Tetra­aqua­bis(biuret-κ2O,O′)yttrium(III) trichloride

Harrison, W.T.A.

doi:10.1107/S1600536808008659

metal-organic compounds

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Volume 64| Part 5| May 2008| Page m619

doi:10.1107/S1600536808008659

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Tetraaquabis(biuret-κ²O,O′)yttrium(III) trichloride

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 27 March 2008; accepted 31 March 2008; online 2 April 2008)

In the title compound, [Y(C₂H₅N₃O₂)₂(H₂O)₄]Cl₃, the Y³⁺ ion (site symmetry 2) is bonded to eight O atoms (arising from two O,O′-bidentate biuret molecules and four water molecules) in a distorted square-antiprismatic arrangement. A network of N—H⋯O, N—H⋯Cl and O—H⋯Cl hydrogen bonds help to establish the packing, leading to a three-dimensional network. One of the chloride ions has site symmetry 2.

Related literature

For related structures, see: Carugo et al. (1992 ); Haddad (1987 , 1988 ). For related literature, see: Bernstein et al. (1995 ). For valence-sum calculations, see: Brese & O'Keeffe (1991 ).

Experimental

Crystal data

[Y(C₂H₅N₃O₂)₂(H₂O)₄]Cl₃
M_r = 473.50
Monoclinic, C 2/c
a = 7.6510 (4) Å
b = 13.2534 (7) Å
c = 17.2547 (9) Å
β = 100.817 (1)°
V = 1718.57 (16) Å³
Z = 4
Mo Kα radiation
μ = 3.90 mm⁻¹
T = 293 (2) K
0.36 × 0.24 × 0.14 mm

Data collection

Bruker SMART1000 CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 1999 ) T_min = 0.340, T_max = 0.611 (expected range = 0.322–0.579)
8075 measured reflections
3105 independent reflections
2464 reflections with I > 2σ(I)
R_int = 0.019

Refinement

R[F² > 2σ(F²)] = 0.025
wR(F²) = 0.059
S = 0.98
3105 reflections
101 parameters
H-atom parameters constrained
Δρ_max = 0.37 e Å⁻³
Δρ_min = −0.34 e Å⁻³

Table 1
Selected bond lengths (Å)

Y1—O1	2.3157 (11)
Y1—O2	2.3349 (11)
Y1—O4	2.3536 (12)
Y1—O3	2.3660 (10)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O1ⁱ	0.86	2.10	2.9111 (18)	157
N1—H2⋯Cl1ⁱⁱ	0.86	2.39	3.1897 (17)	155
N2—H3⋯Cl1ⁱⁱ	0.86	2.53	3.3184 (14)	153
N3—H4⋯Cl1ⁱⁱⁱ	0.86	2.54	3.3633 (15)	161
N3—H5⋯Cl1^iv	0.86	2.54	3.3232 (15)	151
O3—H6⋯Cl1^v	0.80	2.39	3.1607 (12)	161
O3—H7⋯Cl2^vi	0.79	2.27	3.0504 (12)	168
O4—H8⋯Cl1	0.75	2.45	3.2028 (13)	177
O4—H9⋯Cl2	0.80	2.40	3.1238 (12)	150
Symmetry codes: (i) $[-x+1, y, -z+{\script{3\over 2}}]$ ; (ii) $[x+{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ ; (iii) $[x-{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ ; (iv) -x, -y, -z+1; (v) $[-x-{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1]$ ; (vi) x-1, y, z.

Data collection: SMART (Bruker, 1999); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808008659/tk2260sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808008659/tk2260Isup2.hkl

checkCIF report

Comment top

No complexes of yttrium(III) with biuret (biur), H₂N—CO—NH—CO—NH₂ (or C₂H₅N₃O₂) have been structurally characterized. The structures of two samarium-biuret complexes, Sm(biur)₄.(NO₃)₃ (Haddad, 1987) and Sm(biur)₄.(ClO₄)₃ (Haddad, 1988) have been described. In both cases, an SmO₈ square antiprismatic coordination arises for the metal ion. Based on X-ray photographs, it was suggested that all the Ln(biur)₄.(NO₃)₃ and Ln(biur)₄.(ClO₄)₃ compounds are isostructural with their samarium prototypes. In this paper, we describe the synthesis and structure of the title compound, (I).

