Crystal structure of bis­[1-(2-hy­droxy­eth­yl)-2-methyl-5-nitro-1H-imidazole-κN3]silver(I) tetra­fluorido­borate methanol monosolvate

Palmer, J.H.; Upmacis, R.K.

doi:10.1107/S2056989015002819

research communications

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ISSN: 2056-9890

Volume 71| Part 3| March 2015| Pages 284-287

doi:10.1107/S2056989015002819

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Crystal structure of bis[1-(2-hydroxyethyl)-2-methyl-5-nitro-1H-imidazole-κN³]silver(I) tetrafluoridoborate methanol monosolvate

Joshua H. Palmer ^a and Rita K. Upmacis ^b ^*

^aDepartment of Chemistry, Columbia University, New York, NY 10027, USA, and ^bHaskins Laboratories, Dept. of Chemistry, Pace University, New York, NY 10038, USA
^*Correspondence e-mail: rupmacis@pace.edu

Edited by A. J. Lough, University of Toronto, Canada (Received 19 January 2015; accepted 9 February 2015; online 21 February 2015)

1-(2-Hydroxyethyl)-2-methyl-5-nitro-1H-imidazole (metronidazole, MET) is a medication that is used to treat infections by a variety of anaerobic organisms, but there are relatively few reports of the structures of metal compounds that exhibit coordination of metronidazole. We have demonstrated that MET reacts with AgBF₄ to give [Ag(MET)₂]BF₄·CH₃OH, in which the Ag^I cation is coordinated by two MET ligands with a trans arrangement. The structure of [Ag(MET)₂]BF₄ exhibits some interesting differences from its nitrate counterpart, [Ag(MET)₂]NO₃ [Fun et al. (2008). Acta Cryst. E64, m668]. For instance, although the two MET ligands of both [Ag(MET)₂]BF₄ and [Ag(MET)₂]NO₃ are almost coplanar, the former compound has an anti-like geometry with a molecular inversion center, but the latter has a syn-like arrangement. In the crystal, the BF₄⁻ anion is linked by an O—H⋯F hydrogen bond to the methanol solvent molecule, which is, in turn, linked to the cation by an O—H⋯O hydrogen bond; the components of the structure are linked by O—H⋯O hydrogen bonds, forming chains along [001]. One of the MET ligands and the BF₄⁻ anion are disordered over two sets of sites with ratios of refined occupancies 0.501 (17):0.499 (17) and 0.539 (19):0.461 (19), respectively.

Keywords: crystal structure; silver; metronidazole; Flagyl; tetrafluoridoborate; hydrogen bonding.

CCDC reference: 1048516

1. Chemical context

1-(2-Hydroxyethyl)-2-methyl-5-nitro-1H-imidazole, also known as metronidazole (MET) or Flagyl, is a medication used particularly for treatment of parasitic infections, such as trichomoniasis, amoebiasis and giardiasis, but is also effective against anaerobic bacteria (Freeman et al., 1997 ; Miljkovic et al., 2014 ; Soares et al., 2012 ; Samuelson, 1999 ; Lofmark et al., 2010 ). There are relatively few reports of the structures of metal compounds that exhibit coordination of MET. For example, with respect to silver, only the nitrate compound, [Ag(MET)₂]NO₃, has been structurally characterized by X-ray diffraction (Fun et al., 2008 ). Herein, we describe the structure of the tetrafluoridoborate derivative, [Ag(MET)₂]BF₄, which is obtained by addition of MET to AgBF₄ in methanol (see Scheme).

2. Structural commentary

Crystals of composition [Ag(MET)₂]BF₄·MeOH were obtained from a solution in methanol. The asymmetric unit consists of a silver cation, [Ag(MET)₂]⁺, a tetrafluoridoborate anion, BF₄⁻, and a solvent methanol molecule. The silver atom of [Ag(MET)₂]⁺ is coordinated by two MET ligands in a trans manner by their N³ nitrogen atoms, as illustrated in Fig. 1.

Figure 1
The molecular structure of the cation of the title compound, with displacement ellipsoids drawn at the 30% probability level. The disorder is not shown.

One of the MET ligands exhibits disorder resulting from rotation about the Ag—N bond [the dihedral angle between the planes of the disordered 5-membered rings is 11.0 (9)°]. The Ag—N bond lengths [Ag—N11 = 2.082 (15), Ag—N11A = 2.163 (16) and Ag—N21 = 2.1193 (15) Å] are comparable to those values in the nitrate derivative, [2.1489 (11) and 2.1475 (11) Å; Fun et al., 2008). There are, however, some interesting differences between the two compounds.

First, while the two MET ligands of both [Ag(MET)₂]BF₄ and [Ag(MET)₂]NO₃ are almost coplanar, the former compound has an anti-like geometry, and the latter has a syn-like arrangement. Thus, the C13—N11⋯N21—C23 torsion angle for [Ag(MET)₂]BF₄ is 160.8 (9)° [148.6 (11)° for the minor component of disorder], while the value for [Ag(MET)₂]NO₃ is 24.10° (Fun et al., 2008). These differences are illustrated in Fig. 2, which shows that the [Ag(MET)₂]⁺ unit of [Ag(MET)₂]BF₄ has an approximate inversion center at the Ag^I ion, whereas [Ag(MET)₂]NO₃ does not.

Figure 2
Comparison of the [Ag(MET)₂]⁺ units in [Ag(MET)₂]BF₄ (top) and [Ag(MET)₂]NO₃ (bottom).

A second interesting difference is that the N11—Ag—N21 angle of 175.7 (5)° for [Ag(MET)₂]BF₄ is much closer to 180° than is the corresponding value for [Ag(MET)₂]NO₃ [165.34 (4)°; Fun et al., 2008). It is possible that this could be attributed to the tetrafluoridoborate ligand being considered a non-coordinating ion relative to nitrate, and this is reflected by the fact that [Ag(MET)₂]NO₃ exhibits Ag⋯O contacts of 2.63 and 2.67 Å, which are comparable to distances in other silver nitrate compounds (Wu et al., 2012 ).

