1,4-Diazo­niabicyclo­[2.2.2]octane tetra­aqua­tetra­chloro­lanthanate(III) chloride

Ritchie, L.K.; Harrison, W.T.A.

doi:10.1107/S1600536806016898

metal-organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 62| Part 6| June 2006| Pages m1255-m1257

https://doi.org/10.1107/S1600536806016898

1,4-Diazoniabicyclo[2.2.2]octane tetraaquatetrachlorolanthanate(III) chloride

Lyndsey K. Ritchie ^a and William T. A. Harrison ^a ^*

^aDepartment of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, Scotland
^*Correspondence e-mail: w.harrison@abdn.ac.uk

(Received 3 May 2006; accepted 8 May 2006; online 10 May 2006)

The title compound, (C₆H₁₄N₂)[LaCl₄(H₂O)₄]Cl, is built up from organic cations, [La(H₂O)₄Cl₄]⁻ complex anions and uncoordinated chloride ions. The previously unseen rare-earth-containing complex ion is irregular in shape. A network of O—H⋯Cl and N—H⋯Cl hydrogen bonds helps to establish the structure. Prominent among these are two well defined trifurcated N—H⋯(Cl,Cl,Cl) interactions. The La atom, one Cl atom, two N atoms and two C atoms possess site symmetry m.

Comment

The title compound, (I), which contains a new La/Cl/H₂O complex ion, complements known adducts of lanthanum chloride with O-donor ligands such as the polymeric [LaCl₃(C₇H₈O₂)₂]_n (C₇H₈O₂ is 2,6-dimethyl-4-pyrone; Bisi Castellani & Coda, 1985 ) and the dimeric [La₂(H₂O)₆Cl₈(C₆H₈N)₂] (C₆H₈N is 4-picoline; Mackenstedt & Urland, 1993 ). Although various materials containing [LaCl₆]³⁻ (Matsumoto et al., 2002 ), [La(H₂O)₈]³⁺ (Hardie et al., 2001 ) and [La(H₂O)₉]³⁺ complex ions (Harrowfield et al., 1983 ) have been described, the only monomeric La/Cl/H₂O complex reported in version 5.27 of the Cambridge Structural Database (Allen, 2002 ) contains [La(H₂O)₆Cl₂]⁺ ions (Urland, 1985 ), although no atomic coordinates are available.

The [La(H₂O)₄Cl₄]⁻ species in (I) (Fig. 1) is generated from the unique atoms by mirror symmetry, with La1 and Cl1 lying on the reflecting plane. Refinements placing Cl2 on the plane led to a highly anisotropic displacement ellipsoid for this atom, and the final refinement cycles placed it just off the mirror plane, disordered over two symmetry-related positions [Cl2⋯Cl2ⁱ = 0.530 (4) Å; symmetry code: (i) x, $[{1\over 2}]$ − y, z]. The resulting LaO₄Cl₄ polyhedron is irregular in shape, although the mean La—O and La—Cl bond lengths of 2.547 (2) and 2.8960 (9) Å, respectively, are normal. The geometrical parameters for the 1,4-diazoniabicyclo[2.2.2]octane cation are also unexceptional (Bremner & Harrison, 2003 ).

As well as electrostatic forces, the component species in (I) are held together by a network of O—H⋯Cl and N—H⋯Cl hydrogen bonds (Table 2). The most distinctive of these are two trifurcated N—H⋯(Cl,Cl,Cl) interactions, one from each NH group of the C₆H₁₄N₂²⁺ cation. This results (Fig. 2) in (001) sheets in which [100] columns of cations and anions alternate with respect to the [010] direction. Every trio of acceptor chloride ions (two Cl3 atoms bound to different La atoms and one free Cl4 species) accepts a trifurcated hydrogen bond from both N1/H6 and N2/H7. The average bond angles at H6 and H7 are 108 and 107°, respectively.

The [100] columns of [La(H₂O)₄Cl₄]⁻ anions interact by way of two hydrogen bonds from the O2 water molecule to two chloride ion acceptors. Crystal symmetry results in all the anions in one (001) layer pointing in the same direction. The uncoordinated chloride ion participates in an O—H⋯Cl⋯H—O bridge between adjacent anion columns (Fig. 2). Still further O—H⋯Cl hydrogen bonds help to consolidate the inter-layer packing, to result in a dense three-dimensional network (Fig. 3).

