K1—O2vi	2.747 (2)
C4—H4	0.9900	K1—C1vi	3.276 (3)
C5—H6	0.9900	K1—S1	3.2956 (9)
C5—H7	0.9900	K1—O1vi	3.358 (2)
C6—N	1.332 (3)	K1—S2	3.4463 (8)
C6—S1	1.714 (2)	K1—H9	2.83 (4)
C6—S2	1.719 (3)	K1—H13	2.90 (4)
C6—K1	3.150 (2)	K2—O5vii	2.796 (2)
O1—K1	2.8023 (19)	K2—O3viii	3.050 (2)
O1—K1i	3.358 (2)	K2—O4viii	3.065 (3)
O2—K1ii	2.6758 (19)	K2—S2	3.2176 (8)
O2—K1i	2.747 (2)	K2—S1	3.2650 (9)
O3—K2	2.756 (2)	K2—S2iii	3.4656 (9)
O3—K2iii	3.050 (2)	S2—K2viii	3.4656 (9)
O2—C1—O1	124.5 (2)	C6—K1—K2	57.29 (5)
O2—C1—C2	116.6 (2)	C1vi—K1—K2	88.33 (4)
O1—C1—C2	118.9 (2)	S1—K1—K2	48.625 (16)
O2—C1—K1i	54.47 (14)	O1vi—K1—K2	79.14 (4)
O1—C1—K1i	82.72 (15)	S2—K1—K2	47.420 (14)
C2—C1—K1i	141.07 (16)	O2v—K1—K1vi	35.39 (5)
N—C2—C1	111.93 (19)	O2vi—K1—K1vi	77.43 (4)
N—C2—C5	103.1 (2)	O1—K1—K1vi	141.94 (4)
C1—C2—C5	110.9 (2)	O5—K1—K1vi	108.66 (4)
N—C2—H1	110.2	O3—K1—K1vi	56.26 (4)
C1—C2—H1	110.2	C6—K1—K1vi	152.21 (5)
C5—C2—H1	110.2	C1vi—K1—K1vi	55.88 (5)
N—C3—C4	104.1 (2)	S1—K1—K1vi	126.83 (2)
N—C3—H3	110.9	O1vi—K1—K1vi	39.01 (3)
C4—C3—H3	110.9	S2—K1—K1vi	135.23 (3)
N—C3—H2	110.9	K2—K1—K1vi	95.725 (18)
C4—C3—H2	110.9	O2v—K1—H9	69.9 (7)
H3—C3—H2	109.0	O2vi—K1—H9	67.0 (6)
C3—C4—C5	103.7 (2)	O1—K1—H9	147.4 (6)
C3—C4—H5	111.0	O5—K1—H9	152.8 (7)
C5—C4—H5	111.0	O3—K1—H9	15.6 (5)
C3—C4—H4	111.0	C6—K1—H9	108.6 (6)
C5—C4—H4	111.0	C1vi—K1—H9	54.5 (5)
H5—C4—H4	109.0	S1—K1—H9	94.6 (5)
C4—C5—C2	103.4 (2)	O1vi—K1—H9	35.0 (5)
C4—C5—H6	111.1	S2—K1—H9	91.1 (6)
C2—C5—H6	111.1	K2—K1—H9	51.5 (6)
C4—C5—H7	111.1	K1vi—K1—H9	45.5 (6)
C2—C5—H7	111.1	O2v—K1—H13	99.1 (5)
H6—C5—H7	109.0	O2vi—K1—H13	114.5 (7)
N—C6—S1	119.70 (18)	O1—K1—H13	40.8 (5)
N—C6—S2	119.16 (17)	O5—K1—H13	15.8 (4)
S1—C6—S2	121.09 (15)	O3—K1—H13	166.5 (6)
N—C6—K1	104.05 (16)	C6—K1—H13	83.0 (6)
S1—C6—K1	79.34 (8)	C1vi—K1—H13	122.4 (7)
S2—C6—K1	84.71 (9)	S1—K1—H13	94.0 (7)
C6—N—C2	123.2 (2)	O1vi—K1—H13	138.6 (7)
C6—N—C3	124.3 (2)	S2—K1—H13	101.0 (5)
C2—N—C3	112.12 (18)	K2—K1—H13	139.7 (7)
C1—O1—K1	132.01 (16)	K1vi—K1—H13	122.3 (6)
C1—O1—K1i	75.41 (15)	H9—K1—H13	167.8 (8)
K1—O1—K1i	92.03 (5)	O4—K2—O3	73.12 (7)
C1—O2—K1ii	132.87 (17)	O4—K2—O5vii	82.11 (7)
C1—O2—K1i	103.94 (16)	O3—K2—O5vii	152.81 (6)
K1ii—O2—K1i	110.25 (8)	O4—K2—O3viii	117.80 (6)
