Benzamidinium tetra­hydro­penta­borate sesquihydrate

Portalone, G.

doi:10.1107/S1600536808017522

organic compounds

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ISSN: 2056-9890

Volume 64| Part 7| July 2008| Pages o1282-o1283

doi:10.1107/S1600536808017522

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Benzamidinium tetrahydropentaborate sesquihydrate

Gustavo Portalone ^a ^*

^aChemistry Department, University of Rome "La Sapienza", P.le A. Moro 5, I-00185 Rome, Italy
^*Correspondence e-mail: g.portalone@caspur.it

(Received 29 May 2008; accepted 10 June 2008; online 19 June 2008)

The asymmetric unit of the title compound [systematic name: benzamidinium 3,3′,5,5′-tetrahydroxy-1,1′-spirobi[2,4,6-trioxa-1,3,5-triboracyclohexane](1−) sesquihydrate], C₇H₉N₂⁺·B₅H₄O₁₀⁻·1.5H₂O, is composed of two protonated benzamidinium cations, two tetrahydropentaborate anions and three water molecules of crystallization. The ions and water molecules are associated in the crystal structure by an extensive three-dimensional hydrogen-bonding network, which consists mainly of cation-to-anion N—H⋯O and anion-to-anion O—H⋯O hydrogen bonds.

Related literature

For crystal structure determinations of the tetrahydropentaborate anion, see: Loboda et al., (1993 , 1994 ); Wiebcke et al. (1993 ); Turdybekov et al. (1992 ); Freyhardt et al. (1994 ); Baber et al. (2004 ). For the computation of ring patterns formed by hydrogen bonds in crystal structures, see: Etter et al. (1990 ); Bernstein et al. (1995 ); Motherwell et al. (1999 ). For hydration in molecular crystals, see: Gillon et al. (2003 ).

Experimental

Crystal data

C₇H₉N₂⁺·B₅H₄O₁₀⁻·1.5H₂O
M_r = 366.27
Triclinic, $[P \overline 1]$
a = 8.22314 (19) Å
b = 10.7814 (2) Å
c = 19.1997 (3) Å
α = 75.9475 (11)°
β = 85.4458 (16)°
γ = 73.6979 (13)°
V = 1584.74 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.14 mm⁻¹
T = 298 (2) K
0.15 × 0.12 × 0.10 mm

Data collection

Oxford Diffraction Xcalibur S CCD diffractometer
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ) T_min = 0.975, T_max = 0.988
142668 measured reflections
9063 independent reflections
5688 reflections with I > 2σ(I)
R_int = 0.050

Refinement

R[F² > 2σ(F²)] = 0.041
wR(F²) = 0.098
S = 0.99
9063 reflections
542 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2⋯O3ⁱ	0.83 (2)	2.04 (2)	2.8562 (13)	167.4 (18)
O4—H4⋯O6Aⁱⁱ	0.87 (2)	2.00 (2)	2.8361 (13)	161.3 (18)
O7—H7⋯O5Aⁱⁱⁱ	0.89 (2)	1.80 (2)	2.6877 (13)	177 (2)
O9—H9⋯O1A^iv	0.87 (2)	1.91 (2)	2.7784 (14)	174.6 (19)
O2A—H2A⋯O10^iv	0.87 (2)	1.84 (2)	2.7050 (14)	174.5 (17)
O4A—H4A⋯O6ⁱⁱⁱ	0.89 (2)	1.79 (2)	2.6735 (13)	178 (2)
O7A—H7A⋯O5ⁱⁱ	0.92 (2)	1.93 (2)	2.8085 (15)	160 (2)
O9A—H9A⋯O2W	0.87 (2)	2.18 (2)	2.9474 (16)	147.4 (18)
N1—H11⋯O1W	0.870 (18)	2.059 (18)	2.8756 (18)	156.0 (16)
N1—H12⋯O2A^v	0.872 (18)	1.996 (18)	2.8484 (15)	165.7 (15)
N2—H21⋯O1W	0.893 (17)	2.330 (17)	3.0892 (18)	142.8 (14)
N2—H22⋯O4A	0.858 (17)	2.025 (18)	2.8772 (16)	172.0 (15)
N1A—H11A⋯O10A	0.869 (19)	2.238 (19)	3.0084 (18)	147.7 (16)
N1A—H12A⋯O8	0.892 (19)	2.12 (2)	2.9646 (17)	157.4 (16)
N2A—H21A⋯O2W^iv	0.86 (2)	2.01 (2)	2.8703 (18)	175.0 (18)
N2A—H22A⋯O9	0.891 (19)	2.181 (19)	3.0717 (16)	178.4 (16)
O1W—H11W⋯O1^vi	0.82 (2)	2.10 (2)	2.9180 (15)	173 (2)
O1W—H12W⋯O4^vii	0.85 (2)	2.22 (2)	3.0033 (18)	153 (2)
O2W—H21W⋯O3W	0.93 (2)	1.92 (2)	2.8199 (19)	163 (2)
O2W—H22W⋯O7^viii	0.91 (2)	1.90 (2)	2.8016 (14)	169.3 (19)
O3W—H31W⋯O3W^ix	0.72 (3)	2.488 (10)	3.003 (3)	130.5 (17)
O3W—H32W⋯O7A	0.98 (3)	2.05 (3)	2.983 (2)	159 (2)
Symmetry codes: (i) -x, -y+1, -z+2; (ii) -x, -y+1, -z+1; (iii) -x+1, -y+1, -z+1; (iv) -x, -y+2, -z+1; (v) -x+1, -y+2, -z; (vi) x, y, z-1; (vii) x+1, y, z-1; (viii) x-1, y, z; (ix) -x-1, -y+1, -z+1.