Figure 1
View of (I)

, showing 30% probability displacement ellipsoids (arbitrary spheres for the H atoms). Only one orientation of the disordered atom Cl2 is shown. [Symmetry codes: (i) x, $[{1\over 2}]$ − y, z; (ii) x, $[{3\over 2}]$ − y, z.]

Figure 2
View down [001] of part of a (C₆H₁₄N₂)·[La(H₂O)₄Cl₄]·Cl layer in (I)

, with hydrogen bonds shown as dashed lines. C-bound H atoms have been omitted for clarity and only one orientation of the disordered atom Cl2 is shown. [Symmetry codes: (i) x, $[{1\over 2}]$ − y, z; (ii) x + 1, y, z; (iii) x, y + 1, z; (iv) x − 1, $[{1\over 2}]$ − y, z; (v) x − 1, y, z; (vi) x − 1, y + 1, z.]

Figure 3
The packing in (I)

, viewed down [100]. Drawing conventions as in Fig. 2

Experimental

0.1 M LaCl₃, 1 M HCl and solid 1,4-diazabicyclo[2.2.2]octane (C₆H₁₂N₂) were mixed in a Petri dish in a 1:1:1 molar ratio, resulting in a clear solution. Small block-like crystals of (I) appeared as the water slowly evaporated over a few days.

Crystal data

(C₆H₁₄N₂)[LaCl₄(H₂O)₄]Cl
M_r = 502.42
Orthorhombic, P n m a
a = 7.5005 (3) Å
b = 9.1759 (4) Å
c = 25.0388 (10) Å
V = 1723.27 (12) Å³
Z = 4
D_x = 1.937 Mg m⁻³
Mo Kα radiation
μ = 3.26 mm⁻¹
T = 293 (2) K
Block, colourless
0.35 × 0.21 × 0.16 mm

Data collection

Bruker SMART 1000 CCD diffractometer
ω scans
Absorption correction: multi-scan (SADABS; Bruker, 1999 ) T_min = 0.395, T_max = 0.624
18229 measured reflections
3279 independent reflections
2971 reflections with I > 2σ(I)
R_int = 0.020
θ_max = 32.5°

Refinement

Refinement on F²
R[F² > 2σ(F²)] = 0.020
wR(F²) = 0.044
S = 1.14
3279 reflections
101 parameters
H-atom parameters constrained
w = 1/[σ²(F_o²) + (0.0199P)² + 0.3724P] where P = (F_o² + 2F_c²)/3
(Δ/σ)_max = 0.001
Δρ_max = 0.58 e Å⁻³
Δρ_min = −0.43 e Å⁻³
Extinction correction: SHELXL97
Extinction coefficient: 0.00056 (9)

Table 1
Selected bond lengths (Å)

La1—O2	2.5240 (18)
La1—O3	2.5492 (11)
La1—O1	2.5650 (16)
La1—Cl2	2.8310 (8)
La1—Cl3	2.8524 (4)
La1—Cl1	3.0482 (6)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯Cl3ⁱ	0.83	2.49	3.2429 (14)	151
O2—H2⋯Cl2ⁱⁱ	0.84	2.28	3.1035 (19)	166
O2—H2⋯Cl2ⁱⁱⁱ	0.84	2.28	3.1035 (19)	166
O2—H3⋯Cl1ⁱⁱ	0.82	2.41	3.1834 (19)	159
O3—H4⋯Cl4^iv	0.83	2.33	3.1542 (12)	173
O3—H5⋯Cl1^v	0.93	2.26	3.1765 (12)	173
N1—H6⋯Cl3ⁱⁱⁱ	0.91	2.67	3.2930 (15)	127
N1—H6⋯Cl3^vi	0.91	2.67	3.2930 (15)	127
N1—H6⋯Cl4ⁱⁱ	0.91	2.71	3.3086 (19)	125
N2—H7⋯Cl4	0.91	2.54	3.208 (2)	131
N2—H7⋯Cl3^vii	0.91	2.80	3.3962 (17)	125
N2—H7⋯Cl3^viii	0.91	2.80	3.3962 (17)	125
Symmetry codes: (i) -x+1, -y, -z+1; (ii) x-1, y, z; (iii) $[x-1, -y+{\script{1\over 2}}, z]$ ; (iv) x, y-1, z; (v) $[x-{\script{1\over 2}}, y, -z+{\script{3\over 2}}]$ ; (vi) x-1, y+1, z; (vii) x, y+1, z; (viii) $[x, -y+{\script{1\over 2}}, z]$ .