3. Supramolecular features

The hydroxyethyl group of one of the MET ligands [O21—H] serves as a donor in an intermolecular hydrogen-bonding interaction with the other hydroxyethyl group [O11—H] of an adjacent molecule. In turn, the latter hydroxyethyl group serves as a hydrogen-bond donor to a methanol molecule, which also hydrogen bonds to a tetrafluoridoborate anion. In the crystal, the components of the structure are linked into chains along [001] by the O—H⋯O hydrogen bonds (Table 1 and Fig. 3).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯F2	0.84	1.84	2.673 (9)	173
O11—H11A⋯O1	0.84	1.86	2.697 (10)	175
O21—H21A⋯O11ⁱ	0.84	1.91	2.726 (11)	164
O21—H21A⋯O11Aⁱ	0.84	1.87	2.712 (11)	176
Symmetry code: (i) x, y, z-1.

Figure 3
Part of a hydrogen-bonded chain along [001]. The disorder is not shown and hydrogen bonds are shown as dashed lines.

4. Database survey

In addition to coordination to silver, metronidazole has also been shown to coordinate to other metals, and structurally characterized compounds have been reported for Co (Galván-Tejada et al., 2002 ), Cu (Galván-Tejada et al., 2002; Barba-Behrens et al., 1991 ; Athar et al., 2005 ; Ratajczak-Sitarz et al., 1998 ; Bharti et al., 2002 ), Zn (Galván-Tejada et al., 2002), Ru (Wu et al., 2003 ; Kennedy et al., 2006 ), Rh (Dyson et al., 1990 ; Nothenberg et al., 1994 ), Pd (Bharti et al., 2002; De Bondt et al., 1994 ; Rochon et al., 1993 ) and Pt (Bharti et al., 2002; Bales et al., 1983 ). In these compounds, the coordination number of the central atom ranges from four for Cu, Zn, Pd and Pt to six for Ru and Rh.

5. Synthesis and crystallization

Crystals of composition [Ag(MET)₂]BF₄·MeOH were obtained by combining AgBF₄ with MET in a 1:2 molar ratio in methanol and allowing the solution to evaporate slowly at room temperature.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. Hydrogen atoms were refined using a riding-model approximation with C—H = 0.95–0.99 Å, O—H = 0.84 Å and U_iso(H) = 1.2U_eq(C,O). One of the MET ligands was refined as rotationally disordered with occupancies of 0.501 (17) and 0.499 (17) and the configurations were modeled using the SAME command in SHELXL2013 (Sheldrick, 2015 ). The tetrafluoridoborate counter-ion was also refined as disordered and was modeled with two site occupancies, 0.539 (19) and 0.461 (19).

Table 2
Experimental details

Crystal data
Chemical formula	[Ag(C₆H₉N₃O₃)₂]BF₄·CH₄O
M_r	569.04
Crystal system, space group	Triclinic, P $[\overline{1}]$
Temperature (K)	130
a, b, c (Å)	9.2592 (10), 10.5339 (10), 12.3995 (12)
α, β, γ (°)	106.940 (11), 92.788 (9), 112.439 (10)
V (Å³)	1051.7 (2)
Z	2
Radiation type	Mo Kα
μ (mm⁻¹)	1.04
Crystal size (mm)	1.00 × 0.51 × 0.31

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2013 )
T_min, T_max	0.551, 0.747
No. of measured, independent and observed [I > 2σ(I)] reflections	17164, 6401, 6107
R_int	0.023
(sin θ/λ)_max (Å⁻¹)	0.714

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.028, 0.067, 1.12
No. of reflections	6401
No. of parameters	440
No. of restraints	144
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.00, −1.03
Computer programs: APEX2 and SAINT (Bruker, 2013), SHELXS97 and SHELXTL (Sheldrick, 2008 ), SHELXL2013 (Sheldrick, 2015).

Supporting information

CCDC reference: 1048516

Crystal structure: contains datablock I. DOI: 10.1107/S2056989015002819/lh5749sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2056989015002819/lh5749Isup2.hkl

Supporting information file. DOI: 10.1107/S2056989015002819/lh5749Isup3.mol

Supporting information file. DOI: 10.1107/S2056989015002819/lh5749Isup4.txt

checkCIF report

Chemical context top

1-(2-hydroxyethyl)-2-methyl-5-nitro-1H-imidazole, also known as metronidazole (MET) or Flagyl, is a medication used particularly for treatment of parasitic infections, such as trichomoniasis, amoebiasis and giardiasis, but is also effective against anaerobic bacteria (Freeman et al., 1997; Miljkovic et al., 2014; Soares et al., 2012; Samuelson, 1999; Lofmark et al., 2010). There are relatively few reports of the structures of metal compounds that exhibit coordination of MET. For example, with respect to silver, only the nitrate compound, [Ag(MET)₂]NO₃, has been structurally characterized by X-ray diffraction (Fun et al., 2008). Herein, we describe the structure of the tetrafluoridoborate derivative, [Ag(MET)₂]BF₄, which is obtained by addition of MET to AgBF₄ in methanol (see Scheme below).

Structural commentary top

Crystals of composition [Ag(MET)₂]BF₄·MeOH were obtained from a solution in methanol. The asymmetric unit consists of a silver cation, [Ag(MET)₂]⁺, a tetrafluoridoborate anion, BF₄^–, and a solvent methanol molecule. The silver atom of [Ag(MET)₂]⁺ is coordinated by two MET ligands in a trans manner by their N³ nitrogen atoms, as illustrated in Fig. 1.