K2—O3—K2iii	97.35 (7)	O3—K2—O3viii	128.88 (4)
K2—O3—K1	95.52 (6)	O5vii—K2—O3viii	72.82 (6)
K2iii—O3—K1	166.87 (8)	O4—K2—O4viii	119.29 (6)
K2—O3—H8	118 (2)	O3—K2—O4viii	67.29 (6)
K2iii—O3—H8	85 (3)	O5vii—K2—O4viii	137.28 (6)
K1—O3—H8	92 (3)	O3viii—K2—O4viii	64.51 (6)
K2—O3—H9	133 (2)	O4—K2—S2	158.71 (6)
K2iii—O3—H9	103 (2)	O3—K2—S2	93.79 (5)
K1—O3—H9	66 (2)	O5vii—K2—S2	106.15 (5)
H8—O3—H9	106 (3)	O3viii—K2—S2	83.48 (4)
K2—O4—K2iii	97.70 (8)	O4viii—K2—S2	67.94 (5)
K2—O4—H10	135 (3)	O4—K2—S1	106.09 (6)
K2iii—O4—H10	84 (3)	O3—K2—S1	84.35 (5)
K2—O4—H11	113 (2)	O5vii—K2—S1	92.06 (5)
K2iii—O4—H11	98 (3)	O3viii—K2—S1	130.18 (4)
H10—O4—H11	111 (4)	O4viii—K2—S1	113.44 (5)
K2iv—O5—K1	108.11 (6)	S2—K2—S1	54.915 (17)
K2iv—O5—H13	113 (3)	O4—K2—S2iii	67.95 (6)
K1—O5—H13	77 (3)	O3—K2—S2iii	83.46 (5)
K2iv—O5—H12	116 (3)	O5vii—K2—S2iii	97.70 (5)
K1—O5—H12	126 (3)	O3viii—K2—S2iii	60.71 (4)
H13—O5—H12	110 (3)	O4viii—K2—S2iii	63.57 (5)
O2v—K1—O2vi	111.87 (5)	S2—K2—S2iii	128.38 (2)
O2v—K1—O1	137.40 (6)	S1—K2—S2iii	167.58 (2)
O2vi—K1—O1	83.24 (6)	O4—K2—K1	109.40 (5)
O2v—K1—O5	83.31 (6)	O3—K2—K1	44.96 (5)
O2vi—K1—O5	122.17 (6)	O5vii—K2—K1	141.10 (5)
O1—K1—O5	56.29 (5)	O3viii—K2—K1	125.84 (4)
O2v—K1—O3	72.61 (6)	O4viii—K2—K1	70.31 (4)
O2vi—K1—O3	78.76 (6)	S2—K2—K1	52.061 (16)
O1—K1—O3	149.61 (6)	S1—K2—K1	49.238 (17)
O5—K1—O3	153.24 (6)	S2iii—K2—K1	121.17 (2)
O2v—K1—C6	139.31 (7)	O4—K2—K2iii	44.10 (5)
O2vi—K1—C6	103.67 (6)	O3—K2—K2iii	43.88 (5)
O1—K1—C6	64.38 (6)	O5vii—K2—K2iii	120.53 (5)
O5—K1—C6	94.38 (6)	O3viii—K2—K2iii	106.88 (4)
O3—K1—C6	96.35 (6)	O4viii—K2—K2iii	75.86 (5)
O2v—K1—C1vi	90.35 (7)	S2—K2—K2iii	133.26 (3)
O2vi—K1—C1vi	21.59 (6)	S1—K2—K2iii	121.19 (2)
O1—K1—C1vi	100.67 (6)	S2iii—K2—K2iii	46.809 (17)
O5—K1—C1vi	123.68 (6)	K1—K2—K2iii	88.808 (18)
O3—K1—C1vi	69.09 (6)	O4—K2—K2viii	146.64 (6)
C6—K1—C1vi	122.90 (6)	O3—K2—K2viii	103.43 (5)
O2v—K1—S1	109.19 (5)	O5vii—K2—K2viii	103.43 (4)
O2vi—K1—S1	124.25 (4)	O3viii—K2—K2viii	38.77 (4)
O1—K1—S1	91.12 (4)	O4viii—K2—K2viii	38.20 (4)
O5—K1—S1	98.34 (4)	S2—K2—K2viii	51.744 (13)
O3—K1—S1	79.31 (4)	S1—K2—K2viii	106.540 (19)
C6—K1—S1	30.73 (4)	S2iii—K2—K2viii	78.70 (2)
C1vi—K1—S1	135.80 (5)	K1—K2—K2viii	87.075 (19)
