Pyridinium diaqua­bis­(methyl­enediphospho­nato-κ2O,O′)chromate(III) tetra­hydrate

Van der Merwe, K.; Visser, H.G.; Venter, J.A.

doi:10.1107/S1600536810028990

metal-organic compounds

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ISSN: 2056-9890

Volume 66| Part 8| August 2010| Pages m1011-m1012

https://doi.org/10.1107/S1600536810028990

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Pyridinium diaquabis(methylenediphosphonato-κ²O,O′)chromate(III) tetrahydrate

Kina Van der Merwe,^a ^* Hendrik G. Visser ^a and J. A. Venter ^a

^aDepartment of Chemistry, University of the Free State, PO Box 339, Bloemfontein 9330, South Africa
^*Correspondence e-mail: kinavdmerwe@gmail.com

(Received 14 July 2010; accepted 20 July 2010; online 24 July 2010)

In the title complex, (C₅H₆N)[Cr(CH₄O₆P₂)₂(H₂O)₂]·4H₂O, the Cr^III atom, lying on an inversion centre, is coordinated by two bidentate methylene diphosphonate ligands and two water molecules in a distorted octahedral coordination geometry. The pyridinium cation is located on an inversion centre, with an N atom and a C atom sharing a position each at a half occupancy. A three-dimensional network is constructed by O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds between the pyridinium cation, complex anion and uncoordinated water molecules.

Related literature

For general background to metal-organic frameworks with diphosphonic acids, see: Barthelet et al. (2002 ). For related structures, see: Byun et al. (2006 ); Suh et al. (1997 ); Van der Merwe et al. (2009 ); Visser et al. (2010 ).

Experimental

Crystal data

(C₅H₆N)[Cr(CH₄O₆P₂)₂(H₂O)₂]·4H₂O
M_r = 588.17
Triclinic, $[P \overline 1]$
a = 7.206 (5) Å
b = 7.485 (5) Å
c = 10.984 (5) Å
α = 107.085 (5)°
β = 106.128 (5)°
γ = 94.496 (5)°
V = 535.7 (6) Å³
Z = 1
Mo Kα radiation
μ = 0.92 mm⁻¹
T = 100 K
0.22 × 0.16 × 0.08 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; (Bruker, 2001 ) T_min = 0.843, T_max = 0.931
8784 measured reflections
2632 independent reflections
2483 reflections with I > 2σ(I)
R_int = 0.020

Refinement

R[F² > 2σ(F²)] = 0.024
wR(F²) = 0.070
S = 1.05
2632 reflections
179 parameters
16 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.47 e Å⁻³
Δρ_min = −0.62 e Å⁻³

Table 1
Selected bond lengths (Å)

Cr1—O1	1.991 (4)
Cr1—O2	1.956 (4)
Cr1—O7	1.964 (4)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H4⋯O6ⁱ	0.97	2.49	3.346 (7)	147
C4—H4A⋯O9ⁱⁱ	0.93	2.16	2.93 (7)	140
N1—H1⋯O9ⁱⁱ	0.86	2.32	3.03 (5)	141
O1—H1A⋯O6ⁱ	0.80 (6)	1.83 (6)	2.634 (6)	176 (9)
O1—H1B⋯O4ⁱⁱⁱ	0.83 (6)	1.87 (6)	2.704 (6)	177 (9)
O3—H3⋯O8^iv	0.82	1.83	2.629 (6)	163
O5—H6⋯O4ⁱⁱ	0.83 (5)	1.80 (5)	2.619 (6)	175 (10)
O8—H7⋯O6^v	0.83 (6)	1.86 (6)	2.687 (6)	171 (9)
O8—H8⋯O9	0.85 (7)	1.94 (8)	2.748 (7)	158 (11)
O9—H9A⋯O4	0.83 (6)	2.00 (6)	2.833 (6)	179 (10)
O9—H10⋯O8^vi	0.84 (7)	1.99 (7)	2.820 (7)	174 (13)
Symmetry codes: (i) -x+1, -y+2, -z+1; (ii) -x, -y+1, -z+1; (iii) x+1, y, z; (iv) -x+1, -y+2, -z+2; (v) x, y, z+1; (vi) -x, -y+2, -z+2.