First, while the two MET ligands of both [Ag(MET)₂]BF₄ and [Ag(MET)₂]NO₃ are almost coplanar, the former compound has an anti-like geometry, and the latter has a syn-like arrangement. Thus, the C13—N11···N21—C23 torsion angle for [Ag(MET)₂]BF₄ is 160.8 (9)° [147.0 (8)° for the minor component of disorder], while the value for [Ag(MET)₂]NO₃ is 24.10° (Fun et al., 2008). These differences are illustrated in Fig. 2, which shows that the [Ag(MET)₂]⁺ unit of [Ag(MET)₂]BF₄ has an approximate inversion center at the Ag^I ion, whereas [Ag(MET)₂]NO₃ does not.

A second interesting difference is that the N11—Ag—N21 angle of 175.7 (5)° for [Ag(MET)₂]BF₄ is much closer to 180° than is the corresponding value for [Ag(MET)₂]NO₃ [165.34 (4)°; Fun et al., 2008). It is possible that this could be attributed to the tetrafluoridoborate ligand being considered a non-coordinating ion relative to nitrate, and this is reflected by the fact that [Ag(MET)₂]NO₃ exhibits Ag···O contacts of 2.63 and 2.67 Å, which are comparable to distances in other silver nitrate compounds (Wu et al., 2012).

Supramolecular features top

Database survey top

In addition to coordination to silver, metronidazole has also been shown to coordinate to other metals, and structurally characterized compounds have been reported for Co (Galván-Tejada et al., 2002), Cu (Galván-Tejada et al., 2002; Barba-Behrens et al., 1991; Athar et al., 2005; Ratajczak-Sitarz et al., 1998; Bharti et al., 2002), Zn (Galván-Tejada et al., 2002), Ru (Wu et al., 2003; Kennedy et al., 2006), Rh (Dyson et al., 1990; Nothenberg et al., 1994), Pd (Bharti et al., 2002; Debondt et al., 1994; Rochon et al., 1993) and Pt (Bharti et al., 2002; Bales et al., 1983). In these compounds, the coordination number of the central atom ranges from four for Cu, Zn, Pd and Pt to six for Ru and Rh.

Synthesis and crystallization top

Crystals of composition [Ag(MET)₂]BF₄.MeOH were obtained by combining AgBF₄ with MET in a 1:2 molar ratio in methanol and allowing the solution to evaporate slowly at room temperature.

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 2. Hydrogen atoms were refined using a riding-model approximation with C—H = 0.95–0.99 Å, O—H = 0.84 Å and U_iso(H) = 1.2U_eq(C,O). One of the MET ligands was refined as rotationally disordered with occupancies of 0.501 (17) and 0.499 (17) and the configurations were modeled using the SAME command in SHELXL2013 (Sheldrick, 2015). The tetrafluoridoborate counter-ion was also refined as disordered and was modeled with two site occupancies, 0.539 (19) and 0.461 (19).

Related literature top

For related literature, see: Athar et al. (2005); Bales et al. (1983); Barba-Behrens, Mutio-Rico, Joseph-Nathan & Contreras (1991); Bharti et al. (2002); Debondt et al. (1994); Dyson et al. (1990); Freeman et al. (1997); Fun et al. (2008); Galván-Tejada, Bernes, Castillo-Blum, Noth, Vicente & Barba-Behrens (2002); Kennedy et al. (2006); Lofmark et al. (2010); Miljkovic et al. (2014); Nothenberg et al. (1994); Ratajczak-Sitarz, Katrusiak, Wojakowska, Januszczyk, Krzyminiewski & Pietrzak (1998); Rochon et al. (1993); Samuelson (1999); Sheldrick (2008, 2015); Soares et al. (2012); Wu et al. (2003, 2012).

Computing details top

Data collection: APEX2 (Bruker, 2013); cell refinement: SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the cation of the title compound, with displacement ellipsoids drawn at the 30% probability level. The disorder is not shown.
	Fig. 2. Comparison of the [Ag(MET)₂]⁺ units in [Ag(MET)₂]BF₄ (top) and [Ag(MET)₂]NO₃ (bottom).
	Fig. 3. Part of a hydrogen-bonded chain along [001]. The disorder is not shown and hydrogen bonds are shown as dashed lines.

Bis[1-(2-hydroxyethyl)-2-methyl-5-nitro-1H-imidazole-κN³]silver(I) tetrafluoridoborate methanol monosolvate top

Crystal data top

[Ag(C₆H₉N₃O₃)₂](BF₄)·CH₄O	Z = 2
M_r = 569.04	F(000) = 572
Triclinic, P1	D_x = 1.797 Mg m⁻³
a = 9.2592 (10) Å	Mo Kα radiation, λ = 0.71073 Å
b = 10.5339 (10) Å	Cell parameters from 9065 reflections
c = 12.3995 (12) Å	θ = 2.3–32.9°
α = 106.940 (11)°	µ = 1.04 mm⁻¹
β = 92.788 (9)°	T = 130 K
γ = 112.439 (10)°	Block, colourless
V = 1051.7 (2) Å³	1.00 × 0.51 × 0.31 mm

Data collection top

Bruker APEXII CCD diffractometer	6107 reflections with I > 2σ(I)
ϕ and ω scans	R_int = 0.023
Absorption correction: multi-scan (SADABS; Bruker, 2013)	θ_max = 30.5°, θ_min = 1.8°
T_min = 0.551, T_max = 0.747	h = −13→13
17164 measured reflections	k = −15→15
6401 independent reflections	l = −17→17

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.028	w = 1/[σ²(F_o²) + (0.0161P)² + 1.0163P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.067	(Δ/σ)_max = 0.007
S = 1.12	Δρ_max = 1.00 e Å⁻³
6401 reflections	Δρ_min = −1.03 e Å⁻³
440 parameters	Extinction correction: SHELXL2013 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
144 restraints	Extinction coefficient: 0.0027 (4)

