Crystal structures of morpholinium hydrogen bromanilate at 130, 145 and 180 K

Gotoh, K.; Tahara, Y.; Ishida, H.

doi:10.1107/S2056989015017272

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ISSN: 2056-9890

Volume 71| Part 10| October 2015| Pages 1226-1229

doi:10.1107/S2056989015017272

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Crystal structures of morpholinium hydrogen bromanilate at 130, 145 and 180 K

Kazuma Gotoh,^a Yuki Tahara ^a and Hiroyuki Ishida ^a ^*

^aDepartment of Chemistry, Faculty of Science, Okayama University, Okayama 700-8530, Japan
^*Correspondence e-mail: ishidah@cc.okayama-u.ac.jp

Edited by A. J. Lough, University of Toronto, Canada (Received 12 September 2015; accepted 16 September 2015; online 26 September 2015)

Crystal structures of the title compound (systematic name: morpholin-4-ium 2,5-dibromo-4-hydroxy-3,6-dioxocyclohexa-1,4-dien-1-olate), C₄H₁₀NO⁺·C₆HBr₂O₄⁻, were determined at three temperatures, viz. 130, 145 and 180 K. The asymmetric unit comprises one morpholinium cation and two halves of crystallographically independent bromanilate monoanions, which are located on inversion centres. The conformations of the two independent bromanilate anions are different from each other with respect to the O—H orientation. In the crystal, the two different anions are linked alternately into a chain along [211] through a short O—H⋯O hydrogen bond, in which the H atom is disordered over two positions. The refined site-occupancy ratios, which are almost constant in the temperature range studied, are 0.49 (3):0.51 (3), 0.52 (3):0.48 (3) and 0.50 (3):0.50 (3), respectively, at 130, 145 and 180 K, and no significant difference in the molecular geometry and the molecular packing is observed at the three temperatures. The morpholinium cation links adjacent chains of anions via N—H⋯O hydrogen bonds, forming a sheet structure parallel to (-111).

Keywords: crystal structure; bromanilic acid; morpholine; hydrogen-bonding; proton disorder.

CCDC references: 1424714; 1424713; 1424712

1. Chemical context

Anilic acid (2,5-dihydroxy-1,4-benzoquinone) derivatives, such as chloranilic acid (2,5-dichloro-3,6-dihydroxy-1,4-benzoqinone) and bromanilic acid (2,5-dibromo-3,6-dihydroxy-1,4-benzoqinone), appear particularly attractive as a versatile template for generating hydrogen-bonded self-assemblies with various organic bases (Zaman et al., 2001 ; Molčanov & Kojić-Prodić, 2010 ; Gotoh & Ishida, 2011 ; Thomas et al., 2013 ) and also as a model compound for investigating proton dynamics in hydrogen-bond systems (Ikeda et al., 2005 ; Seliger et al., 2009 ). Furthermore, salts and co-crystals of anilic acids with organic bases have attracted much interest with respect to organic ferroelectrics (Horiuchi et al., 2008 , 2009 , 2013 ).

In our previous study, we reported the crystal structure of morpholinium hydrogen chloranilate, C₄H₁₀NO⁺·C₆HCl₂O₄⁻, in which a short O—H⋯O hydrogen bond is formed between the chloranilate ions and the H atom in the hydrogen bond is disordered over two sites (Ishida & Kashino, 1999 ). The measurements of ³⁵Cl NQR (nuclear quadrupole resonance) for the compound in the temperature range 4–300 K showed an anomalous temperature dependence of the NQR frequencies, which cannot be explained by the conventional Bayer-type lattice motion: one of the two frequencies exhibits an anomalous increase with increasing temperature from 4.2 K while the other frequency shows a rather fast decrease with temperature. The anomalous behavior was ascribed to a drastic temperature variation of the disordered O—H⋯O hydrogen bond, as revealed by multi-temperature X-ray diffraction (Tobu et al., 2012 ). In the present study, we have undertaken the structural determination of morpholinium hydrogen bromanilate, C₄H₁₀NO⁺·C₆HBr₂O₄⁻, to extend the study of hydrogen-bonding in the amine-halohydroxybenzoquinone system.

2. Structural commentary

The title compound is isomorphous with morpholinium hydrogen chloranilate in the space group P $[\overline{1}]$ (Ishida & Kashino, 1999; Tobu et al., 2012) and has a quite similar molecular packing to the chloranilate. The asymmetric unit of the title compound comprises one morpholinium cation and two halves of crystallographically independent bromanilate monoanions, which are each located on an inversion centre (Fig. 1). The conformations of two bromanilate anions are different from each other with respect to the O—H orientation as shown schematically in Fig. 2.

Figure 1
A view of the molecular structure of the title compound at 180 K, showing the atom-numbering scheme. Displacement ellipsoids of non-H atoms are drawn at the 50% probability level and H atoms are drawn as circles of arbitrary size. The site-occupancy factors of the disordered H atom (H2 and H4) are approximately equal. The N—H⋯O and O—H⋯O hydrogen bonds are indicated by dashed lines. [Symmetry codes: (iii) −x, −y + 1, −z; (v) −x + 2, −y + 2, −z + 1.]

Figure 2
Two conformations (A and B forms) of bromanilic acid with respect to the O—H orientation.

In morpholinium hydrogen chloranilate, the bond distances of C3—O2 and C6—O4, which are involved in the disordered O—H⋯O hydrogen bond, showed slight but systematic decrease and increase, respectively, with temperature [C3—O2: from 1.2994 (10) Å at 114 K to 1.2951 (10) Å at 180 K; C6—O4: from 1.290 (10) Å at 114 K to 1.2946 (10) at 180 K], which corresponds to population changes of the two disordered proton sites in the hydrogen bond (Tobu et al., 2012). In the present compound, however, the C3—O2 and C6—O4 bond lengths are almost constant [C3—O2: 1.2953 (17), 1.2937 (17) and 1.2931 (17) Å at 130, 145 and 180 K; C6—O4: 1.3002 (18), 1.2997 (18) and 1.2997 (18) Å at 130, 145 and 180 K] and no significant difference in the molecular geometry is observed at the three temperatures.

3. Supramolecular features

In the crystal, the two independent bromanilate anions with different conformations are linked alternately by short O—H⋯O hydrogen bonds (Tables 1, 2 and 3), forming a chain along [211] (Fig. 3). The adjacent independent anions are almost perpendicular to each other, with dihedral angles of 86.57 (7)° (130 K), 86.65 (7)° (145 K) and 86.81 (7)° (180 K) between the benzoquinone rings. The morpholinium cation connects the anion chains through N—H⋯O hydrogen bonds and a weak C—H⋯O hydrogen bond into a sheet parallel to ( $[\overline{1}]$ 11) (Fig. 4). Between the chains, short Br⋯O and Br⋯C contacts [Br2⋯O1ⁱ: 3.1698 (13) Å (130 K), 3.1725 (13) Å (145 K) and 3.1763 (13) Å (180 K); Br2⋯C1ⁱ: 3.2673 (15) Å (130 K), 3.2716 (15) Å (145 K) and 3.2808 (15) Å (180 K); symmetry code: (i) x- 1, y − 1, z] are observed. A weak C—H⋯Br interaction is also observed between the sheets.

Table 1
Hydrogen-bond geometry (Å, °) at 130 K

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O4	0.88 (3)	2.03 (3)	2.886 (2)	166 (2)
N1—H1B⋯O1ⁱ	0.86 (3)	2.16 (3)	2.938 (2)	150 (2)
N1—H1B⋯O2ⁱⁱ	0.86 (3)	2.27 (3)	2.955 (2)	137 (2)
O2—H2⋯O4	0.81 (3)	1.77 (3)	2.5160 (16)	152 (4)
O2—H2⋯O3ⁱⁱⁱ	0.81 (3)	2.57 (3)	3.0613 (17)	120 (3)
O4—H4⋯O2	0.82 (3)	1.82 (4)	2.5160 (16)	143 (4)
C7—H7A⋯O4ⁱⁱ	0.99	2.53	3.391 (2)	145
C10—H10B⋯Br2^iv	0.99	2.90	3.8892 (17)	175
Symmetry codes: (i) x-1, y-1, z; (ii) -x+1, -y+1, -z+1; (iii) -x, -y+1, -z; (iv) -x, -y, -z.