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT-Plus (Bruker, 2007); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: DIAMOND (Brandenburg, 1999 ); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810028990/hy2333sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810028990/hy2333Isup2.hkl

checkCIF report

Comment top

The title compound forms part of an ongoing study in our group involving methylene diphosphonate and its coordination to various metal cores. (Van der Merwe et al., 2009; Visser et al., 2010). Diphosphonic acids are useful for the synthesis of metal-organic frameworks exhibiting microporous properties (Barthelet et al., 2002).

The Cr^III ion in the title complex is in a distorted octahedral environment (Fig. 1), with Cr—O bond distances ranging from 1.956 (4) to 1.991 (4) Å (Table 1). All the bond distances and angles are well within the normal range (Byun et al., 2006; Suh et al., 1997). The pyridinium cation is located on an inversion centre and an N atom and a C atom share a position at a half occupancy for each atom. A three-dimensional network is provided by numerous hydrogen bonds between the pyridinium cation, complex anion and uncoordinated water molecules (Table 2).

Related literature top

For general background to metal-organic frameworks with diphosphonic acids, see: Barthelet et al. (2002). For related structures, see: Byun et al. (2006); Suh et al. (1997); Van der Merwe et al. (2009); Visser et al. (2010).

Experimental top

CrCl₃.6H₂O (0.092 g, 0.347 mmol) was dissolved in water (40 ml) and ammonium hydroxide was gradually added dropwise in order to precipitate Cr(III) hydroxide. Methylene diphosphonate (0.347 g, 2 mmol) was added to the Cr(OH)₃ and water (40 ml). The reaction solution was heated on an oil bath for 5 h at 100°C, after which pyridine (10 ml) was added to the solution. Boiling H₂O (30 ml) was added and the solution was centrifuged. Green crystals of the title compound crystallized from the filtrate after several days.

Structure description top

For general background to metal-organic frameworks with diphosphonic acids, see: Barthelet et al. (2002). For related structures, see: Byun et al. (2006); Suh et al. (1997); Van der Merwe et al. (2009); Visser et al. (2010).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT-Plus (Bruker, 2007); data reduction: SAINT-Plus (Bruker, 2007); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. Molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level. [Symmetry code: (i) 1-x, 1-y, 1-z.]

Pyridinium diaquabis(methylenediphosphonato-κ²O,O')chromate(III) tetrahydrate top

Crystal data top

(C₅H₆N)[Cr(CH₄O₆P₂)₂(H₂O)₂]·4H₂O	Z = 1
M_r = 588.17	F(000) = 303
Triclinic, P1	D_x = 1.823 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.206 (5) Å	Cell parameters from 6300 reflections
b = 7.485 (5) Å	θ = 0.8–0.9°
c = 10.984 (5) Å	µ = 0.92 mm⁻¹
α = 107.085 (5)°	T = 100 K
β = 106.128 (5)°	Cuboid, green
γ = 94.496 (5)°	0.22 × 0.16 × 0.08 mm
V = 535.7 (6) Å³

Data collection top

Bruker APEXII CCD diffractometer	2483 reflections with I > 2σ(I)
φ and ω scans	R_int = 0.020
Absorption correction: multi-scan (SADABS; (Bruker, 2001)	θ_max = 28.3°, θ_min = 4.1°
T_min = 0.843, T_max = 0.931	h = −9→9
8784 measured reflections	k = −9→6
2632 independent reflections	l = −14→14

Refinement top

Refinement on F²	16 restraints
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F² > 2σ(F²)] = 0.024	w = 1/[σ²(F_o²) + (0.0342P)² + 0.4874P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.070	(Δ/σ)_max < 0.001
S = 1.05	Δρ_max = 0.47 e Å⁻³
2632 reflections	Δρ_min = −0.62 e Å⁻³
179 parameters

Crystal data top

(C₅H₆N)[Cr(CH₄O₆P₂)₂(H₂O)₂]·4H₂O	γ = 94.496 (5)°
M_r = 588.17	V = 535.7 (6) Å³
Triclinic, P1	Z = 1
a = 7.206 (5) Å	Mo Kα radiation
b = 7.485 (5) Å	µ = 0.92 mm⁻¹
c = 10.984 (5) Å	T = 100 K
α = 107.085 (5)°	0.22 × 0.16 × 0.08 mm
β = 106.128 (5)°