Crystal data top

[Ag(C₆H₉N₃O₃)₂](BF₄)·CH₄O	γ = 112.439 (10)°
M_r = 569.04	V = 1051.7 (2) Å³
Triclinic, P1	Z = 2
a = 9.2592 (10) Å	Mo Kα radiation
b = 10.5339 (10) Å	µ = 1.04 mm⁻¹
c = 12.3995 (12) Å	T = 130 K
α = 106.940 (11)°	1.00 × 0.51 × 0.31 mm
β = 92.788 (9)°

Data collection top

Bruker APEXII CCD diffractometer	6401 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2013)	6107 reflections with I > 2σ(I)
T_min = 0.551, T_max = 0.747	R_int = 0.023
17164 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.028	144 restraints
wR(F²) = 0.067	H-atom parameters constrained
S = 1.12	Δρ_max = 1.00 e Å⁻³
6401 reflections	Δρ_min = −1.03 e Å⁻³
440 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.

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
Ag	0.34662 (2)	0.82628 (2)	−0.00390 (2)	0.02854 (5)
N11	0.4710 (18)	0.786 (2)	0.1171 (7)	0.018 (2)	0.501 (17)
N12	0.5696 (15)	0.7754 (15)	0.2748 (8)	0.0211 (16)	0.501 (17)
N13	0.7178 (8)	0.6262 (7)	0.1956 (9)	0.0273 (14)	0.501 (17)
O11	0.3317 (11)	0.6459 (13)	0.4129 (9)	0.0404 (16)	0.501 (17)
H11A	0.2863	0.5926	0.3453	0.048*	0.501 (17)
O12	0.7349 (8)	0.5491 (6)	0.1064 (9)	0.0406 (13)	0.501 (17)
O13	0.7868 (7)	0.6518 (5)	0.2921 (10)	0.0368 (14)	0.501 (17)
C11	0.5471 (13)	0.6968 (12)	0.0851 (8)	0.0227 (15)	0.501 (17)
H11B	0.5535	0.6475	0.0092	0.027*	0.501 (17)
C12	0.6111 (12)	0.6925 (11)	0.1829 (8)	0.0197 (15)	0.501 (17)
C13	0.4855 (12)	0.8352 (11)	0.2301 (9)	0.0149 (15)	0.501 (17)
C14	0.3914 (18)	0.9109 (16)	0.2896 (10)	0.039 (4)	0.501 (17)
H14A	0.3477	0.9470	0.2375	0.047*	0.501 (17)
H14B	0.4599	0.9932	0.3572	0.047*	0.501 (17)
H14C	0.3043	0.8428	0.3136	0.047*	0.501 (17)
C15	0.5998 (12)	0.7981 (8)	0.3981 (7)	0.0282 (14)	0.501 (17)
H15A	0.5816	0.8841	0.4416	0.034*	0.501 (17)
H15B	0.7124	0.8190	0.4220	0.034*	0.501 (17)
C16	0.4946 (13)	0.6673 (12)	0.4271 (9)	0.0346 (19)	0.501 (17)
H16A	0.5035	0.5792	0.3772	0.042*	0.501 (17)
H16B	0.5316	0.6806	0.5076	0.042*	0.501 (17)
N11A	0.470 (2)	0.778 (2)	0.1207 (9)	0.028 (3)	0.499 (17)
N12A	0.5515 (16)	0.7755 (15)	0.2949 (8)	0.0179 (12)	0.499 (17)
N13A	0.7308 (8)	0.6471 (7)	0.2389 (8)	0.0224 (12)	0.499 (17)
O11A	0.2839 (10)	0.6195 (10)	0.4105 (9)	0.0349 (13)	0.499 (17)
H11C	0.2496	0.5780	0.3398	0.042*	0.499 (17)
O12A	0.7814 (9)	0.5918 (10)	0.1564 (8)	0.0368 (16)	0.499 (17)
O13A	0.7663 (7)	0.6551 (5)	0.3379 (7)	0.0314 (11)	0.499 (17)
C11A	0.5764 (13)	0.7137 (13)	0.1118 (8)	0.0212 (15)	0.499 (17)
H11D	0.6121	0.6788	0.0434	0.025*	0.499 (17)
C12A	0.6218 (12)	0.7076 (11)	0.2150 (7)	0.0170 (13)	0.499 (17)
C13A	0.4578 (12)	0.8126 (11)	0.2331 (8)	0.0140 (15)	0.499 (17)
C14A	0.3830 (17)	0.9117 (14)	0.2874 (9)	0.033 (4)	0.499 (17)
H14D	0.4602	1.0132	0.3073	0.039*	0.499 (17)
H14E	0.3490	0.8932	0.3571	0.039*	0.499 (17)
H14F	0.2906	0.8940	0.2338	0.039*	0.499 (17)
C15A	0.5567 (9)	0.7874 (8)	0.4170 (6)	0.0213 (11)	0.499 (17)
H15C	0.5264	0.8670	0.4571	0.026*	0.499 (17)
H15D	0.6671	0.8140	0.4521	0.026*	0.499 (17)
C16A	0.4482 (11)	0.6486 (10)	0.4345 (9)	0.0275 (16)	0.499 (17)
H16C	0.4661	0.5659	0.3840	0.033*	0.499 (17)
H16D	0.4758	0.6557	0.5148	0.033*	0.499 (17)
N21	0.20394 (19)	0.85591 (17)	−0.12498 (13)	0.0280 (3)
N22	0.06590 (19)	0.82730 (17)	−0.28744 (13)	0.0270 (3)
N23	−0.0132 (2)	1.0346 (2)	−0.2186 (2)	0.0433 (5)
O21	0.25596 (17)	0.86179 (17)	−0.45811 (12)	0.0340 (3)
H21A	0.2608	0.7842	−0.4975	0.051*
O22	−0.0234 (2)	1.1214 (2)	−0.1326 (2)	0.0737 (7)
O23	−0.0629 (3)	1.0220 (3)	−0.3151 (2)	0.0775 (8)
C21	0.1481 (2)	0.9618 (2)	−0.10391 (19)	0.0350 (4)
H21B	0.1652	1.0344	−0.0319	0.042*
C22	0.0644 (2)	0.94554 (19)	−0.20292 (19)	0.0306 (4)
C23	0.1525 (2)	0.77595 (19)	−0.23615 (14)	0.0250 (3)
C24	0.1834 (3)	0.6463 (2)	−0.29385 (16)	0.0349 (4)
H24A	0.2455	0.6290	−0.2379	0.042*
H24B	0.2429	0.6636	−0.3552	0.042*
H24C	0.0821	0.5608	−0.3265	0.042*
C25	−0.0068 (2)	0.7652 (3)	−0.40921 (17)	0.0375 (5)
H25A	−0.1117	0.7691	−0.4181	0.045*
H25B	−0.0236	0.6617	−0.4390	0.045*
C26	0.0986 (3)	0.8488 (3)	−0.4785 (2)	0.0456 (6)
H26A	0.0535	0.7976	−0.5612	0.055*
H26B	0.0997	0.9473	−0.4580	0.055*
C1	0.0949 (3)	0.4974 (3)	0.1155 (3)	0.0598 (7)