Compound (I) is an ionic salt containing a new [Y(biur)₂(H₂O)₄]³⁺ complex ion. The complete complex ion is generated by crystallographic 2-fold symmetry, with the Y atom lying on the rotation axis. Two uncoordinated chloride ions, one of which has crystallographic site symmetry 2, complete the structure of (I), Fig. 1.

The resulting YO₈ polyhedral geometry in (I) (Table 1) is a distorted square antiprism (Fig. 2). The nominal square face formed by atoms O1, O2, O1ⁱ and O2ⁱ (i = -x, y, 3/2 - z) is reasonably regular, but the second face formed by the four water molecules (O3, O4, O3ⁱ and O4ⁱ) is much more distorted, and the diagonal O3···O3ⁱ and O4···O4ⁱ distances of 4.223 (2)Å and 3.5197 (19) Å, respectively, are very different. The Y1 atom deviates from the mean planes of O1/O2/O1ⁱ/O2ⁱ and O3/O4/O3ⁱ/O4ⁱ by 1.1616 (8) Å and 1.3151 (9) Å, respectively. The two O atom mean planes are constrained to be parallel by symmetry. The bond valence sum (Brese & O'Keeffe, 1991) for Y1 of 3.34 in (I) indicates that its valence requirement is easily satisfied by this geometry.

The O,O-bidenate coordination of the biuret molecule to the yttrium ion in (I) results in a six-membered chelate ring that is non-planar. As noted previously (Carugo et al., 1992), the biuret molecule can be regarded as two planar amide fragments linked by the NH bridge. Here, the dihedral angle betwen the N1/C1/O1/N2 and N2/C2/O2/N3 units is 5.06 (10)°. The yttrium cation deviates from the N1/C1/O1/N2 and N2/C2/O2/N3 mean planes by 0.894 (4) Å and 0.606 (4) Å, respectively.

The component species in (I) are linked by a dense array of N—H···O, N—H···Cl and O—H···Cl hydrogen bonds (Table 2) resulting in a three-dimensional network. Of note is the N—H···O hydrogen bond, which results in [100] chains (Fig. 3) of cations, in which R²₂(8) loops (Bernstein et al., 1995) linking the molecules are apparent.

Related literature top

For related structures, see: Carugo et al. (1992); Haddad (1987, 1988). For related literature, see: Bernstein et al. (1995). For valence-sum calculations, see: Brese & O'Keeffe (1991).

Experimental top

0.1 M Aqueous solutions of YCl₃ (10 ml) and biuret (10 ml) were mixed and a small quantity of dilute hydrochloric acid was added, to result in a colourless solution. Colourless blocks of (I) grew over several days as the water slowly evaporated.

Computing details top

Data collection: SMART (Bruker, 1999); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. View of the molecular structure of (I) showing 50% displacement ellipsoids (arbitrary spheres for the H atoms). Symmetry code: (i) -x, y, 3/2 - z.
	Fig. 2. Detail of (I) showing the distorted square antiprismatic coordination of the Y atom. Symmetry code: (i) -x, y, 3/2 - z.
	Fig. 3. Fragment of a [100] chain of cations in (I) with the hydrogen bonds indicated by double-dashed lines. Symmetry codes: (i) 1 - x, y, 3/2 - z; (ii) x + 1, y, z.