The O-bound H atoms were located in difference maps and refined as riding in their as-found relative locations. The C- and N-bound H atoms were placed in idealized locations (C—H = 0.97 and N—H = 0.91 Å) and refined as riding. The constraint U_iso(H) = 1.2U_eq(carrier) was applied in all cases.

Data collection: SMART (Bruker, 1999); cell refinement: SAINT-Plus (Bruker, 1999); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997; molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536806016898/sg2023sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536806016898/sg2023Isup2.hkl

Computing details top

Data collection: SMART (Bruker, 1999); cell refinement: SAINT-Plus (Bruker, 1999); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997; molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97.

1,4-Diazoniabicyclo[2.2.2]octane tetraaquatetrachlorolanthanate(III) chloride top

Crystal data top

(C₆H₁₄N₂)[LaCl₄(H₂O)₄]Cl	F(000) = 984
M_r = 502.42	D_x = 1.937 Mg m⁻³
Orthorhombic, Pnma	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2n	Cell parameters from 5263 reflections
a = 7.5005 (3) Å	θ = 2.4–32.5°
b = 9.1759 (4) Å	µ = 3.26 mm⁻¹
c = 25.0388 (10) Å	T = 293 K
V = 1723.27 (12) Å³	Block, colourless
Z = 4	0.35 × 0.21 × 0.16 mm

Data collection top

Bruker SMART 1000 CCD diffractometer	3279 independent reflections
Radiation source: fine-focus sealed tube	2971 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.020
ω scans	θ_max = 32.5°, θ_min = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 1999)	h = −11→6
T_min = 0.395, T_max = 0.624	k = −13→13
18229 measured reflections	l = −37→37

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difmap (O-H) and geom (others)
R[F² > 2σ(F²)] = 0.020	H-atom parameters constrained
wR(F²) = 0.044	w = 1/[σ²(F_o²) + (0.0199P)² + 0.3724P] where P = (F_o² + 2F_c²)/3
S = 1.14	(Δ/σ)_max = 0.001
3279 reflections	Δρ_max = 0.58 e Å⁻³
101 parameters	Δρ_min = −0.43 e Å⁻³
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.00056 (9)