H1A	0.0573	0.5721	0.1520	0.072*
H1B	0.0045	0.4081	0.0682	0.072*
H1C	0.1706	0.5328	0.0672	0.072*
O1	0.1702 (3)	0.4678 (3)	0.20073 (19)	0.0787 (8)
H1	0.1856	0.3926	0.1706	0.094*
B1	0.3719 (2)	0.2457 (2)	0.19180 (16)	0.0263 (4)
F1	0.4132 (11)	0.1347 (10)	0.1303 (10)	0.0303 (13)	0.461 (19)
F2	0.2428 (8)	0.2394 (9)	0.1193 (6)	0.0313 (12)	0.461 (19)
F3	0.4916 (8)	0.3783 (7)	0.2162 (11)	0.0487 (18)	0.461 (19)
F4	0.3177 (7)	0.2190 (9)	0.2882 (5)	0.0395 (15)	0.461 (19)
F1A	0.4089 (12)	0.1282 (10)	0.1456 (10)	0.045 (2)	0.539 (19)
F2A	0.2240 (8)	0.2191 (10)	0.1397 (9)	0.0575 (19)	0.539 (19)
F3A	0.4837 (8)	0.3671 (8)	0.1725 (8)	0.0457 (13)	0.539 (19)
F4A	0.3783 (17)	0.2765 (12)	0.3073 (4)	0.080 (2)	0.539 (19)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ag	0.03598 (8)	0.02979 (7)	0.02076 (7)	0.01318 (6)	0.00356 (5)	0.01063 (5)
N11	0.020 (4)	0.016 (3)	0.025 (4)	0.013 (3)	0.012 (3)	0.008 (3)
N12	0.021 (3)	0.022 (2)	0.020 (3)	0.012 (2)	−0.003 (2)	0.002 (2)
N13	0.0202 (18)	0.018 (2)	0.045 (4)	0.0087 (15)	0.004 (3)	0.012 (2)
O11	0.040 (4)	0.050 (5)	0.0295 (18)	0.023 (3)	0.007 (3)	0.004 (3)
O12	0.040 (2)	0.034 (2)	0.055 (4)	0.0256 (18)	0.018 (2)	0.010 (2)
O13	0.0310 (19)	0.0325 (17)	0.051 (4)	0.0180 (14)	−0.004 (2)	0.015 (2)
C11	0.026 (4)	0.020 (3)	0.024 (3)	0.010 (3)	0.008 (3)	0.010 (3)
C12	0.019 (2)	0.015 (2)	0.024 (4)	0.0092 (18)	0.004 (3)	0.002 (3)
C13	0.007 (3)	0.009 (3)	0.025 (2)	−0.002 (3)	0.0010 (18)	0.0077 (17)
C14	0.054 (6)	0.047 (7)	0.028 (6)	0.033 (5)	−0.004 (4)	0.016 (5)
C15	0.035 (4)	0.025 (2)	0.024 (3)	0.018 (3)	−0.005 (2)	0.0024 (18)
C16	0.042 (5)	0.047 (4)	0.024 (3)	0.028 (4)	0.002 (3)	0.011 (2)
N11A	0.033 (5)	0.027 (6)	0.027 (5)	0.011 (4)	0.007 (3)	0.014 (4)
N12A	0.020 (2)	0.0159 (18)	0.019 (3)	0.0107 (16)	0.0043 (19)	0.004 (2)
N13A	0.019 (2)	0.020 (2)	0.032 (3)	0.0085 (16)	0.006 (2)	0.012 (2)
O11A	0.031 (3)	0.036 (3)	0.0304 (18)	0.008 (2)	0.010 (3)	0.0074 (17)
O12A	0.041 (3)	0.049 (3)	0.050 (3)	0.035 (3)	0.030 (3)	0.032 (3)
O13A	0.034 (2)	0.0296 (15)	0.033 (3)	0.0163 (13)	−0.0055 (17)	0.0111 (16)
C11A	0.025 (4)	0.024 (3)	0.021 (3)	0.015 (3)	0.009 (3)	0.010 (3)
C12A	0.0166 (19)	0.018 (3)	0.016 (3)	0.0060 (19)	0.001 (2)	0.007 (3)
C13A	0.006 (3)	0.008 (3)	0.022 (2)	−0.004 (3)	0.0011 (17)	0.0072 (17)
C14A	0.057 (6)	0.042 (6)	0.023 (5)	0.045 (6)	0.018 (4)	0.009 (4)
C15A	0.024 (3)	0.0262 (19)	0.015 (2)	0.012 (2)	0.0007 (16)	0.0060 (14)
C16A	0.037 (4)	0.025 (2)	0.022 (2)	0.012 (3)	0.009 (3)	0.0104 (16)
N21	0.0342 (8)	0.0243 (7)	0.0263 (7)	0.0143 (6)	0.0021 (6)	0.0072 (6)
N22	0.0333 (8)	0.0331 (8)	0.0280 (7)	0.0192 (6)	0.0108 (6)	0.0207 (6)
N23	0.0287 (8)	0.0314 (9)	0.0875 (16)	0.0166 (7)	0.0213 (9)	0.0373 (10)
O21	0.0335 (7)	0.0498 (8)	0.0312 (7)	0.0258 (6)	0.0119 (5)	0.0185 (6)
O22	0.0565 (11)	0.0321 (9)	0.1166 (19)	0.0296 (9)	−0.0178 (12)	−0.0075 (10)
O23	0.1030 (17)	0.131 (2)	0.0963 (16)	0.1008 (17)	0.0702 (14)	0.0957 (17)
C21	0.0299 (9)	0.0222 (8)	0.0454 (11)	0.0116 (7)	0.0000 (8)	0.0007 (7)
C22	0.0243 (8)	0.0201 (7)	0.0522 (11)	0.0102 (6)	0.0080 (7)	0.0173 (8)
C23	0.0348 (9)	0.0254 (8)	0.0225 (7)	0.0163 (7)	0.0063 (6)	0.0135 (6)
C24	0.0541 (12)	0.0358 (10)	0.0248 (8)	0.0301 (9)	0.0044 (8)	0.0089 (7)
C25	0.0317 (9)	0.0647 (14)	0.0302 (9)	0.0243 (9)	0.0083 (7)	0.0295 (9)
C26	0.0383 (11)	0.0888 (18)	0.0413 (11)	0.0383 (12)	0.0188 (9)	0.0481 (13)
C1	0.0312 (11)	0.0628 (17)	0.0691 (18)	0.0079 (11)	0.0019 (11)	0.0160 (14)
O1	0.0709 (13)	0.0848 (15)	0.0653 (13)	0.0613 (13)	−0.0276 (11)	−0.0290 (11)
B1	0.0270 (9)	0.0233 (8)	0.0235 (8)	0.0066 (7)	0.0073 (7)	0.0053 (7)
F1	0.037 (3)	0.028 (2)	0.031 (2)	0.0183 (18)	0.0130 (18)	0.0090 (19)
F2	0.037 (3)	0.029 (2)	0.0255 (16)	0.015 (2)	0.0004 (15)	0.0061 (13)
F3	0.0250 (17)	0.0217 (15)	0.083 (5)	0.0004 (12)	0.007 (3)	0.007 (3)
F4	0.039 (2)	0.055 (3)	0.0244 (17)	0.0204 (19)	0.0125 (14)	0.0110 (17)
F1A	0.070 (4)	0.031 (2)	0.039 (3)	0.025 (2)	0.010 (2)	0.0146 (19)
F2A	0.0192 (14)	0.047 (3)	0.074 (4)	0.0064 (16)	−0.001 (2)	−0.015 (3)
F3A	0.0341 (16)	0.0302 (19)	0.068 (3)	0.0038 (13)	0.006 (2)	0.023 (2)
F4A	0.125 (6)	0.081 (4)	0.0201 (16)	0.033 (5)	0.019 (2)	0.008 (2)