Table 2
Hydrogen-bond geometry (Å, °) at 145 K

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O4	0.86 (3)	2.04 (3)	2.888 (2)	166 (2)
N1—H1B⋯O1ⁱ	0.85 (3)	2.17 (3)	2.938 (2)	151 (2)
N1—H1B⋯O2ⁱⁱ	0.85 (3)	2.29 (3)	2.959 (2)	136 (2)
O2—H2⋯O4	0.82 (3)	1.77 (3)	2.5174 (16)	153 (4)
O2—H2⋯O3ⁱⁱⁱ	0.82 (3)	2.58 (3)	3.0628 (17)	120 (3)
O4—H4⋯O2	0.82 (3)	1.79 (4)	2.5174 (16)	147 (4)
C7—H7A⋯O4ⁱⁱ	0.99	2.54	3.394 (2)	145
C10—H10B⋯Br2^iv	0.99	2.90	3.8905 (17)	175
Symmetry codes: (i) x-1, y-1, z; (ii) -x+1, -y+1, -z+1; (iii) -x, -y+1, -z; (iv) -x, -y, -z.

Table 3
Hydrogen-bond geometry (Å, °) at 180 K

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O4	0.89 (3)	2.02 (3)	2.890 (2)	167 (2)
N1—H1B⋯O1ⁱ	0.86 (3)	2.16 (3)	2.938 (2)	150 (2)
N1—H1B⋯O2ⁱⁱ	0.86 (3)	2.28 (3)	2.964 (2)	136 (2)
O2—H2⋯O4	0.82 (3)	1.79 (4)	2.5224 (16)	148 (5)
O2—H2⋯O3ⁱⁱⁱ	0.82 (3)	2.55 (4)	3.0678 (18)	122 (4)
O4—H4⋯O2	0.82 (3)	1.80 (4)	2.5224 (16)	147 (4)
C7—H7A⋯O4ⁱⁱ	0.99	2.55	3.402 (2)	145
C10—H10B⋯Br2^iv	0.99	2.91	3.8946 (17)	174
Symmetry codes: (i) x-1, y-1, z; (ii) -x+1, -y+1, -z+1; (iii) -x, -y+1, -z; (iv) -x, -y, -z.

Figure 3
A partial packing diagram of the title compound at 180 K, showing the hydrogen-bonded aggregate of morpholinium and hydrogen bromanilate ions. The N—H⋯O and O—H⋯O hydrogen bonds are indicated by dashed lines. [Symmetry codes: (i) x − 1, y − 1, z; (ii) −x + 1, −y + 1, −z + 1.]

Figure 4
A packing diagram of the title compound at 180 K, showing the sheet structure formed through N—H⋯O and O—H⋯O hydrogen bonds (dashed lines). For the morpholinium cations, only NH₂ groups are shown for clarity.

4. Database survey

Although a search of the Cambridge Structural Database (Version 5.36, last update February 2015; Groom & Allen, 2014 ) for organic salts and co-crystals with bromanilic acid gave 31 hits, no crystal structure including the A form (Fig. 2) was found.

5. Synthesis and crystallization

Single crystals of the title compound suitable for X-ray diffraction were prepared by slow evaporation from an acetonitrile solution (200 ml) of bromanilic acid (200 mg) with morpholine (60 mg) at room temperature.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 4. C-bound H atoms of the morpholinium cation were positioned geometrically with C—H = 0.99 Å and were refined as riding with U_iso(H) = 1.2U_eq(C). The N-bound H atom was located in a difference Fourier map and refined freely [refined N—H = 0.85 (3)–0.89 (3) Å]. Two disordered positions of the H atom in the O—H⋯O hydrogen bond were located in a difference Fourier map. Since site occupancy factors and isotropic displacement parameters are correlated and bonding effects also make the site-occupancy factors less reliable, the positional parameters and the occupancies of the H atom were refined, with U_iso(H) = 1.5U_eq(O), and with distance restraints of O—H = 0.84 (2) Å.

Table 4
Experimental details

	130 K	145 K	180 K
Crystal data
Chemical formula	C₄H₁₀NO⁺·C₆HBr₂O₄⁻	C₄H₁₀NO⁺·C₆HBr₂O₄⁻	C₄H₁₀NO⁺·C₆HBr₂O₄⁻
M_r	385.01	385.01	385.01
Crystal system, space group	Triclinic, P $[\overline{1}]$	Triclinic, P $[\overline{1}]$	Triclinic, P $[\overline{1}]$
a, b, c (Å)	8.62046 (19), 9.2129 (2), 9.4257 (2)	8.62293 (18), 9.21849 (19), 9.4354 (2)	8.62824 (17), 9.23087 (18), 9.46007 (19)
α, β, γ (°)	93.5208 (7), 112.9139 (7), 115.9757 (7)	93.5239 (7), 112.9190 (7), 115.9777 (7)	93.5321 (7), 112.9738 (7), 115.9508 (7)
V (Å³)	595.05 (3)	596.13 (3)	598.67 (3)
Z	2	2	2
Radiation type	Mo Kα	Mo Kα	Mo Kα
μ (mm⁻¹)	6.84	6.83	6.80
Crystal size (mm)	0.40 × 0.34 × 0.18	0.40 × 0.34 × 0.18	0.40 × 0.34 × 0.18

Data collection
Diffractometer	Rigaku R-AXIS RAPIDII	Rigaku R-AXIS RAPIDII	Rigaku R-AXIS RAPIDII
Absorption correction	Numerical (NUMABS; Higashi, 1999 )	Numerical (NUMABS; Higashi, 1999)	Numerical (NUMABS; Higashi, 1999)
T_min, T_max	0.096, 0.292	0.098, 0.292	0.098, 0.294
No. of measured, independent and observed [I > 2σ(I)] reflections	18162, 3468, 3183	18176, 3473, 3181	18199, 3487, 3188
R_int	0.026	0.028	0.026
(sin θ/λ)_max (Å⁻¹)	0.704	0.704	0.703

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.017, 0.046, 1.14	0.018, 0.046, 1.10	0.019, 0.048, 1.09
No. of reflections	3468	3473	3487
No. of parameters	178	178	178
No. of restraints	2	2	2
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement	H atoms treated by a mixture of independent and constrained refinement	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.50, −0.37	0.48, −0.44	0.59, −0.45
Computer programs: RAPID-AUTO (Rigaku, 2006 ), SIR92 (Altomare et al., 1994 ), SHELXL2014/7 (Sheldrick, 2015 ), ORTEP-3 for Windows (Farrugia, 2012 ), CrystalStructure (Rigaku, 2010 ) and PLATON (Spek, 2009 ).

Supporting information

CCDC references: 1424714; 1424713; 1424712

Crystal structure: contains datablocks General, 1, 2, 3. DOI: 10.1107/S2056989015017272/lh5788sup1.cif

Structure factors: contains datablock 1. DOI: 10.1107/S2056989015017272/lh57881sup2.hkl

Structure factors: contains datablock 2. DOI: 10.1107/S2056989015017272/lh57882sup3.hkl

Structure factors: contains datablock 3. DOI: 10.1107/S2056989015017272/lh57883sup4.hkl

Supporting information file. DOI: 10.1107/S2056989015017272/lh57881sup5.cml

checkCIF report

Chemical context top

Anilic acid (2,5-dihydroxy-1,4-benzoquinone) derivatives, such as chloranilic acid (2,5-dichloro-3,6-dihydroxy-1,4-benzoqinone) and bromanilic acid (2,5-dibromo-3,6-dihydroxy-1,4-benzoqinone), appear particularly attractive as a versatile template for generating hydrogen-bonded self-assemblies with various organic bases (Zaman et al., 2001; Molčanov & Kojić-Prodić, 2010; Gotoh & Ishida, 2011; Thomas et al., 2013) and also a model compound for investigating proton dynamics in hydrogen-bond systems (Ikeda et al., 2005; Seliger et al., 2009). Furthermore, salts and co-crystals of anilic acids with organic bases have attracted much interest with respect to organic ferroelectrics (Horiuchi et al., 2008, 2009, 2013).

In our previous study, we reported the crystal structure of morpholinium hydrogen chloranilate, C₄H₁₀NO⁺.C₆HCl₂O₄^-, in which a short O—H···O hydrogen bond is formed between the chloranilate ions and the H atom in the hydrogen bond is disordered over two sites (Ishida & Kashino, 1999). The measurements of ³⁵Cl NQR (nuclear quadrupole resonance) for the compound in the temperature range 4–300 K showed an anomalous temperature dependence of the NQR frequencies, which cannot be explained by the conventional Bayer-type lattice motion: one of the two frequencies exhibits an anomalous increase with increasing temperature from 4.2 K while the other frequency shows a rather fast decrease with temperature. The anomalous behavior was ascribed to a drastic temperature variation of the disordered O—H···O hydrogen bond, as revealed by multi-temperature X-ray diffraction (Tobu et al., 2012). In the present study, we have undertaken the structural determination morpholinium hydrogen bromanilate, C₄H₁₀NO⁺.C₆HBr₂O₄^-, to extend the study of hydrogen-bonding in the amine-halohydroxybenzoquinone system.