Data collection: CrysAlis CCD (Oxford Diffraction 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ); cell refinement: CrysAlis RED(Oxford Diffraction 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ); data reduction: CrysAlis RED; program(s) used to solve structure: SIR97 (Altomare et al., 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808017522/rz2220sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808017522/rz2220Isup2.hkl

checkCIF report

Comment top

The asymmetric unit of the title compound (Fig. 1) comprises two planar benzamidinium cations, two tetrahydropentaborate anions and three water molecules of crystallization. The anions consist of a central BO₄ tetrahedron fused to four trigonal planar BO₃(OH) units. Both cations and the anions show normal geometric parameters (Table 1). Analysis of the crystal packing (Fig. 2) shows that adjacent [B₅O₆(OH)₄]^- units are hydrogen bonded to form eight-membered rings of graph set R²₂(8) (Etter et al., 1990; Bernstein et al., 1995; Motherwell et al., 1999). This anion-to-anion hydrogen-bonding framework is supplemented by the formation of five hydrogen bonds from each benzamidinium cation to adjacent [B₅O₆(OH)₄]^- anions (Table 2). Interestingly, two of the three water molecules of crystallization form hydrogen bonds which involve all the available hydrogen-bond donor/acceptor sites, at variance with what has been found in a survey of 3315 organic hydrate crystal structures. In this study (Gillon et al., 2003) it has been shown that the most common environment is one in which water forms three hydrogen bonds, two as donor and one as acceptor.

Related literature top

For crystal structure determinations of the tetrahydropentaborate anion, see: Loboda et al., (1993, 1994); Wiebcke et al. (1993); Turdybekov et al. (1992); Freyhardt et al. (1994); Baber et al. (2004). For the computation of ring patterns formed by hydrogen bonds in crystal structures, see: Etter et al. (1990); Bernstein et al. (1995); Motherwell et al. (1999). For hydration in molecular crystals, see: Gillon et al. (2003).

Experimental top

B(OH)₃ (90 mg, 0.15 mmol, Sigma Aldrich at 99.5% purity) was added to a stirred solution of benzamidine, C₇H₈N₂, (12 mg, 0.1 mmol, Fluka at 95% purity) in water (10 ml) and heated under reflux for 3 h. After cooling the solution to ambient temperature, crystals suitable for single-crystal X-ray diffraction were grown by slow evaporation of the solvent over several days.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. The molecular structure of the title compound, showing the atom-labelling scheme. Displacements ellipsoids are at the 50% probability level. Hydrogen bonding is indicated by dashed lines.
	Fig. 2. Crystal packing diagram for the title compound viewed approximately down the a axis. All atoms are shown as small spheres of arbitrary radii. For the sake of clarity, H atoms not involved in hydrogen bonding are omitted. Hydrogen bonding is indicated by dashed lines.