Geometric parameters (Å, º) top

Ag—N11	2.082 (15)	C15A—C16A	1.510 (9)
Ag—N21	2.1193 (15)	C15A—H15C	0.9900
Ag—N11A	2.163 (16)	C15A—H15D	0.9900
N11—C13	1.325 (9)	C16A—H16C	0.9900
N11—C11	1.365 (9)	C16A—H16D	0.9900
N12—C13	1.356 (9)	N21—C23	1.338 (2)
N12—C12	1.389 (9)	N21—C21	1.365 (2)
N12—C15	1.467 (8)	N22—C23	1.350 (2)
N13—O12	1.224 (6)	N22—C22	1.380 (3)
N13—O13	1.233 (6)	N22—C25	1.466 (3)
N13—C12	1.436 (8)	N23—O23	1.212 (3)
O11—C16	1.431 (9)	N23—O22	1.221 (3)
O11—H11A	0.8400	N23—C22	1.429 (2)
C11—C12	1.345 (9)	O21—C26	1.413 (2)
C11—H11B	0.9500	O21—H21A	0.8400
C13—C14	1.479 (9)	C21—C22	1.349 (3)
C14—H14A	0.9800	C21—H21B	0.9500
C14—H14B	0.9800	C23—C24	1.486 (2)
C14—H14C	0.9800	C24—H24A	0.9800
C15—C16	1.509 (9)	C24—H24B	0.9800
C15—H15A	0.9900	C24—H24C	0.9800
C15—H15B	0.9900	C25—C26	1.527 (3)
C16—H16A	0.9900	C25—H25A	0.9900
C16—H16B	0.9900	C25—H25B	0.9900
N11A—C13A	1.365 (8)	C26—H26A	0.9900
N11A—C11A	1.379 (9)	C26—H26B	0.9900
N12A—C13A	1.369 (9)	C1—O1	1.410 (4)
N12A—C12A	1.389 (9)	C1—H1A	0.9800
N12A—C15A	1.483 (8)	C1—H1B	0.9800
N13A—O13A	1.226 (5)	C1—H1C	0.9800
N13A—O12A	1.231 (6)	O1—H1	0.8400
N13A—C12A	1.445 (8)	B1—F3	1.346 (6)
O11A—C16A	1.430 (9)	B1—F4A	1.366 (4)
O11A—H11C	0.8400	B1—F2A	1.373 (6)
C11A—C12A	1.355 (9)	B1—F4	1.381 (4)
C11A—H11D	0.9500	B1—F1A	1.382 (7)
C13A—C14A	1.491 (9)	B1—F1	1.395 (6)
C14A—H14D	0.9800	B1—F3A	1.399 (5)
C14A—H14E	0.9800	B1—F2	1.428 (6)
C14A—H14F	0.9800