Structural commentary top

The title compound is isomorphous with morpholinium hydrogen chloranilate in the space group P1 (Ishida & Kashino, 1999; Tobu et al., 2012) and has a quite similar molecular packing to the chloranilate. The asymmetric unit of the title compound comprises one morpholinium cation and two halves of crystallographically independent bromanilate monoanions, which are each located on an inversion centre (Fig. 1). The conformations of two bromanilate anions are different from each other with respect to the O—H orientation as shown schematically in Fig. 2.

In morpholinium hydrogen chloranilate, the bond distances of C3—O2 and C6—O4, which are involved in the disordered O—H···O hydrogen bond, showed slight but systematic decrease and increase, respectively, with temperature [C3—O2: from 1.2994 (10) Å at 114 K to 1.2951 (10) Å at 180 K; C6—O4: from 1.290 (10) Å at 114 K to 1.2946 (10) at 180 K], which corresponds to population changes of the two disordered proton sites in the hydrogen bond (Tobu et al., 2012). In the present compound, however, the C3—O2 and C6—O4 bond lengths are almost constant [C3—O2: 1.2953 (17), 1.2937 (17) and 1.2931 (17) Å at 130, 145 and 180 K; C6—O4: 1.3002 (18), 1.2997 (18) and 1.2997 (18) Å at 130, 145 and 180 K] and no significant difference in the molecular geometry is observed at the three temperatures.

Supramolecular features top

In the crystal, the two independent bromanilate anions with different conformations are linked alternately by short O—H···O hydrogen bonds (Tables 1, 2 and 3), forming a chain along [211] (Fig. 3). The adjacent independent anions are almost perpendicular to each other, with dihedral angles of 86.57 (7)° (130 K), 86.65 (7)° (145 K) and 86.81 (7)° (180 K) between the benzoquinone rings. The morpholinium cation connects the anion chains through N—H···O hydrogen bonds and a weak C—H···O hydrogen bond into a sheet parallel to (111) (Fig. 4). Between the chains, short Br···O and Br···C contacts [Br2···O1ⁱ: 3.1698 (13) Å (130 K), 3.1725 (13) Å (145 K) and 3.1763 (13) Å (180 K); Br2···C1ⁱ: 3.2673 (15) Å (130 K), 3.2716 (15) Å (145 K) and 3.2808 (15) Å (180 K); symmetry code: (i) x- 1, y-1, z] are observed. A weak C—H···Br interaction is also observed between the sheets.

Database survey top

Although a search of the Cambridge Structural Database (Version 5.36, last update February 2015; Groom & Allen, 2014) for organic salts and co-crystals with bromanilic acid gave 31 hits, no crystal structure including the A form (Fig. 2) was found.

Synthesis and crystallization top

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 4. C-bound H atoms of the morpholinium cation were positioned geometrically with C—H = 0.99 Å and were refined as riding with U_iso(H) = 1.2U_eq(C). The N-bound H atom was located in a difference Fourier map and refined freely [refined N—H = 0.85 (3)–0.89 (3) Å]. Two disordered positions of the H atom in the O—H···O hydrogen bond were located in a difference Fourier map. Since site occupancy factors and isotropic displacement parameters are correlated and bonding effects also make the site-occupancy factors less reliable, the positional parameters and the occupancies of the H atom were refined, with U_iso(H) = 1.5U_eq(O), and with distance restraints of O—H = 0.84 (2) Å.

Related literature top

For related literature, see: Gotoh & Ishida (2011); Groom & Allen (2014); Horiuchi et al. (2008, 2009, 2013); Ikeda et al. (2005); Ishida & Kashino (1999): Molčanov et al. (2010); Seliger et al. (2009); Thomas et al. (2013); Tobu et al. (2012); Zaman et al. (2001).

Computing details top

For all compounds, data collection: RAPID-AUTO (Rigaku, 2006); cell refinement: RAPID-AUTO (Rigaku, 2006); data reduction: RAPID-AUTO (Rigaku, 2006); program(s) used to solve structure: SIR92 (Altomare et al., 1994). Program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015) for (1); SHELXL2014/7 (Sheldrick, 2015) for (2), (3). For all compounds, molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: CrystalStructure (Rigaku, 2010) and PLATON (Spek, 2009).

Figures top

	Fig. 1. A view of the molecular structure of the title compound at 180 K, showing the atom-numbering scheme. Displacement ellipsoids of non-H atoms are drawn at the 50% probability level and H atoms are drawn as circles of arbitrary size. The site-occupancy factors of the disordered H atom (H2 and H4) are approximately equal. The N—H···O and O—H···O hydrogen bonds are indicated by dashed lines. [Symmetry codes: (iii) -x, -y + 1, -z; (v) -x + 2, -y + 2, -z + 1.]
	Fig. 2. Two conformations (A and B forms) of bromanilic acid with respect to the O—H orientation.
	Fig. 3. A partial packing diagram of the title compound at 180 K, showing the hydrogen-bonded aggregate of morpholinium and hydrogen bromanilate ions. The N—H···O and O—H···O hydrogen bonds are indicated by dashed lines. [Symmetry codes: (i) x - 1, y - 1, z; (ii) -x + 1, -y + 1, -z + 1.]
	Fig. 4. A packing diagram of the title compound at 180 K, showing the sheet structure formed through N—H···O and O—H···O hydrogen bonds (dashed lines). For the morpholinium cations, only NH₂ groups are shown for clarity.

(1) Morpholin-4-ium 2,5-dibromo-4-hydroxy-3,6-dioxocyclohexa-1,4-dien-1-olate top

Crystal data top

C₄H₁₀NO⁺·C₆HBr₂O₄⁻	Z = 2
M_r = 385.01	F(000) = 376.00
Triclinic, P1	D_x = 2.149 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71075 Å
a = 8.62046 (19) Å	Cell parameters from 15996 reflections
b = 9.2129 (2) Å	θ = 3.0–30.1°
c = 9.4257 (2) Å	µ = 6.84 mm⁻¹
α = 93.5208 (7)°	T = 130 K
β = 112.9139 (7)°	Block, brown
γ = 115.9757 (7)°	0.40 × 0.34 × 0.18 mm
V = 595.05 (3) Å³

Data collection top

Rigaku R-AXIS RAPIDII diffractometer	3183 reflections with I > 2σ(I)
Detector resolution: 10.000 pixels mm^-1	R_int = 0.026
ω scans	θ_max = 30.0°, θ_min = 3.0°
Absorption correction: numerical (NUMABS; Higashi, 1999)	h = −12→12
T_min = 0.096, T_max = 0.292	k = −12→12
18162 measured reflections	l = −13→13
3468 independent reflections

Refinement top

Refinement on F²	2 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.017	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.046	w = 1/[σ²(F_o²) + (0.0195P)² + 0.3723P] where P = (F_o² + 2F_c²)/3
S = 1.14	(Δ/σ)_max = 0.002
3468 reflections	Δρ_max = 0.50 e Å⁻³
178 parameters	Δρ_min = −0.37 e Å⁻³

Crystal data top

C₄H₁₀NO⁺·C₆HBr₂O₄⁻	γ = 115.9757 (7)°
M_r = 385.01	V = 595.05 (3) Å³
Triclinic, P1	Z = 2
a = 8.62046 (19) Å	Mo Kα radiation
b = 9.2129 (2) Å	µ = 6.84 mm⁻¹
c = 9.4257 (2) Å	T = 130 K
α = 93.5208 (7)°	0.40 × 0.34 × 0.18 mm
β = 112.9139 (7)°

Data collection top

Rigaku R-AXIS RAPIDII diffractometer	3468 independent reflections
Absorption correction: numerical (NUMABS; Higashi, 1999)	3183 reflections with I > 2σ(I)
T_min = 0.096, T_max = 0.292	R_int = 0.026
18162 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.017	2 restraints
wR(F²) = 0.046	H atoms treated by a mixture of independent and constrained refinement
S = 1.14	Δρ_max = 0.50 e Å⁻³
3468 reflections	Δρ_min = −0.37 e Å⁻³
178 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. Reflections were merged by SHELXL according to the crystal class for the calculation of statistics and refinement.

