Guanidinium tetraoxidorhenate(VII)

The coordination geometry of the Re atom in the title compound, (CH₆N₃)[ReO₄], is tetra­hedral. The structure consists of alternating cationic and anionic layers parallel to the (10) plane; the layers are held in a three-dimensional structure by N—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](e-O) = 0.002 Å
• R factor = 0.018
• wR factor = 0.040
• Data-to-parameter ratio = 32.9

checkCIF/PLATON results

No syntax errors found



Alert level B
ABSTM02_ALERT_3_B  The ratio of expected to reported Tmax/Tmin(RR) is > 1.50
            Tmin and Tmax reported:      0.192     0.346
            Tmin and Tmax expected:      0.109     0.308
            RR =      1.573
            Please check that your absorption correction is appropriate.
PLAT060_ALERT_3_B Ratio Tmax/Tmin (Exp-to-Rep) (too) Large .......       1.56

Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.89

Alert level G
ABSTM02_ALERT_3_G  When printed, the submitted absorption T values will be
            replaced by the scaled T values. Since the ratio of scaled T's
            is identical to the ratio of reported T values, the scaling
            does not imply a change to the absorption corrections used in
            the study.
            Ratio of Tmax expected/reported      0.892
            Tmax scaled      0.308 Tmin scaled      0.171
PLAT794_ALERT_5_G Check Predicted Bond Valency for Re1         (7)       7.72

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

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

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S1. Comment

The title compound, (I) (Fig. 1), contains slightly distorted tetrahedral ReO₄^- anions with Re—O distances from 1.720 (2) to 1.733 (2) Å (Table 1).

Guanidinium cations act as proton donors in a number of weak hydrogen bonds (Fig. 2, Table 2). In contrast to the structure of 2,2,8,8-tetraallyl-3,4,6,7,8,9-hexahydro-2H-pyrimidino(1,2 - a)pyrimidinium tetraoxorhenate(VII) (Leibnitz et al., 2001), only one O atom of each tetraoxoanion is bonded to the same cation.

The structure of (I) can be described as alternating cationic and anionic layers parallel to the (120) plane (Fig. 3). Similar alternating layers are present in the structures of C(NH₂)₃ClO₄ (Koziol, 1984) and C(NH₂)₃BF₄ (Kozak et al., 1987), but there is an essential difference in the orientation of tetrahedral anions between cationic layers. In (I), two O atoms of each anion participate in hydrogen bonding with one cationic layer and two - with another cationic layer. In C(NH₂)₃ClO₄ and isostructural C(NH₂)₃BF₄, three O or F atoms of tetrahedral anion are connected with one cationic layer and one atom - with another layer. The resulting hydrogen bond net in (I) is three-dimensional.

Related literature

The structures of tetraoxorhenates of several cyclic derivatives of guanidinium are described by Leibnitz et al. (2001) and Tamm et al. (2004). Guanidium perchlorate is reported by Koziol (1984) and guaninidium tetrafluoroborate by Kozak et al. (1987).

S2. Experimental

Synthesis of (I) was carried out as a neutralization reaction by dissolution of stoichiometric quantity of guanidine under intensive stirring in 0.2 M water solution of HReO₄ at room temperature, followed by evaporation of the resulting solution over P₂O₅. The compound was recrystallized from ethanol.

S3. Refinement

The H atoms of NH₂ groups were refined in idealized geometrical positions with displacement parameters being equal to 1.2 times U_eq of the attached N atoms.

Largest electron density peak on the final difference Fourier-synthesis is 1.593 e Å^-3 (0.94 Å from Re1), the deepest hole is -2.902 e Å^-3 (0.69 Å from Re1).

Computing details

Data collection: APEX2 (Bruker, 0000); cell refinement: SAINT-Plus (Bruker, 1998); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: SHELXTL97 (Sheldrick, 1997b); software used to prepare material for publication: SHELXTL97.

Figures

	Fig. 1. A view of (I), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are represented by circles of arbitrary size. Dashed line indicates the hydrogen-bonding interaction.
	Fig. 2. A pattern of the hydrogen-bonding of one guanidinium cation in (I).
	Fig. 3. The packing of (I) showing three-dimensional net of hydrogen bonds.

Guanidinium tetraoxidorhenate(VII) [C(NH₂)₃][ReO₄]

Crystal data

(CH6N3)[ReO4]	Z = 2
Mr = 310.29	F(000) = 280
Triclinic, P1	Dx = 3.334 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 4.9657 (4) Å	Cell parameters from 8692 reflections
b = 7.7187 (7) Å	θ = 2.8–35.0°
c = 8.4423 (7) Å	µ = 19.61 mm^−1
α = 75.314 (4)°	T = 100 K
β = 88.707 (5)°	Plate, colourless
γ = 80.985 (5)°	0.12 × 0.10 × 0.06 mm
V = 309.09 (5) Å^3