benzamidinium 3,3',5,5'-tetrahydroxy-1,1'-spirobi[2,4,6-trioxa-1,3,5-triboracyclohexane](1-) 1.5-hydrate top

Crystal data top

C₇H₉N₂⁺·B₅H₄O₁₀⁻·1.5H₂O	Z = 4
M_r = 366.27	F(000) = 756
Triclinic, P1	D_x = 1.535 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.22314 (19) Å	Cell parameters from 36413 reflections
b = 10.7814 (2) Å	θ = 2.6–32.6°
c = 19.1997 (3) Å	µ = 0.14 mm⁻¹
α = 75.9475 (11)°	T = 298 K
β = 85.4458 (16)°	Block, colourless
γ = 73.6979 (13)°	0.15 × 0.12 × 0.10 mm
V = 1584.74 (5) Å³

Data collection top

Oxford Diffraction Xcalibur S CCD diffractometer	9063 independent reflections
Radiation source: Enhance (Mo) X-ray source	5688 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.050
Detector resolution: 16.0696 pixels mm^-1	θ_max = 30.0°, θ_min = 2.6°
ω and ϕ scans	h = −11→11
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	k = −15→15
T_min = 0.975, T_max = 0.988	l = −27→27
142668 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.041	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.098	H atoms treated by a mixture of independent and constrained refinement
S = 0.99	w = 1/[σ²(F_o²) + (0.0514P)²] where P = (F_o² + 2F_c²)/3
9063 reflections	(Δ/σ)_max = 0.001
542 parameters	Δρ_max = 0.23 e Å⁻³
1 restraint	Δρ_min = −0.22 e Å⁻³

Crystal data top

C₇H₉N₂⁺·B₅H₄O₁₀⁻·1.5H₂O	γ = 73.6979 (13)°
M_r = 366.27	V = 1584.74 (5) Å³
Triclinic, P1	Z = 4
a = 8.22314 (19) Å	Mo Kα radiation
b = 10.7814 (2) Å	µ = 0.14 mm⁻¹
c = 19.1997 (3) Å	T = 298 K
α = 75.9475 (11)°	0.15 × 0.12 × 0.10 mm
β = 85.4458 (16)°

Data collection top

Oxford Diffraction Xcalibur S CCD diffractometer	9063 independent reflections
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	5688 reflections with I > 2σ(I)
T_min = 0.975, T_max = 0.988	R_int = 0.050
142668 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.041	1 restraint
wR(F²) = 0.098	H atoms treated by a mixture of independent and constrained refinement
S = 0.99	Δρ_max = 0.23 e Å⁻³
9063 reflections	Δρ_min = −0.22 e Å⁻³
542 parameters