Tetraaquabis(biuret-κ²O,O')yttrium(III) trichloride top

Crystal data top

[Y(C₂H₅N₃O₂)₂(H₂O)₄]Cl₃	F(000) = 952
M_r = 473.50	D_x = 1.830 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 3637 reflections
a = 7.6510 (4) Å	θ = 3.1–32.4°
b = 13.2534 (7) Å	µ = 3.90 mm⁻¹
c = 17.2547 (9) Å	T = 293 K
β = 100.817 (1)°	Block, colourless
V = 1718.57 (16) Å³	0.36 × 0.24 × 0.14 mm
Z = 4

Data collection top

Bruker SMART1000 CCD diffractometer	3105 independent reflections
Radiation source: fine-focus sealed tube	2464 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.019
ω scans	θ_max = 32.6°, θ_min = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 1999)	h = −11→11
T_min = 0.340, T_max = 0.611	k = −20→19
8075 measured reflections	l = −16→26

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)] = 0.025	Hydrogen site location: difmap (O-H) and geom (N-H)
wR(F²) = 0.059	H-atom parameters constrained
S = 0.98	w = 1/[σ²(F_o²) + (0.0303P)²] where P = (F_o² + 2F_c²)/3
3105 reflections	(Δ/σ)_max < 0.001
101 parameters	Δρ_max = 0.37 e Å⁻³
0 restraints	Δρ_min = −0.34 e Å⁻³

Crystal data top

[Y(C₂H₅N₃O₂)₂(H₂O)₄]Cl₃	V = 1718.57 (16) Å³
M_r = 473.50	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 7.6510 (4) Å	µ = 3.90 mm⁻¹
b = 13.2534 (7) Å	T = 293 K
c = 17.2547 (9) Å	0.36 × 0.24 × 0.14 mm
β = 100.817 (1)°

Data collection top

Bruker SMART1000 CCD diffractometer	3105 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 1999)	2464 reflections with I > 2σ(I)
T_min = 0.340, T_max = 0.611	R_int = 0.019
8075 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.025	0 restraints
wR(F²) = 0.059	H-atom parameters constrained
S = 0.98	Δρ_max = 0.37 e Å⁻³
3105 reflections	Δρ_min = −0.34 e Å⁻³
101 parameters

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
Y1	0.0000	0.107273 (15)	0.7500	0.02386 (6)
Cl1	−0.04205 (5)	0.33346 (3)	0.50811 (2)	0.03905 (10)
Cl2	0.5000	0.29705 (5)	0.7500	0.03992 (14)
O1	0.25038 (14)	0.02884 (9)	0.72093 (7)	0.0348 (3)
O2	−0.08317 (13)	0.01042 (8)	0.63600 (7)	0.0329 (2)
N1	0.45654 (18)	−0.01014 (13)	0.64850 (10)	0.0476 (4)
H1	0.5399	0.0182	0.6817	0.057*
H2	0.4804	−0.0382	0.6068	0.057*
N2	0.17105 (17)	−0.05973 (11)	0.60525 (8)	0.0332 (3)
H3	0.2113	−0.0980	0.5724	0.040*
N3	−0.10477 (19)	−0.11253 (11)	0.54451 (9)	0.0410 (3)
H4	−0.2191	−0.1099	0.5351	0.049*
H5	−0.0506	−0.1546	0.5193	0.049*
C1	0.2922 (2)	−0.01064 (12)	0.66153 (10)	0.0308 (3)
C2	−0.0118 (2)	−0.05156 (11)	0.59806 (9)	0.0295 (3)
O3	−0.23875 (15)	0.18780 (9)	0.66560 (7)	0.0377 (3)
H6	−0.2731	0.1747	0.6201	0.045*
H7	−0.3170	0.2159	0.6812	0.045*
O4	0.11867 (16)	0.22520 (10)	0.67195 (8)	0.0519 (4)
H8	0.0828	0.2492	0.6326	0.062*
H9	0.2176	0.2465	0.6742	0.062*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Y1	0.02161 (9)	0.02849 (10)	0.02041 (9)	0.000	0.00117 (7)	0.000
Cl1	0.0364 (2)	0.0491 (2)	0.0297 (2)	0.00110 (17)	0.00118 (17)	−0.00610 (18)
Cl2	0.0316 (3)	0.0479 (3)	0.0418 (3)	0.000	0.0107 (2)	0.000
O1	0.0255 (5)	0.0467 (6)	0.0309 (6)	0.0049 (5)	0.0014 (5)	−0.0080 (5)
O2	0.0282 (5)	0.0358 (6)	0.0327 (6)	0.0034 (5)	0.0004 (5)	−0.0092 (5)
N1	0.0266 (7)	0.0778 (11)	0.0394 (8)	−0.0078 (7)	0.0089 (6)	−0.0204 (8)
N2	0.0266 (6)	0.0415 (7)	0.0315 (7)	0.0016 (6)	0.0053 (5)	−0.0088 (6)
N3	0.0321 (7)	0.0459 (8)	0.0426 (8)	−0.0014 (6)	0.0012 (6)	−0.0179 (7)
C1	0.0271 (7)	0.0350 (8)	0.0293 (8)	0.0013 (6)	0.0025 (6)	0.0004 (7)
C2	0.0290 (7)	0.0320 (7)	0.0261 (7)	−0.0009 (6)	0.0021 (6)	0.0012 (6)
O3	0.0353 (6)	0.0498 (7)	0.0253 (6)	0.0145 (5)	−0.0011 (5)	−0.0026 (5)
O4	0.0390 (7)	0.0677 (9)	0.0436 (7)	−0.0157 (6)	−0.0061 (6)	0.0281 (7)