Data collection

Bruker KappaAPEXII area-detector diffractometer	2698 independent reflections
Radiation source: fine-focus sealed tube	2506 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.027
ω and φ scans	θmax = 35.0°, θmin = 2.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −7→8
Tmin = 0.192, Tmax = 0.346	k = −12→12
11709 measured reflections	l = −13→13

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)] = 0.018	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.040	H-atom parameters constrained
S = 1.11	w = 1/[σ^2(Fo^2) + (0.0177P)^2 + 0.58P] where P = (Fo^2 + 2Fc^2)/3
2698 reflections	(Δ/σ)max = 0.002
82 parameters	Δρmax = 1.59 e Å^−3
0 restraints	Δρmin = −2.90 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
Re1	0.00024 (2)	0.252412 (14)	0.685859 (11)	0.00754 (3)
O1	−0.1246 (5)	0.3316 (3)	0.4871 (2)	0.0164 (4)
O2	−0.0731 (5)	0.0363 (3)	0.7671 (3)	0.0185 (4)
O3	0.3487 (5)	0.2424 (3)	0.6862 (3)	0.0150 (4)
O4	−0.1391 (5)	0.3927 (3)	0.8075 (3)	0.0139 (4)
N1	0.4480 (5)	0.1966 (4)	0.0569 (3)	0.0129 (4)
H1A	0.5021	0.2371	−0.0438	0.015*
H1B	0.3283	0.1212	0.0769	0.015*
N2	0.4610 (5)	0.1881 (4)	0.3302 (3)	0.0125 (4)
H2A	0.5238	0.2229	0.4119	0.015*
H2B	0.3413	0.1127	0.3486	0.015*
N3	0.7270 (5)	0.3627 (3)	0.1487 (3)	0.0117 (4)
H3A	0.7809	0.4031	0.0479	0.014*
H3B	0.7927	0.3977	0.2294	0.014*
C1	0.5471 (5)	0.2493 (3)	0.1790 (3)	0.0087 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Re1	0.00736 (5)	0.00912 (5)	0.00673 (4)	−0.00250 (3)	0.00081 (3)	−0.00245 (3)
O1	0.0142 (10)	0.0288 (12)	0.0075 (8)	−0.0076 (9)	−0.0017 (7)	−0.0042 (8)
O2	0.0139 (10)	0.0106 (9)	0.0292 (12)	−0.0040 (8)	0.0018 (8)	−0.0004 (8)
O3	0.0097 (9)	0.0179 (10)	0.0179 (9)	−0.0032 (8)	0.0006 (7)	−0.0046 (8)
O4	0.0161 (10)	0.0155 (9)	0.0112 (8)	−0.0009 (8)	0.0026 (7)	−0.0066 (7)
N1	0.0165 (11)	0.0169 (11)	0.0075 (8)	−0.0088 (9)	−0.0008 (8)	−0.0033 (8)
N2	0.0154 (11)	0.0157 (11)	0.0075 (8)	−0.0073 (9)	0.0022 (7)	−0.0021 (8)
N3	0.0148 (11)	0.0119 (10)	0.0100 (9)	−0.0064 (8)	0.0005 (7)	−0.0028 (7)
C1	0.0092 (11)	0.0081 (10)	0.0083 (9)	−0.0006 (8)	−0.0008 (8)	−0.0016 (8)

Geometric parameters (Å, º)

Re1—O1	1.727 (2)	C1—N2	1.330 (3)
Re1—O2	1.728 (2)	N2—H2A	0.8800
Re1—O3	1.720 (2)	N2—H2B	0.8800
Re1—O4	1.733 (2)	C1—N3	1.323 (3)
C1—N1	1.330 (3)	N3—H3A	0.8800
N1—H1A	0.8800	N3—H3B	0.8800
N1—H1B	0.8800
O1—Re1—O2	109.53 (12)	C1—N2—H2A	120.0
O1—Re1—O3	109.35 (11)	C1—N2—H2B	120.0
O1—Re1—O4	111.43 (11)	H2A—N2—H2B	120.0
O2—Re1—O3	108.35 (11)	C1—N3—H3A	120.0
O2—Re1—O4	109.43 (11)	C1—N3—H3B	120.0
O3—Re1—O4	108.69 (11)	H3A—N3—H3B	120.0
C1—N1—H1A	120.0	N1—C1—N2	119.1 (2)
C1—N1—H1B	120.0	N1—C1—N3	119.9 (2)
H1A—N1—H1B	120.0	N2—C1—N3	120.9 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O3^i	0.88	2.41	3.101 (3)	136
N1—H1A···O4^ii	0.88	2.45	3.177 (3)	140
N1—H1B···O2^iii	0.88	2.10	2.911 (3)	153
N2—H2A···O1^iv	0.88	2.22	2.966 (3)	142
N2—H2A···O3	0.88	2.49	3.164 (3)	134
N2—H2B···O2^iii	0.88	2.27	3.037 (3)	145
N3—H3A···O4^ii	0.88	2.08	2.901 (3)	155
N3—H3B···O1^iv	0.88	2.14	2.907 (3)	146
N3—H3B···O4^v	0.88	2.50	3.080 (3)	124

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