N11—Ag—N21	175.7 (5)	N12A—C15A—H15D	108.9
C13—N11—C11	111.5 (7)	C16A—C15A—H15D	108.9
C13—N11—Ag	128.4 (6)	H15C—C15A—H15D	107.7
C11—N11—Ag	121.4 (7)	O11A—C16A—C15A	112.9 (7)
C13—N12—C12	106.6 (7)	O11A—C16A—H16C	109.0
C13—N12—C15	122.1 (7)	C15A—C16A—H16C	109.0
C12—N12—C15	131.2 (7)	O11A—C16A—H16D	109.0
O12—N13—O13	125.0 (6)	C15A—C16A—H16D	109.0
O12—N13—C12	115.7 (5)	H16C—C16A—H16D	107.8
O13—N13—C12	119.2 (5)	C23—N21—C21	106.99 (16)
C16—O11—H11A	109.5	C23—N21—Ag	126.88 (12)
C12—C11—N11	105.1 (7)	C21—N21—Ag	126.14 (13)
C12—C11—H11B	127.5	C23—N22—C22	105.84 (15)
N11—C11—H11B	127.5	C23—N22—C25	124.53 (16)
C11—C12—N12	109.3 (7)	C22—N22—C25	129.62 (16)
C11—C12—N13	127.3 (6)	O23—N23—O22	123.6 (2)
N12—C12—N13	123.2 (6)	O23—N23—C22	119.0 (2)
N11—C13—N12	107.3 (7)	O22—N23—C22	117.3 (2)
N11—C13—C14	122.3 (8)	C26—O21—H21A	109.5
N12—C13—C14	127.2 (10)	C22—C21—N21	108.23 (17)
C13—C14—H14A	109.5	C22—C21—H21B	125.9
C13—C14—H14B	109.5	N21—C21—H21B	125.9
H14A—C14—H14B	109.5	C21—C22—N22	108.31 (15)
C13—C14—H14C	109.5	C21—C22—N23	126.3 (2)
H14A—C14—H14C	109.5	N22—C22—N23	125.40 (19)
H14B—C14—H14C	109.5	N21—C23—N22	110.63 (15)
N12—C15—C16	112.0 (8)	N21—C23—C24	124.38 (15)
N12—C15—H15A	109.2	N22—C23—C24	124.97 (16)
C16—C15—H15A	109.2	C23—C24—H24A	109.5
N12—C15—H15B	109.2	C23—C24—H24B	109.5
C16—C15—H15B	109.2	H24A—C24—H24B	109.5
H15A—C15—H15B	107.9	C23—C24—H24C	109.5
O11—C16—C15	112.1 (8)	H24A—C24—H24C	109.5
O11—C16—H16A	109.2	H24B—C24—H24C	109.5
C15—C16—H16A	109.2	N22—C25—C26	110.98 (19)
O11—C16—H16B	109.2	N22—C25—H25A	109.4
C15—C16—H16B	109.2	C26—C25—H25A	109.4
H16A—C16—H16B	107.9	N22—C25—H25B	109.4
C13A—N11A—C11A	103.4 (6)	C26—C25—H25B	109.4
C13A—N11A—Ag	122.6 (6)	H25A—C25—H25B	108.0
C11A—N11A—Ag	132.1 (8)	O21—C26—C25	111.84 (15)
C13A—N12A—C12A	104.6 (7)	O21—C26—H26A	109.2
C13A—N12A—C15A	127.3 (7)	C25—C26—H26A	109.2
C12A—N12A—C15A	127.5 (7)	O21—C26—H26B	109.2
O13A—N13A—O12A	125.3 (5)	C25—C26—H26B	109.2
O13A—N13A—C12A	118.6 (5)	H26A—C26—H26B	107.9
O12A—N13A—C12A	116.1 (5)	O1—C1—H1A	109.5
C16A—O11A—H11C	109.5	O1—C1—H1B	109.5
C12A—C11A—N11A	110.0 (10)	H1A—C1—H1B	109.5
C12A—C11A—H11D	124.5	O1—C1—H1C	109.5
N11A—C11A—H11D	124.5	H1A—C1—H1C	109.5
C11A—C12A—N12A	107.9 (7)	H1B—C1—H1C	109.5
C11A—C12A—N13A	125.8 (7)	C1—O1—H1	109.5
N12A—C12A—N13A	126.2 (7)	F4A—B1—F2A	110.2 (4)
N11A—C13A—N12A	112.9 (7)	F3—B1—F4	112.8 (4)
N11A—C13A—C14A	123.6 (8)	F4A—B1—F1A	110.7 (5)
N12A—C13A—C14A	122.9 (9)	F2A—B1—F1A	110.7 (5)
C13A—C14A—H14D	109.5	F3—B1—F1	111.9 (5)
C13A—C14A—H14E	109.5	F4—B1—F1	109.9 (6)
H14D—C14A—H14E	109.5	F4A—B1—F3A	108.5 (4)
C13A—C14A—H14F	109.5	F2A—B1—F3A	108.4 (5)
H14D—C14A—H14F	109.5	F1A—B1—F3A	108.4 (5)
H14E—C14A—H14F	109.5	F3—B1—F2	107.7 (5)
N12A—C15A—C16A	113.4 (8)	F4—B1—F2	107.7 (3)
N12A—C15A—H15C	108.9	F1—B1—F2	106.5 (5)
C16A—C15A—H15C	108.9