O2v—K1—O1vi	74.35 (6)	K2iii—K2—K2viii	110.46 (3)
O2vi—K1—O1vi	41.03 (5)	O4—K2—K1vii	72.51 (5)
O1—K1—O1vi	122.54 (5)	O3—K2—K1vii	137.42 (5)
O5—K1—O1vi	133.64 (5)	O5vii—K2—K1vii	37.15 (4)
O3—K1—O1vi	50.52 (5)	O3viii—K2—K1vii	53.25 (4)
C6—K1—O1vi	128.70 (6)	O4viii—K2—K1vii	110.14 (5)
C1vi—K1—O1vi	21.87 (5)	S2—K2—K1vii	125.77 (2)
S1—K1—O1vi	127.12 (4)	S1—K2—K1vii	129.17 (2)
O2v—K1—S2	153.59 (5)	S2iii—K2—K1vii	60.694 (17)
O2vi—K1—S2	74.66 (4)	K1—K2—K1vii	177.62 (2)
O1—K1—S2	67.40 (4)	K2iii—K2—K1vii	93.565 (18)
O5—K1—S2	115.75 (4)	K2viii—K2—K1vii	91.962 (18)
O3—K1—S2	84.23 (4)	C6—S1—K2	91.16 (9)
C6—K1—S2	29.79 (5)	C6—S1—K1	69.92 (8)
C1vi—K1—S2	93.14 (5)	K2—S1—K1	82.14 (2)
S1—K1—S2	52.585 (17)	C6—S2—K2	92.67 (8)
O1vi—K1—S2	100.79 (4)	C6—S2—K1	65.51 (8)
O2v—K1—K2	106.61 (4)	K2—S2—K1	80.519 (19)
O2vi—K1—K2	84.08 (4)	C6—S2—K2viii	171.04 (10)
O1—K1—K2	114.65 (4)	K2—S2—K2viii	81.447 (18)
O5—K1—K2	146.95 (4)	K1—S2—K2viii	119.65 (2)
O3—K1—K2	39.52 (4)
O2—C1—C2—N	160.5 (2)	C4—C3—N—C2	−8.5 (3)
O1—C1—C2—N	−21.9 (3)	O2—C1—O1—K1	−116.4 (2)
K1i—C1—C2—N	95.0 (3)	C2—C1—O1—K1	66.3 (3)
O2—C1—C2—C5	−84.9 (3)	K1i—C1—O1—K1	−79.32 (18)
O1—C1—C2—C5	92.6 (3)	O2—C1—O1—K1i	−37.0 (2)
K1i—C1—C2—C5	−150.4 (2)	C2—C1—O1—K1i	145.6 (2)
N—C3—C4—C5	28.1 (3)	O1—C1—O2—K1ii	−176.93 (17)
C3—C4—C5—C2	−37.1 (3)	C2—C1—O2—K1ii	0.5 (3)
N—C2—C5—C4	31.5 (3)	K1i—C1—O2—K1ii	135.8 (2)
C1—C2—C5—C4	−88.5 (3)	O1—C1—O2—K1i	47.3 (3)
S1—C6—N—C2	173.28 (17)	C2—C1—O2—K1i	−135.35 (18)
S2—C6—N—C2	−4.1 (3)	N—C6—S1—K2	178.61 (19)
K1—C6—N—C2	87.7 (2)	S2—C6—S1—K2	−4.09 (15)
S1—C6—N—C3	0.5 (3)	K1—C6—S1—K2	−81.19 (4)
S2—C6—N—C3	−176.82 (19)	N—C6—S1—K1	−100.2 (2)
K1—C6—N—C3	−85.1 (2)	S2—C6—S1—K1	77.11 (14)
C1—C2—N—C6	−68.8 (3)	N—C6—S2—K2	−178.53 (19)
C5—C2—N—C6	171.9 (2)	S1—C6—S2—K2	4.15 (15)
C1—C2—N—C3	104.8 (2)	K1—C6—S2—K2	78.32 (4)
C5—C2—N—C3	−14.5 (3)	N—C6—S2—K1	103.2 (2)
C4—C3—N—C6	165.0 (2)	S1—C6—S2—K1	−74.17 (14)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H9···O1vi	0.83 (2)	1.93 (2)	2.752 (3)	170 (4)
O3—H8···S2v	0.81 (2)	2.57 (2)	3.3123 (19)	153 (3)
O4—H11···O2ix	0.80 (2)	2.22 (2)	3.000 (3)	166 (4)
O5—H13···O1	0.81 (2)	1.99 (3)	2.724 (3)	150 (3)
O5—H12···S1x	0.81 (2)	2.55 (2)	3.341 (2)	163 (3)