Geometric parameters (Å, º) top

Y1—O1ⁱ	2.3157 (11)	N1—H2	0.8600
Y1—O1	2.3157 (11)	N2—C1	1.374 (2)
Y1—O2	2.3349 (11)	N2—C2	1.385 (2)
Y1—O2ⁱ	2.3349 (11)	N2—H3	0.8600
Y1—O4ⁱ	2.3536 (12)	N3—C2	1.329 (2)
Y1—O4	2.3536 (12)	N3—H4	0.8600
Y1—O3ⁱ	2.3660 (10)	N3—H5	0.8600
Y1—O3	2.3660 (10)	O3—H6	0.7990
O1—C1	1.2450 (19)	O3—H7	0.7934
O2—C2	1.2392 (18)	O4—H8	0.7541
N1—C1	1.318 (2)	O4—H9	0.8023
N1—H1	0.8600

O1ⁱ—Y1—O1	126.66 (6)	O4—Y1—O3	71.61 (4)
O1ⁱ—Y1—O2	80.21 (4)	O3ⁱ—Y1—O3	126.37 (6)
O1—Y1—O2	71.12 (4)	C1—O1—Y1	135.89 (10)
O1ⁱ—Y1—O2ⁱ	71.12 (4)	C2—O2—Y1	137.05 (10)
O1—Y1—O2ⁱ	80.21 (4)	C1—N1—H1	120.0
O2—Y1—O2ⁱ	113.30 (6)	C1—N1—H2	120.0
O1ⁱ—Y1—O4ⁱ	75.55 (5)	H1—N1—H2	120.0
O1—Y1—O4ⁱ	147.74 (4)	C1—N2—C2	124.22 (14)
O2—Y1—O4ⁱ	140.68 (4)	C1—N2—H3	117.9
O2ⁱ—Y1—O4ⁱ	87.51 (4)	C2—N2—H3	117.9
O1ⁱ—Y1—O4	147.74 (4)	C2—N3—H4	120.0
O1—Y1—O4	75.55 (5)	C2—N3—H5	120.0
O2—Y1—O4	87.51 (4)	H4—N3—H5	120.0
O2ⁱ—Y1—O4	140.68 (4)	O1—C1—N1	122.63 (15)
O4ⁱ—Y1—O4	96.78 (8)	O1—C1—N2	122.49 (14)
O1ⁱ—Y1—O3ⁱ	130.07 (4)	N1—C1—N2	114.87 (15)
O1—Y1—O3ⁱ	76.19 (4)	O2—C2—N3	122.60 (14)
O2—Y1—O3ⁱ	145.42 (4)	O2—C2—N2	122.84 (14)
O2ⁱ—Y1—O3ⁱ	70.89 (4)	N3—C2—N2	114.49 (15)
O4ⁱ—Y1—O3ⁱ	71.61 (4)	Y1—O3—H6	125.5
O4—Y1—O3ⁱ	73.53 (4)	Y1—O3—H7	123.2
O1ⁱ—Y1—O3	76.19 (4)	H6—O3—H7	107.8
O1—Y1—O3	130.07 (4)	Y1—O4—H8	133.0
O2—Y1—O3	70.89 (4)	Y1—O4—H9	132.0
O2ⁱ—Y1—O3	145.42 (4)	H8—O4—H9	94.3
O4ⁱ—Y1—O3	73.53 (4)