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
La1	0.590349 (16)	0.2500	0.617775 (4)	0.01947 (4)
O1	0.4503 (3)	0.2500	0.52432 (6)	0.0339 (4)
H1	0.4507	0.1732	0.5065	0.041*
O2	0.2541 (2)	0.2500	0.62157 (7)	0.0391 (4)
H2	0.1698	0.2500	0.5993	0.047*
H3	0.1848	0.2500	0.6468	0.047*
O3	0.50337 (19)	0.09026 (12)	0.69689 (4)	0.0369 (3)
H4	0.5053	0.0001	0.7008	0.044*
H5	0.4731	0.1284	0.7299	0.044*
Cl1	0.90617 (9)	0.2500	0.69439 (2)	0.03609 (13)
Cl2	0.90460 (11)	0.2211 (2)	0.55605 (3)	0.0453 (6)	0.50
Cl3	0.55658 (6)	−0.04244 (4)	0.580485 (16)	0.03060 (8)
C1	0.1477 (2)	0.61758 (19)	0.65549 (8)	0.0352 (4)
H1A	0.1859	0.6177	0.6925	0.042*
H1B	0.1944	0.5306	0.6385	0.042*
C2	−0.0537 (2)	0.6177 (2)	0.65261 (9)	0.0390 (4)
H2A	−0.0946	0.5310	0.6342	0.047*
H2B	−0.1032	0.6169	0.6884	0.047*
C3	0.1595 (3)	0.7500	0.57038 (10)	0.0414 (6)
H3A	0.2059	0.6643	0.5525	0.050*
C4	−0.0427 (4)	0.7500	0.56802 (10)	0.0430 (7)
H4A	−0.0842	0.8357	0.5490	0.052*
N1	−0.1154 (2)	0.7500	0.62359 (7)	0.0251 (4)
H6	−0.2367	0.7500	0.6222	0.030*
N2	0.2166 (3)	0.7500	0.62779 (7)	0.0291 (4)
H7	0.3378	0.7500	0.6293	0.035*
Cl4	0.54768 (8)	0.7500	0.70889 (2)	0.02892 (11)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
La1	0.01944 (6)	0.02101 (5)	0.01796 (6)	0.000	0.00004 (4)	0.000
O1	0.0509 (11)	0.0277 (7)	0.0230 (7)	0.000	−0.0084 (7)	0.000
O2	0.0214 (8)	0.0584 (11)	0.0373 (9)	0.000	−0.0009 (7)	0.000
O3	0.0609 (9)	0.0255 (5)	0.0241 (5)	−0.0054 (6)	0.0066 (6)	−0.0002 (4)
Cl1	0.0366 (3)	0.0475 (3)	0.0242 (2)	0.000	−0.0057 (2)	0.000
Cl2	0.0253 (3)	0.0869 (18)	0.0236 (3)	−0.0029 (5)	0.0034 (3)	−0.0010 (4)
Cl3	0.0393 (2)	0.02462 (15)	0.02786 (17)	0.00411 (14)	−0.00325 (15)	−0.00412 (13)
C1	0.0304 (8)	0.0320 (8)	0.0433 (10)	0.0059 (7)	−0.0021 (7)	0.0040 (7)
C2	0.0310 (9)	0.0329 (8)	0.0532 (11)	−0.0023 (7)	−0.0025 (8)	0.0125 (8)
C3	0.0277 (12)	0.0739 (19)	0.0226 (11)	0.000	0.0010 (9)	0.000
C4	0.0271 (12)	0.077 (2)	0.0248 (11)	0.000	−0.0022 (9)	0.000
N1	0.0182 (8)	0.0301 (9)	0.0270 (9)	0.000	−0.0015 (7)	0.000
N2	0.0188 (8)	0.0396 (10)	0.0290 (9)	0.000	−0.0003 (7)	0.000
Cl4	0.0298 (3)	0.0300 (2)	0.0269 (2)	0.000	−0.0018 (2)	0.000

Geometric parameters (Å, º) top

La1—O2	2.5240 (18)	C1—C2	1.512 (2)
La1—O3ⁱ	2.5492 (11)	C1—H1A	0.9700
La1—O3	2.5492 (11)	C1—H1B	0.9700
La1—O1	2.5650 (16)	C2—N1	1.489 (2)
La1—Cl2	2.8310 (8)	C2—H2A	0.9700
La1—Cl2ⁱ	2.8310 (8)	C2—H2B	0.9700
La1—Cl3	2.8524 (4)	C3—N2	1.500 (3)
La1—Cl3ⁱ	2.8524 (4)	C3—C4	1.518 (4)
La1—Cl1	3.0482 (6)	C3—H3A	0.9700
O1—H1	0.8335	C4—N1	1.494 (3)
O2—H2	0.8433	C4—H4A	0.9700
O2—H3	0.8172	N1—C2ⁱⁱ	1.489 (2)
O3—H4	0.8330	N1—H6	0.9100
O3—H5	0.9262	N2—C1ⁱⁱ	1.491 (2)
Cl2—Cl2ⁱ	0.530 (4)	N2—H7	0.9100
C1—N2	1.491 (2)