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
Br1	0.75783 (2)	0.69637 (2)	0.16055 (2)	0.01583 (4)
Br2	−0.01546 (2)	0.16774 (2)	0.12333 (2)	0.01833 (4)
O1	1.18246 (16)	0.98222 (14)	0.33171 (13)	0.0166 (2)
O2	0.62026 (15)	0.76781 (13)	0.41041 (13)	0.0157 (2)
H2	0.548 (5)	0.699 (4)	0.323 (3)	0.023*	0.49 (3)
O3	−0.34652 (16)	0.22816 (14)	−0.08651 (15)	0.0209 (2)
O4	0.33771 (16)	0.50578 (13)	0.19213 (13)	0.0164 (2)
H4	0.427 (5)	0.603 (3)	0.226 (5)	0.025*	0.51 (3)
O5	0.82461 (16)	0.26388 (15)	0.42254 (14)	0.0201 (2)
N1	0.48737 (19)	0.29440 (17)	0.32853 (17)	0.0170 (2)
C1	1.0924 (2)	0.98617 (17)	0.40452 (17)	0.0123 (2)
C2	0.8902 (2)	0.86739 (17)	0.35299 (17)	0.0124 (2)
C3	0.7974 (2)	0.87220 (17)	0.44093 (17)	0.0126 (2)
C4	−0.1856 (2)	0.34950 (18)	−0.04567 (18)	0.0146 (3)
C5	−0.0041 (2)	0.35821 (17)	0.05629 (17)	0.0139 (3)
C6	0.1730 (2)	0.49677 (18)	0.10262 (17)	0.0145 (3)
C7	0.6812 (2)	0.42756 (19)	0.45862 (19)	0.0176 (3)
H7A	0.6639	0.4841	0.5393	0.021*
H7B	0.7493	0.5130	0.4132	0.021*
C8	0.8010 (2)	0.3481 (2)	0.53723 (19)	0.0188 (3)
H8A	0.9304	0.4362	0.6229	0.023*
H8B	0.7355	0.2669	0.5872	0.023*
C9	0.6388 (2)	0.1307 (2)	0.3035 (2)	0.0206 (3)
H9A	0.5750	0.0516	0.3557	0.025*
H9B	0.6567	0.0681	0.2277	0.025*
C10	0.5099 (2)	0.1976 (2)	0.21215 (19)	0.0196 (3)
H10A	0.5690	0.2717	0.1543	0.023*
H10B	0.3808	0.1032	0.1324	0.023*
H1A	0.423 (3)	0.342 (3)	0.277 (3)	0.023 (5)*
H1B	0.422 (3)	0.223 (3)	0.367 (3)	0.027 (6)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.01430 (7)	0.01537 (7)	0.01367 (7)	0.00509 (6)	0.00595 (5)	0.00068 (5)
Br2	0.01566 (8)	0.01334 (7)	0.02186 (8)	0.00595 (6)	0.00607 (6)	0.00785 (6)
O1	0.0150 (5)	0.0183 (5)	0.0179 (5)	0.0075 (4)	0.0102 (4)	0.0046 (4)
O2	0.0100 (5)	0.0154 (5)	0.0166 (5)	0.0031 (4)	0.0059 (4)	0.0020 (4)
O3	0.0129 (5)	0.0152 (5)	0.0277 (6)	0.0040 (4)	0.0065 (4)	0.0072 (4)
O4	0.0122 (5)	0.0129 (5)	0.0182 (5)	0.0048 (4)	0.0036 (4)	0.0037 (4)
O5	0.0151 (5)	0.0241 (6)	0.0217 (5)	0.0117 (5)	0.0073 (4)	0.0036 (4)
N1	0.0139 (6)	0.0193 (6)	0.0223 (6)	0.0101 (5)	0.0096 (5)	0.0109 (5)
C1	0.0117 (6)	0.0115 (6)	0.0141 (6)	0.0063 (5)	0.0056 (5)	0.0052 (5)
C2	0.0109 (6)	0.0119 (6)	0.0120 (6)	0.0047 (5)	0.0044 (5)	0.0022 (5)
C3	0.0106 (6)	0.0122 (6)	0.0145 (6)	0.0064 (5)	0.0045 (5)	0.0049 (5)
C4	0.0152 (7)	0.0125 (6)	0.0155 (6)	0.0060 (5)	0.0080 (5)	0.0028 (5)
C5	0.0147 (6)	0.0115 (6)	0.0153 (6)	0.0062 (5)	0.0070 (5)	0.0048 (5)
C6	0.0158 (7)	0.0129 (6)	0.0133 (6)	0.0058 (5)	0.0072 (5)	0.0023 (5)
C7	0.0180 (7)	0.0161 (7)	0.0198 (7)	0.0090 (6)	0.0093 (6)	0.0052 (6)
C8	0.0170 (7)	0.0231 (7)	0.0167 (7)	0.0118 (6)	0.0064 (6)	0.0052 (6)
C9	0.0189 (7)	0.0171 (7)	0.0232 (8)	0.0099 (6)	0.0068 (6)	0.0032 (6)
C10	0.0174 (7)	0.0182 (7)	0.0179 (7)	0.0086 (6)	0.0043 (6)	0.0019 (6)

Geometric parameters (Å, º) top

Br1—C2	1.8807 (14)	C1—C3ⁱ	1.5265 (19)
Br2—C5	1.8767 (14)	C2—C3	1.368 (2)
O1—C1	1.2295 (18)	C4—C5	1.445 (2)
O2—C3	1.2953 (17)	C4—C6ⁱⁱ	1.520 (2)
O2—H2	0.81 (3)	C5—C6	1.362 (2)
O3—C4	1.2229 (18)	C7—C8	1.511 (2)
O4—C6	1.3002 (18)	C7—H7A	0.9900
O4—H4	0.82 (3)	C7—H7B	0.9900
O5—C8	1.4212 (19)	C8—H8A	0.9900
O5—C9	1.428 (2)	C8—H8B	0.9900
N1—C7	1.492 (2)	C9—C10	1.509 (2)
N1—C10	1.494 (2)	C9—H9A	0.9900
N1—H1A	0.88 (3)	C9—H9B	0.9900
N1—H1B	0.86 (3)	C10—H10A	0.9900
C1—C2	1.4407 (19)	C10—H10B	0.9900

C3—O2—H2	118 (3)	C5—C6—C4ⁱⁱ	120.03 (13)
C6—O4—H4	111 (3)	N1—C7—C8	109.20 (12)
C8—O5—C9	109.71 (12)	N1—C7—H7A	109.8
C7—N1—C10	110.91 (12)	C8—C7—H7A	109.8
C7—N1—H1A	109.1 (14)	N1—C7—H7B	109.8
C10—N1—H1A	108.4 (14)	C8—C7—H7B	109.8
C7—N1—H1B	111.0 (15)	H7A—C7—H7B	108.3
C10—N1—H1B	107.1 (15)	O5—C8—C7	110.61 (13)
H1A—N1—H1B	110 (2)	O5—C8—H8A	109.5
O1—C1—C2	124.43 (13)	C7—C8—H8A	109.5
O1—C1—C3ⁱ	117.51 (13)	O5—C8—H8B	109.5
C2—C1—C3ⁱ	118.06 (12)	C7—C8—H8B	109.5
C3—C2—C1	122.59 (13)	H8A—C8—H8B	108.1
C3—C2—Br1	120.39 (11)	O5—C9—C10	111.23 (13)
C1—C2—Br1	116.98 (10)	O5—C9—H9A	109.4
O2—C3—C2	127.82 (13)	C10—C9—H9A	109.4
O2—C3—C1ⁱ	112.91 (12)	O5—C9—H9B	109.4
C2—C3—C1ⁱ	119.28 (12)	C10—C9—H9B	109.4
O3—C4—C5	124.23 (14)	H9A—C9—H9B	108.0
O3—C4—C6ⁱⁱ	118.64 (13)	N1—C10—C9	108.70 (13)
C5—C4—C6ⁱⁱ	117.13 (12)	N1—C10—H10A	109.9
C6—C5—C4	122.84 (13)	C9—C10—H10A	109.9
C6—C5—Br2	119.19 (11)	N1—C10—H10B	109.9
C4—C5—Br2	117.97 (10)	C9—C10—H10B	109.9
O4—C6—C5	123.65 (14)	H10A—C10—H10B	108.3
O4—C6—C4ⁱⁱ	116.29 (13)