Symmetry code: (i) −x, y, −z+3/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1ⁱⁱ	0.86	2.10	2.9111 (18)	157
N1—H2···Cl1ⁱⁱⁱ	0.86	2.39	3.1897 (17)	155
N2—H3···Cl1ⁱⁱⁱ	0.86	2.53	3.3184 (14)	153
N3—H4···Cl1^iv	0.86	2.54	3.3633 (15)	161
N3—H5···Cl1^v	0.86	2.54	3.3232 (15)	151
O3—H6···Cl1^vi	0.80	2.39	3.1607 (12)	161
O3—H7···Cl2^vii	0.79	2.27	3.0504 (12)	168
O4—H8···Cl1	0.75	2.45	3.2028 (13)	177
O4—H9···Cl2	0.80	2.40	3.1238 (12)	150

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

Experimental details

Crystal data
Chemical formula	[Y(C₂H₅N₃O₂)₂(H₂O)₄]Cl₃
M_r	473.50
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	293
a, b, c (Å)	7.6510 (4), 13.2534 (7), 17.2547 (9)
β (°)	100.817 (1)
V (Å³)	1718.57 (16)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	3.90
Crystal size (mm)	0.36 × 0.24 × 0.14

Data collection
Diffractometer	Bruker SMART1000 CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 1999)
T_min, T_max	0.340, 0.611
No. of measured, independent and observed [I > 2σ(I)] reflections	8075, 3105, 2464
R_int	0.019
(sin θ/λ)_max (Å⁻¹)	0.758

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.025, 0.059, 0.98
No. of reflections	3105
No. of parameters	101
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.37, −0.34

Computer programs: SMART (Bruker, 1999), SAINT (Bruker, 1999), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).

Selected bond lengths (Å) top

Y1—O1	2.3157 (11)	Y1—O4	2.3536 (12)
Y1—O2	2.3349 (11)	Y1—O3	2.3660 (10)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1ⁱ	0.86	2.10	2.9111 (18)	157
N1—H2···Cl1ⁱⁱ	0.86	2.39	3.1897 (17)	155
N2—H3···Cl1ⁱⁱ	0.86	2.53	3.3184 (14)	153
N3—H4···Cl1ⁱⁱⁱ	0.86	2.54	3.3633 (15)	161
N3—H5···Cl1^iv	0.86	2.54	3.3232 (15)	151
O3—H6···Cl1^v	0.80	2.39	3.1607 (12)	161
O3—H7···Cl2^vi	0.79	2.27	3.0504 (12)	168
O4—H8···Cl1	0.75	2.45	3.2028 (13)	177
O4—H9···Cl2	0.80	2.40	3.1238 (12)	150

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

References

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ISSN: 2056-9890

Volume 64| Part 5| May 2008| Page m619

doi:10.1107/S1600536808008659

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access