Data collection top

Bruker APEXII CCD diffractometer	2632 independent reflections
Absorption correction: multi-scan (SADABS; (Bruker, 2001)	2483 reflections with I > 2σ(I)
T_min = 0.843, T_max = 0.931	R_int = 0.020
8784 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.024	16 restraints
wR(F²) = 0.070	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	Δρ_max = 0.47 e Å⁻³
2632 reflections	Δρ_min = −0.62 e Å⁻³
179 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
Cr1	0.5000	0.5000	0.5000	0.0082 (3)
P2	0.2173 (2)	0.79359 (19)	0.41325 (14)	0.0086 (4)
P1	0.29362 (19)	0.7622 (2)	0.69142 (14)	0.0085 (4)
O2	0.4491 (6)	0.6457 (6)	0.6635 (4)	0.0110 (8)
O5	−0.0069 (6)	0.7069 (6)	0.3539 (4)	0.0128 (8)
O3	0.3700 (6)	0.8943 (6)	0.8418 (4)	0.0134 (8)
H3	0.4774	0.9569	0.8570	0.020*
O7	0.3373 (6)	0.6353 (6)	0.3947 (4)	0.0113 (8)
O9	−0.0373 (8)	0.7358 (7)	0.8942 (5)	0.0235 (10)
O1	0.7325 (6)	0.6953 (6)	0.5401 (4)	0.0121 (8)
C1	0.2683 (8)	0.9145 (8)	0.5903 (6)	0.0108 (10)
H4	0.3885	1.0063	0.6226	0.013*
H5	0.1633	0.9841	0.6027	0.013*
O4	0.0957 (6)	0.6494 (6)	0.6673 (4)	0.0118 (8)
O8	0.2601 (7)	0.9720 (7)	1.1133 (5)	0.0198 (10)
N1	0.381 (7)	0.479 (8)	0.070 (5)	0.028 (12)	0.50
H1	0.3025	0.4691	0.1145	0.034*	0.50
C4	0.381 (8)	0.466 (10)	0.078 (5)	0.024 (10)	0.50
H4A	0.3051	0.4405	0.1294	0.029*	0.50
C3	0.5612 (13)	0.5896 (11)	0.1367 (8)	0.0312 (17)
H3A	0.6025	0.6454	0.2295	0.037*
C2	0.3206 (12)	0.3837 (11)	−0.0627 (8)	0.0322 (17)
H2	0.2008	0.3014	−0.1034	0.039*
O6	0.2543 (6)	0.9385 (6)	0.3492 (4)	0.0133 (8)
H8	0.193 (16)	0.882 (13)	1.042 (9)	0.06 (3)*
H7	0.262 (14)	0.950 (13)	1.184 (7)	0.03 (2)*
H1B	0.844 (10)	0.677 (12)	0.577 (8)	0.03 (2)*
H1A	0.731 (13)	0.806 (9)	0.573 (8)	0.025*
H6	−0.032 (11)	0.597 (8)	0.352 (9)	0.03 (3)*
H9A	0.002 (13)	0.710 (13)	0.828 (8)	0.03 (2)*
H10	−0.110 (17)	0.817 (16)	0.888 (14)	0.07 (4)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cr1	0.0067 (6)	0.0081 (6)	0.0107 (6)	0.0020 (4)	0.0035 (4)	0.0035 (5)
P2	0.0072 (6)	0.0076 (7)	0.0120 (7)	0.0015 (5)	0.0031 (5)	0.0042 (5)
P1	0.0068 (6)	0.0084 (7)	0.0103 (7)	0.0011 (5)	0.0032 (5)	0.0025 (5)
O2	0.0103 (18)	0.0121 (19)	0.0119 (19)	0.0050 (15)	0.0043 (15)	0.0042 (15)
O5	0.0077 (18)	0.011 (2)	0.019 (2)	0.0004 (15)	0.0019 (15)	0.0053 (16)
O3	0.0110 (18)	0.013 (2)	0.0126 (19)	−0.0004 (15)	0.0036 (15)	0.0006 (16)
O7	0.0103 (18)	0.0116 (19)	0.0136 (19)	0.0046 (15)	0.0047 (15)	0.0048 (15)
O9	0.029 (3)	0.024 (3)	0.021 (2)	0.004 (2)	0.014 (2)	0.007 (2)
O1	0.0082 (18)	0.0088 (19)	0.019 (2)	0.0013 (15)	0.0034 (16)	0.0043 (16)
C1	0.010 (2)	0.008 (2)	0.013 (3)	0.0014 (19)	0.003 (2)	0.003 (2)
O4	0.0085 (18)	0.0114 (19)	0.0153 (19)	0.0000 (14)	0.0039 (15)	0.0043 (15)
O8	0.018 (2)	0.026 (2)	0.013 (2)	−0.0028 (18)	0.0032 (17)	0.0052 (19)
N1	0.04 (2)	0.028 (18)	0.033 (19)	0.019 (13)	0.019 (16)	0.023 (13)
C4	0.026 (18)	0.019 (15)	0.018 (15)	−0.001 (12)	−0.008 (12)	0.008 (13)
C3	0.042 (5)	0.020 (3)	0.021 (3)	0.007 (3)	−0.004 (3)	0.006 (3)
C2	0.033 (4)	0.023 (4)	0.029 (4)	0.000 (3)	−0.008 (3)	0.009 (3)
O6	0.0148 (19)	0.0108 (19)	0.016 (2)	0.0016 (15)	0.0053 (16)	0.0073 (16)

