catena-Poly[[(18-crown-6)potassium(I)]-μ-chlorido-silver(I)-μ-chlorido]

The title complex, [AgKCl₂(C₁₂H₂₄O₆)]_n, has been synthesized by reaction of 18-crown-6 with KCl and AgNO₃. [K(18-crown-6)]⁺ cations and [AgCl₂]⁻ anions form one-dimensional chains through K...Cl inter­actions of length 3.2568 (14) Å. Both the K⁺ and the Ag^I ions lie on centres of inversion.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.027
• wR factor = 0.079
• Data-to-parameter ratio = 16.5

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for        Cl1
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         K1

Alert level G
PLAT794_ALERT_5_G Check Predicted Bond Valency for Ag1         (1)       1.10

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

Much interest has been focused on crown ethers and their metal cations because they can act as modules to form novel polymeric structures (Desai et al., 2001; Bastos et al., 2000). The title complex consists of [K(18-crown-6)]⁺ cations linked by [AgCl₂]^- anions (Figure 1).

The Ag^I atom lies on a centre of inversion and is coordinated in a linear manner by by two Cl atoms with an Ag—Cl bond length of 2.3114 (10) Å. In the [K(18-crown-6)]⁺ cation, K⁺ lies on a centre of inversion and is coordinated by six O atoms, with K⁺ lying approximately in the plane of the crown ether. The K—O bond lengths vary from 2.783 (2) to 2.830 (2) Å. The cations and anions are linked via K—Cl interactions of length 3.2568 (14) Å, forming one-dimensional chains along the b axis (Figure 2).

Related literature

For other examples of structures incorporating [AgCl₂]^- anions, see: Exarchos et al. (1998); Gerisch et al. (1997). For polymeric structures incorporating crown ethers, see: Desai et al. (2001); Bastos et al. (2000).

S2. Experimental

KCl (0.2238 g, 3.0 mmol) and AgNO₃ (0.2548 g,1.5 mmol) in 15 ml e thanol were refluxed for 4 h, then 18-crown-6 (0.421 g, 1.5 mmol) was added slowly and the mixture was refluxed for a further 4 h. After cooling to room temperature, the mixture was filtered and the resulting solid was recrystallized from ether. Elemental analysis: calculated C 29.89, H 4.98%; found: C 30.02, H 4.99.

S3. Refinement

H atoms were positioned geometrically and refined using a riding model with C—H = 0.97 Å and U_iso(H) = 1.2U_eq(C).

Computing details

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: SHELXTL (Bruker, 1997); software used to prepare material for publication: SHELXTL.

Figures

	Fig. 1. Molecular structure of the title compound showing displacement ellipsoids at the 30% probability level. H atoms are omitted. Symmetry code (A): 1 - x, 1 - y, 1 - z.
	Fig. 2. One-dimensional chain running along the b-axis.

catena-Poly[[(18-crown-6)potassium(I)]-µ-chlorido-silver(I)-µ-chlorido]

Crystal data

[AgKCl2(C12H24O6)]	F(000) = 488
Mr = 482.18	Dx = 1.657 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2464 reflections
a = 8.691 (4) Å	θ = 2.9–26.1°
b = 8.244 (4) Å	µ = 1.56 mm^−1
c = 13.833 (6) Å	T = 298 K
β = 102.764 (6)°	Block, colourless
V = 966.6 (8) Å^3	0.56 × 0.34 × 0.30 mm
Z = 2

Data collection

Bruker SMART CCD diffractometer	1699 independent reflections
Radiation source: fine-focus sealed tube	1308 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.020
φ and ω scans	θmax = 25.0°, θmin = 2.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −6→10
Tmin = 0.457, Tmax = 0.627	k = −9→9
4877 measured reflections	l = −15→16

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.027	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.079	H-atom parameters constrained
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0449P)^2 + 0.1659P] where P = (Fo^2 + 2Fc^2)/3
1699 reflections	(Δ/σ)max < 0.001
103 parameters	Δρmax = 0.20 e Å^−3
0 restraints	Δρmin = −0.37 e Å^−3