C13—N11—C11—C12	1.2 (14)	Ag—N11A—C13A—N12A	−178.7 (9)
Ag—N11—C11—C12	−179.8 (8)	C11A—N11A—C13A—C14A	166.5 (12)
N11—C11—C12—N12	1.2 (14)	Ag—N11A—C13A—C14A	−12 (2)
N11—C11—C12—N13	−173.5 (11)	C12A—N12A—C13A—N11A	−4.3 (15)
C13—N12—C12—C11	−3.1 (15)	C15A—N12A—C13A—N11A	−176.3 (12)
C15—N12—C12—C11	175.3 (13)	C12A—N12A—C13A—C14A	−168.1 (12)
C13—N12—C12—N13	171.8 (10)	C15A—N12A—C13A—C14A	20 (2)
C15—N12—C12—N13	−10 (2)	C13A—N12A—C15A—C16A	93.2 (15)
O12—N13—C12—C11	−10.3 (15)	C12A—N12A—C15A—C16A	−77.0 (15)
O13—N13—C12—C11	168.2 (11)	N12A—C15A—C16A—O11A	−71.9 (10)
O12—N13—C12—N12	175.6 (11)	C23—N21—C21—C22	−0.5 (2)
O13—N13—C12—N12	−5.8 (16)	Ag—N21—C21—C22	179.02 (13)
C11—N11—C13—N12	−3.2 (14)	N21—C21—C22—N22	0.6 (2)
Ag—N11—C13—N12	178.0 (9)	N21—C21—C22—N23	−179.57 (17)
C11—N11—C13—C14	−168.5 (12)	C23—N22—C22—C21	−0.4 (2)
Ag—N11—C13—C14	10 (2)	C25—N22—C22—C21	−179.75 (19)
C12—N12—C13—N11	3.8 (14)	C23—N22—C22—N23	179.73 (17)
C15—N12—C13—N11	−174.8 (11)	C25—N22—C22—N23	0.4 (3)
C12—N12—C13—C14	167.9 (13)	O23—N23—C22—C21	168.6 (2)
C15—N12—C13—C14	−11 (2)	O22—N23—C22—C21	−10.3 (3)
C13—N12—C15—C16	103.4 (13)	O23—N23—C22—N22	−11.6 (3)
C12—N12—C15—C16	−74.8 (16)	O22—N23—C22—N22	169.5 (2)
N12—C15—C16—O11	−68.9 (10)	C21—N21—C23—N22	0.2 (2)
C13A—N11A—C11A—C12A	1.5 (18)	Ag—N21—C23—N22	−179.28 (12)
Ag—N11A—C11A—C12A	−179.9 (13)	C21—N21—C23—C24	−178.24 (19)
N11A—C11A—C12A—N12A	−2.1 (15)	Ag—N21—C23—C24	2.2 (3)
N11A—C11A—C12A—N13A	−179.3 (10)	C22—N22—C23—N21	0.1 (2)
C13A—N12A—C12A—C11A	3.7 (15)	C25—N22—C23—N21	179.47 (17)
C15A—N12A—C12A—C11A	175.8 (12)	C22—N22—C23—C24	178.57 (18)
C13A—N12A—C12A—N13A	−179.0 (10)	C25—N22—C23—C24	−2.1 (3)
C15A—N12A—C12A—N13A	−7 (2)	C23—N22—C25—C26	−96.7 (2)
O13A—N13A—C12A—C11A	176.7 (10)	C22—N22—C25—C26	82.5 (2)
O12A—N13A—C12A—C11A	−2.9 (15)	N22—C25—C26—O21	52.0 (3)
O13A—N13A—C12A—N12A	−0.1 (16)	C13—N11—N21—C23	−160.8 (9)
O12A—N13A—C12A—N12A	−179.7 (11)	C13A—N11A—N21—C23	−148.6 (11)
C11A—N11A—C13A—N12A	0.8 (18)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···F2	0.84	1.84	2.673 (9)	173
O11—H11A···O1	0.84	1.86	2.697 (10)	175
O21—H21A···O11ⁱ	0.84	1.91	2.726 (11)	164
O21—H21A···O11Aⁱ	0.84	1.87	2.712 (11)	176

Symmetry code: (i) x, y, z−1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···F2	0.84	1.84	2.673 (9)	172.5
O11—H11A···O1	0.84	1.86	2.697 (10)	175.1
O21—H21A···O11ⁱ	0.84	1.91	2.726 (11)	163.5
O21—H21A···O11Aⁱ	0.84	1.87	2.712 (11)	175.8

Symmetry code: (i) x, y, z−1.

Experimental details

Crystal data
Chemical formula	[Ag(C₆H₉N₃O₃)₂](BF₄)·CH₄O
M_r	569.04
Crystal system, space group	Triclinic, P1
Temperature (K)	130
a, b, c (Å)	9.2592 (10), 10.5339 (10), 12.3995 (12)
α, β, γ (°)	106.940 (11), 92.788 (9), 112.439 (10)
V (Å³)	1051.7 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.04
Crystal size (mm)	1.00 × 0.51 × 0.31

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2013)
T_min, T_max	0.551, 0.747
No. of measured, independent and observed [I > 2σ(I)] reflections	17164, 6401, 6107
R_int	0.023
(sin θ/λ)_max (Å⁻¹)	0.714

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.028, 0.067, 1.12
No. of reflections	6401
No. of parameters	440
No. of restraints	144
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.00, −1.03

Computer programs: APEX2 (Bruker, 2013), SAINT (Bruker, 2013), SHELXS97 (Sheldrick, 2008), SHELXL2013 (Sheldrick, 2015), SHELXTL (Sheldrick, 2008).

Acknowledgements

RKU would like to thank Pace University for research support. Gerard Parkin (Columbia University) is thanked for helpful discussions.

References

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Volume 71| Part 3| March 2015| Pages 284-287

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