Geometric parameters (Å, º) top

Cr1—O1	1.991 (4)	O1—H1B	0.83 (6)
Cr1—O2	1.956 (4)	O1—H1A	0.80 (6)
Cr1—O7	1.964 (4)	C1—H4	0.9700
P2—O6	1.499 (4)	C1—H5	0.9700
P2—O7	1.519 (4)	O8—H8	0.85 (7)
P2—O5	1.568 (4)	O8—H7	0.83 (6)
P2—C1	1.804 (6)	N1—C2	1.34 (5)
P1—O4	1.512 (4)	N1—C3	1.36 (4)
P1—O4	1.512 (4)	N1—H1	0.8600
P1—O2	1.515 (4)	C4—C3	1.40 (5)
P1—O3	1.568 (4)	C4—C2	1.41 (5)
P1—C1	1.797 (6)	C4—H4A	0.9300
O5—H6	0.83 (5)	C3—C2ⁱ	1.371 (13)
O3—H3	0.8200	C3—H3A	0.9300
O9—H9A	0.83 (6)	C2—C3ⁱ	1.371 (13)
O9—H10	0.84 (7)	C2—H2	0.9300

O2ⁱⁱ—Cr1—O2	180.00 (15)	P2—O5—H6	114 (5)
O2ⁱⁱ—Cr1—O7	88.35 (17)	P1—O3—H3	109.5
O2—Cr1—O7	91.65 (17)	P2—O7—Cr1	140.0 (3)
O2ⁱⁱ—Cr1—O7ⁱⁱ	91.65 (17)	H9A—O9—H10	108 (10)
O2—Cr1—O7ⁱⁱ	88.35 (17)	Cr1—O1—H1B	119 (6)
O7—Cr1—O7ⁱⁱ	180.0 (2)	Cr1—O1—H1A	120 (6)
O2ⁱⁱ—Cr1—O1ⁱⁱ	90.51 (17)	H1B—O1—H1A	107 (9)
O2—Cr1—O1ⁱⁱ	89.49 (17)	P1—C1—P2	114.8 (3)
O7—Cr1—O1ⁱⁱ	90.81 (18)	P1—C1—H4	108.6
O7ⁱⁱ—Cr1—O1ⁱⁱ	89.19 (18)	P2—C1—H4	108.6
O2ⁱⁱ—Cr1—O1	89.49 (17)	P1—C1—H5	108.6
O2—Cr1—O1	90.51 (17)	P2—C1—H5	108.6
O7—Cr1—O1	89.19 (18)	H4—C1—H5	107.5
O7ⁱⁱ—Cr1—O1	90.81 (18)	H8—O8—H7	114 (10)
O1ⁱⁱ—Cr1—O1	180.0 (3)	C2—N1—C3	123 (4)
O6—P2—O7	114.8 (2)	C2—N1—H1	118.3
O6—P2—O5	107.8 (2)	C3—N1—H1	118.3
O7—P2—O5	109.7 (2)	C3—C4—C2	116 (5)
O6—P2—C1	108.2 (3)	C3—C4—H4A	122.1
O7—P2—C1	109.0 (2)	C2—C4—H4A	122.1
O5—P2—C1	107.1 (2)	N1—C3—C2ⁱ	118 (2)
O4—P1—O2	115.5 (2)	C2ⁱ—C3—C4	122 (3)
O4—P1—O2	115.5 (2)	N1—C3—H3A	121.1
O4—P1—O3	107.9 (2)	C2ⁱ—C3—H3A	121.1
O4—P1—O3	107.9 (2)	C4—C3—H3A	116.7
O2—P1—O3	108.6 (2)	N1—C2—C3ⁱ	119 (2)
O4—P1—C1	110.1 (2)	C3ⁱ—C2—C4	122 (2)
O4—P1—C1	110.1 (2)	N1—C2—H2	120.7
O2—P1—C1	107.6 (2)	C3ⁱ—C2—H2	120.7
O3—P1—C1	106.9 (3)	C4—C2—H2	117.1
P1—O2—Cr1	134.1 (2)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H4···O6ⁱⁱⁱ	0.97	2.49	3.346 (7)	147
C4—H4A···O9^iv	0.93	2.16	2.93 (7)	140
N1—H1···O9^iv	0.86	2.32	3.03 (5)	141
O1—H1A···O6ⁱⁱⁱ	0.80 (6)	1.83 (6)	2.634 (6)	176 (9)
O1—H1B···O4^v	0.83 (6)	1.87 (6)	2.704 (6)	177 (9)
O3—H3···O8^vi	0.82	1.83	2.629 (6)	163
O5—H6···O4^iv	0.83 (5)	1.80 (5)	2.619 (6)	175 (10)
O8—H7···O6^vii	0.83 (6)	1.86 (6)	2.687 (6)	171 (9)
O8—H8···O9	0.85 (7)	1.94 (8)	2.748 (7)	158 (11)
O9—H9A···O4	0.83 (6)	2.00 (6)	2.833 (6)	179 (10)
O9—H10···O8^viii	0.84 (7)	1.99 (7)	2.820 (7)	174 (13)