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 F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	Uiso*/Ueq
Cl1	0.68538 (10)	0.17256 (10)	0.45904 (7)	0.0811 (3)
Ag1	0.5000	0.0000	0.5000	0.06429 (16)
K1	0.5000	0.5000	0.5000	0.0469 (2)
O1	0.5045 (3)	0.5512 (2)	0.29837 (13)	0.0602 (5)
O2	0.7752 (2)	0.6133 (2)	0.45167 (15)	0.0629 (5)
O3	0.7445 (2)	0.6290 (2)	0.64818 (13)	0.0624 (5)
C1	0.4100 (4)	0.4327 (4)	0.2368 (2)	0.0764 (10)
H1A	0.4570	0.3261	0.2510	0.092*
H1B	0.4053	0.4573	0.1677	0.092*
C2	0.6609 (4)	0.5529 (4)	0.2855 (2)	0.0704 (9)
H2A	0.6617	0.5810	0.2176	0.084*
H2B	0.7074	0.4461	0.2992	0.084*
C3	0.7541 (4)	0.6736 (4)	0.3540 (2)	0.0722 (9)
H3A	0.8557	0.6905	0.3375	0.087*
H3B	0.6988	0.7765	0.3483	0.087*
C4	0.8766 (4)	0.7074 (4)	0.5233 (3)	0.0775 (10)
H4A	0.8337	0.8158	0.5251	0.093*
H4B	0.9792	0.7162	0.5070	0.093*
C5	0.8922 (3)	0.6288 (4)	0.6205 (3)	0.0782 (10)
H5A	0.9286	0.5181	0.6172	0.094*
H5B	0.9695	0.6865	0.6698	0.094*
C6	0.7508 (4)	0.5672 (5)	0.7444 (2)	0.0775 (10)
H6A	0.8198	0.6339	0.7932	0.093*
H6B	0.7925	0.4576	0.7495	0.093*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0670 (5)	0.0692 (5)	0.1129 (7)	0.0011 (4)	0.0325 (5)	0.0147 (4)
Ag1	0.0596 (2)	0.0636 (2)	0.0702 (2)	−0.00286 (15)	0.01553 (17)	0.00199 (15)
K1	0.0389 (4)	0.0580 (5)	0.0438 (4)	−0.0085 (3)	0.0093 (3)	−0.0009 (3)
O1	0.0699 (13)	0.0619 (11)	0.0505 (11)	0.0093 (10)	0.0171 (10)	0.0017 (9)
O2	0.0523 (11)	0.0603 (12)	0.0785 (13)	−0.0153 (10)	0.0193 (10)	0.0032 (10)
O3	0.0484 (11)	0.0703 (12)	0.0614 (12)	0.0053 (9)	−0.0029 (9)	−0.0083 (9)
C1	0.110 (3)	0.0723 (19)	0.0434 (16)	0.006 (2)	0.0098 (18)	−0.0033 (15)
C2	0.089 (2)	0.0700 (18)	0.0629 (19)	0.0200 (19)	0.0393 (18)	0.0167 (16)
C3	0.0593 (18)	0.0677 (19)	0.102 (3)	0.0081 (16)	0.0450 (19)	0.0265 (18)
C4	0.0480 (17)	0.068 (2)	0.121 (3)	−0.0186 (16)	0.0290 (19)	−0.019 (2)
C5	0.0355 (15)	0.086 (2)	0.104 (3)	−0.0010 (15)	−0.0050 (16)	−0.032 (2)
C6	0.083 (3)	0.073 (2)	0.063 (2)	0.0062 (18)	−0.0147 (18)	−0.0048 (15)

Geometric parameters (Å, º)