O1—C1—C2—C3	177.29 (14)	C6ⁱⁱ—C4—C5—Br2	−178.24 (10)
C3ⁱ—C1—C2—C3	−3.3 (2)	C4—C5—C6—O4	−178.83 (14)
O1—C1—C2—Br1	−0.27 (19)	Br2—C5—C6—O4	−0.1 (2)
C3ⁱ—C1—C2—Br1	179.12 (9)	C4—C5—C6—C4ⁱⁱ	−0.5 (2)
C1—C2—C3—O2	−176.34 (14)	Br2—C5—C6—C4ⁱⁱ	178.22 (10)
Br1—C2—C3—O2	1.1 (2)	C10—N1—C7—C8	−54.86 (16)
C1—C2—C3—C1ⁱ	3.4 (2)	C9—O5—C8—C7	−62.32 (16)
Br1—C2—C3—C1ⁱ	−179.16 (9)	N1—C7—C8—O5	58.54 (17)
O3—C4—C5—C6	−178.49 (15)	C8—O5—C9—C10	62.50 (17)
C6ⁱⁱ—C4—C5—C6	0.5 (2)	C7—N1—C10—C9	54.40 (17)
O3—C4—C5—Br2	2.7 (2)	O5—C9—C10—N1	−58.02 (17)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O4	0.88 (3)	2.03 (3)	2.886 (2)	166 (2)
N1—H1B···O1ⁱⁱⁱ	0.86 (3)	2.16 (3)	2.938 (2)	150 (2)
N1—H1B···O2^iv	0.86 (3)	2.27 (3)	2.955 (2)	137 (2)
O2—H2···O4	0.81 (3)	1.77 (3)	2.5160 (16)	152 (4)
O2—H2···O3ⁱⁱ	0.81 (3)	2.57 (3)	3.0613 (17)	120 (3)
O4—H4···O2	0.82 (3)	1.82 (4)	2.5160 (16)	143 (4)
C7—H7A···O4^iv	0.99	2.53	3.391 (2)	145
C10—H10B···Br2^v	0.99	2.90	3.8892 (17)	175

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

(2) top

Crystal data top

C₄H₁₀NO⁺·C₆HBr₂O₄⁻	Z = 2
M_r = 385.01	F(000) = 376.00
Triclinic, P1	D_x = 2.145 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71075 Å
a = 8.62293 (18) Å	Cell parameters from 15916 reflections
b = 9.21849 (19) Å	θ = 3.0–30.1°
c = 9.4354 (2) Å	µ = 6.83 mm⁻¹
α = 93.5239 (7)°	T = 145 K
β = 112.9190 (7)°	Block, brown
γ = 115.9777 (7)°	0.40 × 0.34 × 0.18 mm
V = 596.13 (3) Å³

Data collection top

Rigaku R-AXIS RAPIDII diffractometer	3181 reflections with I > 2σ(I)
Detector resolution: 10.000 pixels mm^-1	R_int = 0.028
ω scans	θ_max = 30.0°, θ_min = 3.0°
Absorption correction: numerical (NUMABS; Higashi, 1999)	h = −12→12
T_min = 0.098, T_max = 0.292	k = −12→12
18176 measured reflections	l = −13→13
3473 independent reflections

Refinement top

Refinement on F²	2 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.018	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.046	w = 1/[σ²(F_o²) + (0.020P)² + 0.3611P] where P = (F_o² + 2F_c²)/3
S = 1.10	(Δ/σ)_max = 0.001
3473 reflections	Δρ_max = 0.48 e Å⁻³
178 parameters	Δρ_min = −0.44 e Å⁻³

Crystal data top

C₄H₁₀NO⁺·C₆HBr₂O₄⁻	γ = 115.9777 (7)°
M_r = 385.01	V = 596.13 (3) Å³
Triclinic, P1	Z = 2
a = 8.62293 (18) Å	Mo Kα radiation
b = 9.21849 (19) Å	µ = 6.83 mm⁻¹
c = 9.4354 (2) Å	T = 145 K
α = 93.5239 (7)°	0.40 × 0.34 × 0.18 mm
β = 112.9190 (7)°

Data collection top

Rigaku R-AXIS RAPIDII diffractometer	3473 independent reflections
Absorption correction: numerical (NUMABS; Higashi, 1999)	3181 reflections with I > 2σ(I)
T_min = 0.098, T_max = 0.292	R_int = 0.028
18176 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.018	2 restraints
wR(F²) = 0.046	H atoms treated by a mixture of independent and constrained refinement
S = 1.10	Δρ_max = 0.48 e Å⁻³
3473 reflections	Δρ_min = −0.44 e Å⁻³
178 parameters

Special details top

Refinement. Reflections were merged by SHELXL according to the crystal class for the calculation of statistics and refinement.

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
Br1	0.75812 (2)	0.69658 (2)	0.16087 (2)	0.01737 (4)
Br2	−0.01570 (2)	0.16791 (2)	0.12324 (2)	0.02003 (5)
O1	1.18243 (15)	0.98258 (14)	0.33190 (13)	0.0179 (2)
O2	0.62059 (15)	0.76777 (13)	0.41035 (13)	0.0172 (2)
H2	0.547 (5)	0.698 (4)	0.323 (3)	0.026*	0.52 (3)
O3	−0.34653 (16)	0.22841 (14)	−0.08661 (15)	0.0227 (2)
O4	0.33774 (15)	0.50586 (13)	0.19208 (13)	0.0175 (2)
H4	0.430 (5)	0.603 (3)	0.231 (5)	0.026*	0.48 (3)
O5	0.82422 (16)	0.26379 (15)	0.42261 (14)	0.0219 (2)
N1	0.48734 (19)	0.29444 (17)	0.32852 (17)	0.0183 (2)
C1	1.0922 (2)	0.98623 (17)	0.40454 (17)	0.0131 (2)
C2	0.8905 (2)	0.86761 (17)	0.35306 (17)	0.0138 (2)
C3	0.7975 (2)	0.87207 (17)	0.44087 (17)	0.0133 (2)
C4	−0.1856 (2)	0.34979 (18)	−0.04558 (17)	0.0156 (3)
C5	−0.0041 (2)	0.35843 (17)	0.05629 (17)	0.0149 (3)
C6	0.1731 (2)	0.49685 (18)	0.10257 (17)	0.0154 (3)
C7	0.6812 (2)	0.42735 (19)	0.45871 (19)	0.0191 (3)
H7A	0.6639	0.4839	0.5393	0.023*
H7B	0.7495	0.5128	0.4135	0.023*
C8	0.8006 (2)	0.3479 (2)	0.53709 (19)	0.0204 (3)
H8A	0.9300	0.4358	0.6228	0.025*
H8B	0.7349	0.2667	0.5868	0.025*
C9	0.6387 (2)	0.1307 (2)	0.3035 (2)	0.0227 (3)
H9A	0.5748	0.0515	0.3556	0.027*
H9B	0.6567	0.0683	0.2278	0.027*
C10	0.5097 (2)	0.1977 (2)	0.21235 (19)	0.0212 (3)
H10A	0.5687	0.2716	0.1545	0.025*
H10B	0.3806	0.1034	0.1327	0.025*
H1A	0.425 (3)	0.342 (3)	0.278 (3)	0.024 (5)*
H1B	0.422 (3)	0.224 (3)	0.365 (3)	0.030 (6)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.01574 (7)	0.01685 (7)	0.01495 (7)	0.00556 (6)	0.00658 (5)	0.00055 (5)
Br2	0.01706 (8)	0.01455 (7)	0.02405 (8)	0.00653 (6)	0.00668 (6)	0.00865 (6)
O1	0.0161 (5)	0.0199 (5)	0.0195 (5)	0.0081 (4)	0.0110 (4)	0.0050 (4)
O2	0.0108 (5)	0.0164 (5)	0.0184 (5)	0.0030 (4)	0.0064 (4)	0.0015 (4)
O3	0.0136 (5)	0.0158 (5)	0.0308 (6)	0.0039 (4)	0.0068 (5)	0.0081 (4)
O4	0.0128 (5)	0.0138 (5)	0.0195 (5)	0.0051 (4)	0.0035 (4)	0.0038 (4)
O5	0.0167 (5)	0.0258 (6)	0.0240 (6)	0.0130 (5)	0.0079 (4)	0.0038 (5)
N1	0.0146 (6)	0.0210 (6)	0.0244 (7)	0.0108 (5)	0.0105 (5)	0.0118 (5)
C1	0.0124 (6)	0.0127 (6)	0.0150 (6)	0.0069 (5)	0.0061 (5)	0.0057 (5)
C2	0.0124 (6)	0.0134 (6)	0.0134 (6)	0.0056 (5)	0.0051 (5)	0.0025 (5)
C3	0.0113 (6)	0.0125 (6)	0.0151 (6)	0.0064 (5)	0.0046 (5)	0.0049 (5)
C4	0.0168 (7)	0.0131 (6)	0.0161 (6)	0.0063 (5)	0.0083 (5)	0.0028 (5)
C5	0.0156 (6)	0.0123 (6)	0.0161 (6)	0.0067 (5)	0.0071 (5)	0.0047 (5)
C6	0.0166 (7)	0.0139 (6)	0.0139 (6)	0.0060 (5)	0.0076 (5)	0.0021 (5)
C7	0.0195 (7)	0.0172 (7)	0.0223 (7)	0.0095 (6)	0.0107 (6)	0.0059 (6)
C8	0.0187 (7)	0.0251 (7)	0.0177 (7)	0.0129 (6)	0.0066 (6)	0.0051 (6)
C9	0.0209 (7)	0.0185 (7)	0.0255 (8)	0.0108 (6)	0.0073 (6)	0.0028 (6)
C10	0.0185 (7)	0.0206 (7)	0.0189 (7)	0.0093 (6)	0.0047 (6)	0.0022 (6)