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

Experimental details

Crystal data
Chemical formula	(C₅H₆N)[Cr(CH₄O₆P₂)₂(H₂O)₂]·4H₂O
M_r	588.17
Crystal system, space group	Triclinic, P1
Temperature (K)	100
a, b, c (Å)	7.206 (5), 7.485 (5), 10.984 (5)
α, β, γ (°)	107.085 (5), 106.128 (5), 94.496 (5)
V (Å³)	535.7 (6)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	0.92
Crystal size (mm)	0.22 × 0.16 × 0.08

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; (Bruker, 2001)
T_min, T_max	0.843, 0.931
No. of measured, independent and observed [I > 2σ(I)] reflections	8784, 2632, 2483
R_int	0.020
(sin θ/λ)_max (Å⁻¹)	0.666

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.024, 0.070, 1.05
No. of reflections	2632
No. of parameters	179
No. of restraints	16
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.47, −0.62

Computer programs: APEX2 (Bruker, 2007), SAINT-Plus (Bruker, 2007), SHELXTL (Sheldrick, 2008), DIAMOND (Brandenburg, 1999).

Selected bond lengths (Å) top

Cr1—O1	1.991 (4)	Cr1—O7	1.964 (4)
Cr1—O2	1.956 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H4···O6ⁱ	0.97	2.49	3.346 (7)	147
C4—H4A···O9ⁱⁱ	0.93	2.16	2.93 (7)	140
N1—H1···O9ⁱⁱ	0.86	2.32	3.03 (5)	141
O1—H1A···O6ⁱ	0.80 (6)	1.83 (6)	2.634 (6)	176 (9)
O1—H1B···O4ⁱⁱⁱ	0.83 (6)	1.87 (6)	2.704 (6)	177 (9)
O3—H3···O8^iv	0.82	1.83	2.629 (6)	163
O5—H6···O4ⁱⁱ	0.83 (5)	1.80 (5)	2.619 (6)	175 (10)
O8—H7···O6^v	0.83 (6)	1.86 (6)	2.687 (6)	171 (9)
O8—H8···O9	0.85 (7)	1.94 (8)	2.748 (7)	158 (11)
O9—H9A···O4	0.83 (6)	2.00 (6)	2.833 (6)	179 (10)
O9—H10···O8^vi	0.84 (7)	1.99 (7)	2.820 (7)	174 (13)

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

Acknowledgements

The University of the Free State and Professor A. Roodt are gratefully acknowledged for financial support.

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