Cl1—Ag1	2.3117 (11)	C1—C6^ii	1.477 (4)
Cl1—K1	3.2568 (14)	C1—H1A	0.970
Ag1—Cl1^i	2.3117 (11)	C1—H1B	0.970
K1—O2	2.783 (2)	C2—C3	1.484 (4)
K1—O2^ii	2.783 (2)	C2—H2A	0.970
K1—O3^ii	2.8145 (19)	C2—H2B	0.970
K1—O3	2.8145 (19)	C3—H3A	0.970
K1—O1^ii	2.830 (2)	C3—H3B	0.970
K1—O1	2.830 (2)	C4—C5	1.471 (5)
K1—Cl1^ii	3.2568 (14)	C4—H4A	0.970
O1—C2	1.409 (4)	C4—H4B	0.970
O1—C1	1.430 (4)	C5—H5A	0.970
O2—C4	1.405 (4)	C5—H5B	0.970
O2—C3	1.413 (3)	C6—C1^ii	1.477 (4)
O3—C6	1.415 (3)	C6—H6A	0.970
O3—C5	1.419 (3)	C6—H6B	0.970
Ag1—Cl1—K1	93.96 (4)	C5—O3—K1	112.68 (16)
Cl1^i—Ag1—Cl1	180.0	O1—C1—C6^ii	109.6 (3)
O2—K1—O2^ii	180.0	O1—C1—H1A	109.7
O2—K1—O3^ii	120.16 (6)	C6^ii—C1—H1A	109.7
O2^ii—K1—O3^ii	59.84 (6)	O1—C1—H1B	109.7
O2—K1—O3	59.84 (6)	C6^ii—C1—H1B	109.7
O2^ii—K1—O3	120.16 (6)	H1A—C1—H1B	108.2
O3^ii—K1—O3	180.0	O1—C2—C3	109.4 (2)
O2—K1—O1^ii	119.12 (6)	O1—C2—H2A	109.8
O2^ii—K1—O1^ii	60.88 (6)	C3—C2—H2A	109.8
O3^ii—K1—O1^ii	119.26 (6)	O1—C2—H2B	109.8
O3—K1—O1^ii	60.74 (6)	C3—C2—H2B	109.8
O2—K1—O1	60.88 (6)	H2A—C2—H2B	108.2
O2^ii—K1—O1	119.12 (6)	O2—C3—C2	108.2 (2)
O3^ii—K1—O1	60.74 (6)	O2—C3—H3A	110.1
O3—K1—O1	119.26 (6)	C2—C3—H3A	110.1
O1^ii—K1—O1	180.0	O2—C3—H3B	110.1
O2—K1—Cl1^ii	104.35 (5)	C2—C3—H3B	110.1
O2^ii—K1—Cl1^ii	75.65 (5)	H3A—C3—H3B	108.4
O3^ii—K1—Cl1^ii	96.71 (5)	O2—C4—C5	108.6 (3)
O3—K1—Cl1^ii	83.29 (5)	O2—C4—H4A	110.0
O1^ii—K1—Cl1^ii	80.62 (4)	C5—C4—H4A	110.0
O1—K1—Cl1^ii	99.38 (4)	O2—C4—H4B	110.0
O2—K1—Cl1	75.65 (5)	C5—C4—H4B	110.0
O2^ii—K1—Cl1	104.35 (5)	H4A—C4—H4B	108.4
O3^ii—K1—Cl1	83.29 (5)	O3—C5—C4	109.9 (3)
O3—K1—Cl1	96.71 (5)	O3—C5—H5A	109.7
O1^ii—K1—Cl1	99.38 (4)	C4—C5—H5A	109.7
O1—K1—Cl1	80.62 (4)	O3—C5—H5B	109.7
Cl1^ii—K1—Cl1	180.0	C4—C5—H5B	109.7
C2—O1—C1	112.0 (2)	H5A—C5—H5B	108.2
C2—O1—K1	110.46 (17)	O3—C6—C1^ii	108.9 (3)
C1—O1—K1	110.70 (17)	O3—C6—H6A	109.9
C4—O2—C3	114.2 (2)	C1^ii—C6—H6A	109.9
C4—O2—K1	116.99 (17)	O3—C6—H6B	109.9
C3—O2—K1	114.25 (16)	C1^ii—C6—H6B	109.9
C6—O3—C5	113.9 (3)	H6A—C6—H6B	108.3
C6—O3—K1	114.53 (18)
Ag1—Cl1—K1—O2	176.84 (5)	Cl1^ii—K1—O2—C3	−77.49 (18)
Ag1—Cl1—K1—O2^ii	−3.16 (5)	Cl1—K1—O2—C3	102.51 (18)
Ag1—Cl1—K1—O3^ii	−59.64 (5)	O2—K1—O3—C6	−152.6 (2)
Ag1—Cl1—K1—O3	120.36 (5)	O2^ii—K1—O3—C6	27.4 (2)
Ag1—Cl1—K1—O1^ii	59.01 (5)	O1^ii—K1—O3—C6	13.5 (2)
Ag1—Cl1—K1—O1	−120.99 (5)	O1—K1—O3—C6	−166.5 (2)
O2—K1—O1—C2	20.34 (18)	Cl1^ii—K1—O3—C6	96.4 (2)
O2^ii—K1—O1—C2	−159.66 (18)	Cl1—K1—O3—C6	−83.6 (2)
O3^ii—K1—O1—C2	−145.9 (2)	O2—K1—O3—C5	−20.37 (19)
O3—K1—O1—C2	34.1 (2)	O2^ii—K1—O3—C5	159.63 (19)
Cl1^ii—K1—O1—C2	121.62 (18)	O1^ii—K1—O3—C5	145.7 (2)
Cl1—K1—O1—C2	−58.38 (18)	O1—K1—O3—C5	−34.3 (2)
O2—K1—O1—C1	145.0 (2)	Cl1^ii—K1—O3—C5	−131.3 (2)
O2^ii—K1—O1—C1	−35.0 (2)	Cl1—K1—O3—C5	48.7 (2)
O3^ii—K1—O1—C1	−21.23 (18)	C2—O1—C1—C6^ii	178.3 (3)
O3—K1—O1—C1	158.77 (18)	K1—O1—C1—C6^ii	54.5 (3)
Cl1^ii—K1—O1—C1	−113.71 (19)	C1—O1—C2—C3	−177.8 (2)
Cl1—K1—O1—C1	66.29 (19)	K1—O1—C2—C3	−53.9 (3)
O3^ii—K1—O2—C4	166.4 (2)	C4—O2—C3—C2	173.3 (2)
O3—K1—O2—C4	−13.6 (2)	K1—O2—C3—C2	−48.3 (3)
O1^ii—K1—O2—C4	−27.5 (2)	O1—C2—C3—O2	70.3 (3)
O1—K1—O2—C4	152.5 (2)	C3—O2—C4—C5	−178.1 (2)
Cl1^ii—K1—O2—C4	59.7 (2)	K1—O2—C4—C5	44.7 (3)
Cl1—K1—O2—C4	−120.3 (2)	C6—O3—C5—C4	−175.2 (3)
O3^ii—K1—O2—C3	29.3 (2)	K1—O3—C5—C4	52.2 (3)
O3—K1—O2—C3	−150.7 (2)	O2—C4—C5—O3	−64.7 (3)
O1^ii—K1—O2—C3	−164.62 (17)	C5—O3—C6—C1^ii	−177.8 (3)
O1—K1—O2—C3	15.38 (17)	K1—O3—C6—C1^ii	−46.1 (3)

Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+1, −y+1, −z+1.