Geometric parameters (Å, º) top

Br1—C2	1.8807 (14)	C1—C3ⁱ	1.5282 (19)
Br2—C5	1.8775 (14)	C2—C3	1.3684 (19)
O1—C1	1.2298 (17)	C4—C5	1.446 (2)
O2—C3	1.2937 (17)	C4—C6ⁱⁱ	1.518 (2)
O2—H2	0.82 (3)	C5—C6	1.363 (2)
O3—C4	1.2231 (18)	C7—C8	1.509 (2)
O4—C6	1.2997 (18)	C7—H7A	0.9900
O4—H4	0.82 (3)	C7—H7B	0.9900
O5—C8	1.4201 (19)	C8—H8A	0.9900
O5—C9	1.428 (2)	C8—H8B	0.9900
N1—C7	1.492 (2)	C9—C10	1.510 (2)
N1—C10	1.493 (2)	C9—H9A	0.9900
N1—H1A	0.86 (3)	C9—H9B	0.9900
N1—H1B	0.85 (3)	C10—H10A	0.9900
C1—C2	1.4377 (19)	C10—H10B	0.9900

C3—O2—H2	118 (3)	C5—C6—C4ⁱⁱ	119.95 (13)
C6—O4—H4	113 (3)	N1—C7—C8	109.23 (12)
C8—O5—C9	109.77 (12)	N1—C7—H7A	109.8
C7—N1—C10	110.93 (12)	C8—C7—H7A	109.8
C7—N1—H1A	108.5 (14)	N1—C7—H7B	109.8
C10—N1—H1A	108.6 (14)	C8—C7—H7B	109.8
C7—N1—H1B	111.9 (16)	H7A—C7—H7B	108.3
C10—N1—H1B	106.6 (15)	O5—C8—C7	110.62 (13)
H1A—N1—H1B	110 (2)	O5—C8—H8A	109.5
O1—C1—C2	124.48 (13)	C7—C8—H8A	109.5
O1—C1—C3ⁱ	117.39 (12)	O5—C8—H8B	109.5
C2—C1—C3ⁱ	118.13 (12)	C7—C8—H8B	109.5
C3—C2—C1	122.62 (13)	H8A—C8—H8B	108.1
C3—C2—Br1	120.30 (11)	O5—C9—C10	111.19 (13)
C1—C2—Br1	117.03 (10)	O5—C9—H9A	109.4
O2—C3—C2	127.87 (13)	C10—C9—H9A	109.4
O2—C3—C1ⁱ	112.96 (12)	O5—C9—H9B	109.4
C2—C3—C1ⁱ	119.17 (12)	C10—C9—H9B	109.4
O3—C4—C5	124.23 (13)	H9A—C9—H9B	108.0
O3—C4—C6ⁱⁱ	118.58 (13)	N1—C10—C9	108.74 (13)
C5—C4—C6ⁱⁱ	117.19 (12)	N1—C10—H10A	109.9
C6—C5—C4	122.86 (13)	C9—C10—H10A	109.9
C6—C5—Br2	119.20 (11)	N1—C10—H10B	109.9
C4—C5—Br2	117.92 (10)	C9—C10—H10B	109.9
O4—C6—C5	123.68 (13)	H10A—C10—H10B	108.3
O4—C6—C4ⁱⁱ	116.36 (12)

O1—C1—C2—C3	177.25 (14)	C6ⁱⁱ—C4—C5—Br2	−178.23 (10)
C3ⁱ—C1—C2—C3	−3.4 (2)	C4—C5—C6—O4	−178.92 (13)
O1—C1—C2—Br1	−0.21 (19)	Br2—C5—C6—O4	−0.2 (2)
C3ⁱ—C1—C2—Br1	179.18 (9)	C4—C5—C6—C4ⁱⁱ	−0.6 (2)
C1—C2—C3—O2	−176.36 (13)	Br2—C5—C6—C4ⁱⁱ	178.19 (10)
Br1—C2—C3—O2	1.0 (2)	C10—N1—C7—C8	−54.81 (16)
C1—C2—C3—C1ⁱ	3.4 (2)	C9—O5—C8—C7	−62.38 (16)
Br1—C2—C3—C1ⁱ	−179.22 (9)	N1—C7—C8—O5	58.53 (17)
O3—C4—C5—C6	−178.65 (15)	C8—O5—C9—C10	62.43 (17)
C6ⁱⁱ—C4—C5—C6	0.5 (2)	C7—N1—C10—C9	54.27 (17)
O3—C4—C5—Br2	2.6 (2)	O5—C9—C10—N1	−57.89 (18)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O4	0.86 (3)	2.04 (3)	2.888 (2)	166 (2)
N1—H1B···O1ⁱⁱⁱ	0.85 (3)	2.17 (3)	2.938 (2)	151 (2)
N1—H1B···O2^iv	0.85 (3)	2.29 (3)	2.959 (2)	136 (2)
O2—H2···O4	0.82 (3)	1.77 (3)	2.5174 (16)	153 (4)
O2—H2···O3ⁱⁱ	0.82 (3)	2.58 (3)	3.0628 (17)	120 (3)
O4—H4···O2	0.82 (3)	1.79 (4)	2.5174 (16)	147 (4)
C7—H7A···O4^iv	0.99	2.54	3.394 (2)	145
C10—H10B···Br2^v	0.99	2.90	3.8905 (17)	175

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

(3) top

Crystal data top

C₄H₁₀NO⁺·C₆HBr₂O₄⁻	Z = 2
M_r = 385.01	F(000) = 376.00
Triclinic, P1	D_x = 2.136 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71075 Å
a = 8.62824 (17) Å	Cell parameters from 15838 reflections
b = 9.23087 (18) Å	θ = 3.0–30.1°
c = 9.46007 (19) Å	µ = 6.80 mm⁻¹
α = 93.5321 (7)°	T = 180 K
β = 112.9738 (7)°	Block, brown
γ = 115.9508 (7)°	0.40 × 0.34 × 0.18 mm
V = 598.67 (3) Å³

Data collection top

Rigaku R-AXIS RAPIDII diffractometer	3188 reflections with I > 2σ(I)
Detector resolution: 10.000 pixels mm^-1	R_int = 0.026
ω scans	θ_max = 30.0°
Absorption correction: numerical (NUMABS; Higashi, 1999)	h = −12→12
T_min = 0.098, T_max = 0.294	k = −12→12
18199 measured reflections	l = −13→13
3487 independent reflections

Refinement top

Refinement on F²	2 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.019	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.048	w = 1/[σ²(F_o²) + (0.0216P)² + 0.3489P] where P = (F_o² + 2F_c²)/3
S = 1.09	(Δ/σ)_max = 0.001
3487 reflections	Δρ_max = 0.59 e Å⁻³
178 parameters	Δρ_min = −0.45 e Å⁻³

Crystal data top

C₄H₁₀NO⁺·C₆HBr₂O₄⁻	γ = 115.9508 (7)°
M_r = 385.01	V = 598.67 (3) Å³
Triclinic, P1	Z = 2
a = 8.62824 (17) Å	Mo Kα radiation
b = 9.23087 (18) Å	µ = 6.80 mm⁻¹
c = 9.46007 (19) Å	T = 180 K
α = 93.5321 (7)°	0.40 × 0.34 × 0.18 mm
β = 112.9738 (7)°

Data collection top

Rigaku R-AXIS RAPIDII diffractometer	3487 independent reflections
Absorption correction: numerical (NUMABS; Higashi, 1999)	3188 reflections with I > 2σ(I)
T_min = 0.098, T_max = 0.294	R_int = 0.026
18199 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.019	2 restraints
wR(F²) = 0.048	H atoms treated by a mixture of independent and constrained refinement
S = 1.09	Δρ_max = 0.59 e Å⁻³
3487 reflections	Δρ_min = −0.45 e Å⁻³
178 parameters

Special details top

Refinement. Reflections were merged by SHELXL according to the crystal class for the calculation of statistics and refinement.