O2—La1—O3ⁱ	73.44 (5)	La1—O2—H2	136.4
O2—La1—O3	73.44 (5)	La1—O2—H3	131.6
O3ⁱ—La1—O3	70.20 (5)	H2—O2—H3	92.0
O2—La1—O1	67.98 (6)	La1—O3—H4	131.2
O3ⁱ—La1—O1	127.16 (4)	La1—O3—H5	122.6
O3—La1—O1	127.16 (4)	H4—O3—H5	105.9
O2—La1—Cl2	148.49 (4)	Cl2ⁱ—Cl2—La1	84.63 (4)
O3ⁱ—La1—Cl2	133.72 (4)	N2—C1—C2	108.86 (14)
O3—La1—Cl2	125.70 (5)	N2—C1—H1A	109.9
O1—La1—Cl2	80.97 (5)	C2—C1—H1A	109.9
O2—La1—Cl2ⁱ	148.49 (4)	N2—C1—H1B	109.9
O3ⁱ—La1—Cl2ⁱ	125.70 (5)	C2—C1—H1B	109.9
O3—La1—Cl2ⁱ	133.72 (4)	H1A—C1—H1B	108.3
O1—La1—Cl2ⁱ	80.97 (5)	N1—C2—C1	109.54 (15)
Cl2—La1—Cl2ⁱ	10.73 (8)	N1—C2—H2A	109.8
O2—La1—Cl3	85.617 (16)	C1—C2—H2A	109.8
O3ⁱ—La1—Cl3	140.58 (3)	N1—C2—H2B	109.8
O3—La1—Cl3	71.99 (3)	C1—C2—H2B	109.8
O1—La1—Cl3	70.429 (9)	H2A—C2—H2B	108.2
Cl2—La1—Cl3	78.89 (4)	N2—C3—C4	108.8 (2)
Cl2ⁱ—La1—Cl3	89.04 (4)	N2—C3—H3A	109.9
O2—La1—Cl3ⁱ	85.617 (16)	C4—C3—H3A	109.9
O3ⁱ—La1—Cl3ⁱ	71.99 (3)	N1—C4—C3	109.2 (2)
O3—La1—Cl3ⁱ	140.58 (3)	N1—C4—H4A	109.8
O1—La1—Cl3ⁱ	70.429 (9)	C3—C4—H4A	109.8
Cl2—La1—Cl3ⁱ	89.04 (4)	C2ⁱⁱ—N1—C2	109.3 (2)
Cl2ⁱ—La1—Cl3ⁱ	78.89 (4)	C2ⁱⁱ—N1—C4	109.94 (13)
Cl3—La1—Cl3ⁱ	140.349 (16)	C2—N1—C4	109.94 (13)
O2—La1—Cl1	138.84 (4)	C2ⁱⁱ—N1—H6	109.2
O3ⁱ—La1—Cl1	73.13 (3)	C2—N1—H6	109.2
O3—La1—Cl1	73.13 (3)	C4—N1—H6	109.2
O1—La1—Cl1	153.18 (4)	C1ⁱⁱ—N2—C1	109.12 (19)
Cl2—La1—Cl1	72.33 (2)	C1ⁱⁱ—N2—C3	110.29 (13)
Cl2ⁱ—La1—Cl1	72.33 (2)	C1—N2—C3	110.29 (13)
Cl3—La1—Cl1	105.963 (9)	C1ⁱⁱ—N2—H7	109.0
Cl3ⁱ—La1—Cl1	105.963 (9)	C1—N2—H7	109.0
La1—O1—H1	119.0	C3—N2—H7	109.0

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···Cl3ⁱⁱⁱ	0.83	2.49	3.2429 (14)	151
O2—H2···Cl2^iv	0.84	2.28	3.1035 (19)	166
O2—H2···Cl2^v	0.84	2.28	3.1035 (19)	166
O2—H3···Cl1^iv	0.82	2.41	3.1834 (19)	159
O3—H4···Cl4^vi	0.83	2.33	3.1542 (12)	173
O3—H5···Cl1^vii	0.93	2.26	3.1765 (12)	173
N1—H6···Cl3^v	0.91	2.67	3.2930 (15)	127
N1—H6···Cl3^viii	0.91	2.67	3.2930 (15)	127
N1—H6···Cl4^iv	0.91	2.71	3.3086 (19)	125
N2—H7···Cl4	0.91	2.54	3.208 (2)	131
N2—H7···Cl3^ix	0.91	2.80	3.3962 (17)	125
N2—H7···Cl3ⁱ	0.91	2.80	3.3962 (17)	125

Symmetry codes: (i) x, −y+1/2, z; (iii) −x+1, −y, −z+1; (iv) x−1, y, z; (v) x−1, −y+1/2, z; (vi) x, y−1, z; (vii) x−1/2, y, −z+3/2; (viii) x−1, y+1, z; (ix) x, y+1, z.

Acknowledgements

LKR thanks the Carnegie Trust for the Universities of Scotland for a vacation scholarship.

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