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
Br1	0.75874 (2)	0.69709 (2)	0.16160 (2)	0.02126 (5)
Br2	−0.01629 (2)	0.16834 (2)	0.12298 (2)	0.02440 (5)
O1	1.18225 (16)	0.98340 (14)	0.33207 (13)	0.0212 (2)
O2	0.62107 (15)	0.76749 (14)	0.41043 (13)	0.0205 (2)
H2	0.550 (6)	0.702 (5)	0.321 (3)	0.031*	0.50 (3)
O3	−0.34638 (16)	0.22923 (14)	−0.08655 (16)	0.0275 (2)
O4	0.33726 (16)	0.50565 (14)	0.19202 (13)	0.0209 (2)
H4	0.426 (5)	0.604 (3)	0.231 (5)	0.031*	0.50 (3)
O5	0.82325 (17)	0.26349 (16)	0.42251 (15)	0.0266 (2)
N1	0.48719 (19)	0.29464 (18)	0.32897 (17)	0.0216 (3)
C1	1.0921 (2)	0.98669 (17)	0.40464 (17)	0.0155 (2)
C2	0.8904 (2)	0.86771 (17)	0.35338 (17)	0.0158 (2)
C3	0.7977 (2)	0.87190 (17)	0.44099 (17)	0.0157 (2)
C4	−0.1853 (2)	0.35010 (18)	−0.04556 (18)	0.0185 (3)
C5	−0.0045 (2)	0.35849 (17)	0.05607 (17)	0.0175 (3)
C6	0.1728 (2)	0.49667 (18)	0.10245 (17)	0.0180 (3)
C7	0.6809 (2)	0.42714 (19)	0.4585 (2)	0.0227 (3)
H7A	0.6639	0.4840	0.5389	0.027*
H7B	0.7492	0.5122	0.4133	0.027*
C8	0.7997 (2)	0.3474 (2)	0.53683 (19)	0.0250 (3)
H8A	0.9291	0.4350	0.6226	0.030*
H8B	0.7337	0.2662	0.5861	0.030*
C9	0.6381 (2)	0.1310 (2)	0.3036 (2)	0.0272 (3)
H9A	0.5742	0.0517	0.3552	0.033*
H9B	0.6562	0.0690	0.2279	0.033*
C10	0.5094 (2)	0.1980 (2)	0.21303 (19)	0.0252 (3)
H10A	0.5683	0.2719	0.1554	0.030*
H10B	0.3803	0.1040	0.1335	0.030*
H1A	0.424 (3)	0.344 (3)	0.277 (2)	0.025 (5)*
H1B	0.422 (3)	0.223 (3)	0.367 (3)	0.026 (5)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.01905 (8)	0.02063 (8)	0.01805 (7)	0.00654 (6)	0.00783 (6)	0.00043 (5)
Br2	0.02061 (8)	0.01771 (7)	0.02936 (9)	0.00800 (6)	0.00791 (6)	0.01079 (6)
O1	0.0192 (5)	0.0234 (5)	0.0227 (5)	0.0093 (4)	0.0131 (4)	0.0057 (4)
O2	0.0128 (5)	0.0201 (5)	0.0215 (5)	0.0035 (4)	0.0076 (4)	0.0019 (4)
O3	0.0161 (5)	0.0194 (5)	0.0374 (7)	0.0049 (4)	0.0080 (5)	0.0101 (5)
O4	0.0151 (5)	0.0166 (5)	0.0230 (5)	0.0061 (4)	0.0039 (4)	0.0046 (4)
O5	0.0192 (5)	0.0314 (6)	0.0295 (6)	0.0151 (5)	0.0094 (5)	0.0045 (5)
N1	0.0171 (6)	0.0245 (6)	0.0290 (7)	0.0129 (5)	0.0123 (5)	0.0141 (6)
C1	0.0148 (6)	0.0147 (6)	0.0180 (6)	0.0076 (5)	0.0079 (5)	0.0069 (5)
C2	0.0141 (6)	0.0144 (6)	0.0159 (6)	0.0057 (5)	0.0062 (5)	0.0027 (5)
C3	0.0133 (6)	0.0155 (6)	0.0180 (6)	0.0076 (5)	0.0064 (5)	0.0061 (5)
C4	0.0181 (7)	0.0155 (6)	0.0197 (6)	0.0065 (5)	0.0092 (5)	0.0034 (5)
C5	0.0175 (6)	0.0141 (6)	0.0192 (6)	0.0073 (5)	0.0078 (5)	0.0053 (5)
C6	0.0188 (7)	0.0164 (6)	0.0166 (6)	0.0071 (5)	0.0086 (5)	0.0030 (5)
C7	0.0231 (7)	0.0208 (7)	0.0259 (7)	0.0111 (6)	0.0129 (6)	0.0066 (6)
C8	0.0219 (7)	0.0308 (8)	0.0218 (7)	0.0150 (7)	0.0080 (6)	0.0061 (6)
C9	0.0250 (8)	0.0217 (7)	0.0317 (8)	0.0129 (7)	0.0095 (7)	0.0036 (6)
C10	0.0218 (7)	0.0243 (7)	0.0220 (7)	0.0108 (6)	0.0051 (6)	0.0025 (6)

Geometric parameters (Å, º) top

Br1—C2	1.8803 (14)	C1—C3ⁱ	1.5283 (19)
Br2—C5	1.8769 (14)	C2—C3	1.367 (2)
O1—C1	1.2299 (17)	C4—C5	1.442 (2)
O2—C3	1.2931 (17)	C4—C6ⁱⁱ	1.519 (2)
O2—H2	0.82 (3)	C5—C6	1.363 (2)
O3—C4	1.2229 (18)	C7—C8	1.509 (2)
O4—C6	1.2997 (18)	C7—H7A	0.9900
O4—H4	0.82 (3)	C7—H7B	0.9900
O5—C8	1.420 (2)	C8—H8A	0.9900
O5—C9	1.425 (2)	C8—H8B	0.9900
N1—C7	1.490 (2)	C9—C10	1.508 (2)
N1—C10	1.493 (2)	C9—H9A	0.9900
N1—H1A	0.89 (3)	C9—H9B	0.9900
N1—H1B	0.86 (3)	C10—H10A	0.9900
C1—C2	1.4394 (19)	C10—H10B	0.9900

C3—O2—H2	117 (3)	C5—C6—C4ⁱⁱ	119.94 (13)
C6—O4—H4	111 (3)	N1—C7—C8	109.14 (13)
C8—O5—C9	109.83 (12)	N1—C7—H7A	109.9
C7—N1—C10	110.85 (12)	C8—C7—H7A	109.9
C7—N1—H1A	108.4 (14)	N1—C7—H7B	109.9
C10—N1—H1A	108.2 (14)	C8—C7—H7B	109.9
C7—N1—H1B	111.2 (14)	H7A—C7—H7B	108.3
C10—N1—H1B	106.4 (14)	O5—C8—C7	110.51 (13)
H1A—N1—H1B	112 (2)	O5—C8—H8A	109.5
O1—C1—C2	124.51 (13)	C7—C8—H8A	109.5
O1—C1—C3ⁱ	117.41 (12)	O5—C8—H8B	109.5
C2—C1—C3ⁱ	118.08 (12)	C7—C8—H8B	109.5
C3—C2—C1	122.63 (13)	H8A—C8—H8B	108.1
C3—C2—Br1	120.43 (11)	O5—C9—C10	111.18 (13)
C1—C2—Br1	116.90 (10)	O5—C9—H9A	109.4
O2—C3—C2	127.81 (13)	C10—C9—H9A	109.4
O2—C3—C1ⁱ	112.98 (12)	O5—C9—H9B	109.4
C2—C3—C1ⁱ	119.21 (12)	C10—C9—H9B	109.4
O3—C4—C5	124.27 (14)	H9A—C9—H9B	108.0
O3—C4—C6ⁱⁱ	118.48 (14)	N1—C10—C9	108.84 (13)
C5—C4—C6ⁱⁱ	117.24 (12)	N1—C10—H10A	109.9
C6—C5—C4	122.82 (13)	C9—C10—H10A	109.9
C6—C5—Br2	119.20 (11)	N1—C10—H10B	109.9
C4—C5—Br2	117.98 (10)	C9—C10—H10B	109.9
O4—C6—C5	123.69 (14)	H10A—C10—H10B	108.3
O4—C6—C4ⁱⁱ	116.35 (13)

O1—C1—C2—C3	177.30 (14)	C6ⁱⁱ—C4—C5—Br2	−178.27 (10)
C3ⁱ—C1—C2—C3	−3.3 (2)	C4—C5—C6—O4	−178.95 (14)
O1—C1—C2—Br1	−0.20 (19)	Br2—C5—C6—O4	−0.2 (2)
C3ⁱ—C1—C2—Br1	179.24 (9)	C4—C5—C6—C4ⁱⁱ	−0.5 (2)
C1—C2—C3—O2	−176.48 (14)	Br2—C5—C6—C4ⁱⁱ	178.25 (10)
Br1—C2—C3—O2	0.9 (2)	C10—N1—C7—C8	−55.03 (17)
C1—C2—C3—C1ⁱ	3.3 (2)	C9—O5—C8—C7	−62.46 (17)
Br1—C2—C3—C1ⁱ	−179.29 (9)	N1—C7—C8—O5	58.77 (17)
O3—C4—C5—C6	−178.51 (15)	C8—O5—C9—C10	62.31 (18)
C6ⁱⁱ—C4—C5—C6	0.5 (2)	C7—N1—C10—C9	54.35 (17)
O3—C4—C5—Br2	2.7 (2)	O5—C9—C10—N1	−57.76 (19)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O4	0.89 (3)	2.02 (3)	2.890 (2)	167 (2)
N1—H1B···O1ⁱⁱⁱ	0.86 (3)	2.16 (3)	2.938 (2)	150 (2)
N1—H1B···O2^iv	0.86 (3)	2.28 (3)	2.964 (2)	136 (2)
O2—H2···O4	0.82 (3)	1.79 (4)	2.5224 (16)	148 (5)
O2—H2···O3ⁱⁱ	0.82 (3)	2.55 (4)	3.0678 (18)	122 (4)
O4—H4···O2	0.82 (3)	1.80 (4)	2.5224 (16)	147 (4)
C7—H7A···O4^iv	0.99	2.55	3.402 (2)	145
C10—H10B···Br2^v	0.99	2.91	3.8946 (17)	174

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

Hydrogen-bond geometry (Å, º) for (1) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O4	0.88 (3)	2.03 (3)	2.886 (2)	166 (2)
N1—H1B···O1ⁱ	0.86 (3)	2.16 (3)	2.938 (2)	150 (2)
N1—H1B···O2ⁱⁱ	0.86 (3)	2.27 (3)	2.955 (2)	137 (2)
O2—H2···O4	0.81 (3)	1.77 (3)	2.5160 (16)	152 (4)
O2—H2···O3ⁱⁱⁱ	0.81 (3)	2.57 (3)	3.0613 (17)	120 (3)
O4—H4···O2	0.82 (3)	1.82 (4)	2.5160 (16)	143 (4)
C7—H7A···O4ⁱⁱ	0.99	2.53	3.391 (2)	145
C10—H10B···Br2^iv	0.99	2.90	3.8892 (17)	175

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

Hydrogen-bond geometry (Å, º) for (2) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O4	0.86 (3)	2.04 (3)	2.888 (2)	166 (2)
N1—H1B···O1ⁱ	0.85 (3)	2.17 (3)	2.938 (2)	151 (2)
N1—H1B···O2ⁱⁱ	0.85 (3)	2.29 (3)	2.959 (2)	136 (2)
O2—H2···O4	0.82 (3)	1.77 (3)	2.5174 (16)	153 (4)
O2—H2···O3ⁱⁱⁱ	0.82 (3)	2.58 (3)	3.0628 (17)	120 (3)
O4—H4···O2	0.82 (3)	1.79 (4)	2.5174 (16)	147 (4)
C7—H7A···O4ⁱⁱ	0.99	2.54	3.394 (2)	145
C10—H10B···Br2^iv	0.99	2.90	3.8905 (17)	175

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

Hydrogen-bond geometry (Å, º) for (3) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O4	0.89 (3)	2.02 (3)	2.890 (2)	167 (2)
N1—H1B···O1ⁱ	0.86 (3)	2.16 (3)	2.938 (2)	150 (2)
N1—H1B···O2ⁱⁱ	0.86 (3)	2.28 (3)	2.964 (2)	136 (2)
O2—H2···O4	0.82 (3)	1.79 (4)	2.5224 (16)	148 (5)
O2—H2···O3ⁱⁱⁱ	0.82 (3)	2.55 (4)	3.0678 (18)	122 (4)
O4—H4···O2	0.82 (3)	1.80 (4)	2.5224 (16)	147 (4)
C7—H7A···O4ⁱⁱ	0.99	2.55	3.402 (2)	145
C10—H10B···Br2^iv	0.99	2.91	3.8946 (17)	174

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

Experimental details

	130 K	145 K	180 K
Crystal data
Chemical formula	C₄H₁₀NO⁺·C₆HBr₂O₄⁻	C₄H₁₀NO⁺·C₆HBr₂O₄⁻	C₄H₁₀NO⁺·C₆HBr₂O₄⁻
M_r	385.01	385.01	385.01
Crystal system, space group	Triclinic, P1	Triclinic, P1	Triclinic, P1
a, b, c (Å)	8.62046 (19), 9.2129 (2), 9.4257 (2)	8.62293 (18), 9.21849 (19), 9.4354 (2)	8.62824 (17), 9.23087 (18), 9.46007 (19)
α, β, γ (°)	93.5208 (7), 112.9139 (7), 115.9757 (7)	93.5239 (7), 112.9190 (7), 115.9777 (7)	93.5321 (7), 112.9738 (7), 115.9508 (7)
V (Å³)	595.05 (3)	596.13 (3)	598.67 (3)
Z	2	2	2
Radiation type	Mo Kα	Mo Kα	Mo Kα
µ (mm⁻¹)	6.84	6.83	6.80
Crystal size (mm)	0.40 × 0.34 × 0.18	0.40 × 0.34 × 0.18	0.40 × 0.34 × 0.18

Data collection
Diffractometer	Rigaku R-AXIS RAPIDII diffractometer	Rigaku R-AXIS RAPIDII diffractometer	Rigaku R-AXIS RAPIDII diffractometer
Absorption correction	Numerical (NUMABS; Higashi, 1999)	Numerical (NUMABS; Higashi, 1999)	Numerical (NUMABS; Higashi, 1999)
T_min, T_max	0.096, 0.292	0.098, 0.292	0.098, 0.294
No. of measured, independent and observed [I > 2σ(I)] reflections	18162, 3468, 3183	18176, 3473, 3181	18199, 3487, 3188
R_int	0.026	0.028	0.026
(sin θ/λ)_max (Å⁻¹)	0.704	0.704	0.703

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.017, 0.046, 1.14	0.018, 0.046, 1.10	0.019, 0.048, 1.09
No. of reflections	3468	3473	3487
No. of parameters	178	178	178
No. of restraints	2	2	2
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement	H atoms treated by a mixture of independent and constrained refinement	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.50, −0.37	0.48, −0.44	0.59, −0.45

Computer programs: RAPID-AUTO (Rigaku, 2006), SIR92 (Altomare et al., 1994), SHELXL2014 (Sheldrick, 2015), SHELXL2014/7 (Sheldrick, 2015), ORTEP-3 for Windows (Farrugia, 2012), CrystalStructure (Rigaku, 2010) and PLATON (Spek, 2009).

References

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Volume 71| Part 10| October 2015| Pages 1226-1229

doi:10.1107/S2056989015017272

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