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	U_iso*/U_eq
B1	0.15368 (18)	0.67509 (13)	0.78017 (7)	0.0240 (3)
O1	0.18508 (11)	0.67022 (8)	0.85446 (4)	0.0285 (2)
B2	0.10340 (19)	0.61230 (14)	0.91179 (7)	0.0264 (3)
O2	0.13937 (14)	0.61947 (10)	0.97783 (5)	0.0411 (3)
H2	0.088 (2)	0.5797 (18)	1.0104 (10)	0.061 (5)*
O3	−0.01246 (12)	0.54462 (9)	0.90282 (4)	0.0324 (2)
O4	−0.14621 (13)	0.46036 (10)	0.82903 (6)	0.0414 (3)
H4	−0.146 (2)	0.4444 (19)	0.7868 (11)	0.065 (6)*
B3	−0.03994 (19)	0.53439 (14)	0.83403 (7)	0.0275 (3)
O5	0.03619 (11)	0.59533 (9)	0.77633 (4)	0.0298 (2)
O6	0.31411 (11)	0.61782 (8)	0.74602 (4)	0.0276 (2)
O7	0.49090 (14)	0.60254 (10)	0.64314 (5)	0.0415 (3)
H7	0.536 (3)	0.521 (2)	0.6692 (12)	0.082 (7)*
O8	0.25892 (12)	0.78921 (9)	0.63891 (4)	0.0337 (2)
B4	0.3560 (2)	0.66751 (14)	0.67700 (7)	0.0282 (3)
O9	0.05933 (13)	0.99063 (9)	0.63637 (5)	0.0370 (2)
H9	−0.009 (3)	1.037 (2)	0.6630 (11)	0.071 (6)*
O10	0.08133 (11)	0.81424 (8)	0.74163 (4)	0.0286 (2)
B5	0.13056 (19)	0.86493 (14)	0.67397 (7)	0.0261 (3)
B1A	0.20283 (19)	0.70679 (14)	0.31266 (7)	0.0251 (3)
O1A	0.14676 (11)	0.85043 (8)	0.27918 (4)	0.0294 (2)
B2A	0.22073 (19)	0.90684 (14)	0.21888 (7)	0.0256 (3)
O2A	0.16712 (13)	1.03877 (9)	0.18762 (5)	0.0331 (2)
H2A	0.088 (2)	1.0818 (18)	0.2128 (10)	0.058 (6)*
O3A	0.35330 (12)	0.83347 (9)	0.18527 (5)	0.0347 (2)
O4A	0.55788 (14)	0.63416 (10)	0.18374 (5)	0.0400 (3)
H4A	0.602 (3)	0.551 (2)	0.2064 (11)	0.077 (6)*
B3A	0.4266 (2)	0.70280 (14)	0.21817 (7)	0.0277 (3)
O5A	0.36698 (11)	0.64584 (8)	0.28257 (4)	0.0304 (2)
O6A	0.08059 (12)	0.63966 (9)	0.29702 (5)	0.0338 (2)
O7A	−0.14440 (18)	0.53852 (17)	0.33468 (7)	0.0770 (5)
H7A	−0.126 (3)	0.513 (2)	0.2918 (12)	0.094 (7)*
O8A	−0.04403 (13)	0.63084 (11)	0.41341 (5)	0.0448 (3)
B4A	−0.0342 (2)	0.60380 (18)	0.34663 (9)	0.0398 (4)
O9A	0.09860 (16)	0.66666 (12)	0.50576 (5)	0.0491 (3)
H9A	0.018 (3)	0.641 (2)	0.5317 (11)	0.075 (6)*
O10A	0.21717 (11)	0.69028 (9)	0.38973 (4)	0.0302 (2)
B5A	0.0913 (2)	0.66232 (15)	0.43589 (8)	0.0318 (3)
N1	0.67173 (18)	0.80236 (14)	−0.07944 (6)	0.0402 (3)
H11	0.631 (2)	0.7525 (17)	−0.0989 (9)	0.051 (5)*
H12	0.716 (2)	0.8610 (17)	−0.1079 (9)	0.050 (5)*
N2	0.61716 (17)	0.68505 (12)	0.03102 (7)	0.0385 (3)
H21	0.581 (2)	0.6316 (16)	0.0105 (9)	0.048 (5)*
H22	0.599 (2)	0.6779 (16)	0.0763 (10)	0.049 (5)*
C1	0.73291 (16)	0.87110 (13)	0.02400 (7)	0.0301 (3)
C2	0.71988 (18)	1.00220 (14)	−0.01273 (8)	0.0370 (3)
H2B	0.6713	1.0354	−0.0603	0.044*
C3	0.7765 (2)	1.08450 (15)	0.01889 (9)	0.0471 (4)
H3	0.7675	1.1756	−0.0066	0.057*
C4	0.8452 (2)	1.03783 (17)	0.08617 (10)	0.0528 (4)
H4B	0.8834	1.0965	0.1083	0.063*
C5	0.8603 (2)	0.90783 (18)	0.12271 (9)	0.0514 (4)
H5	0.9105	0.8751	0.1700	0.062*
C6	0.80389 (19)	0.82453 (15)	0.09177 (8)	0.0412 (3)
H6	0.8139	0.7334	0.1175	0.049*
C7	0.67193 (16)	0.78329 (13)	−0.00935 (7)	0.0297 (3)
N1A	0.3078 (2)	0.85153 (14)	0.48086 (8)	0.0550 (4)
H11A	0.325 (2)	0.8023 (18)	0.4498 (10)	0.058 (5)*
H12A	0.268 (2)	0.8266 (18)	0.5252 (11)	0.061 (5)*
N2A	0.2464 (2)	1.06351 (15)	0.49387 (7)	0.0478 (4)
H21A	0.254 (2)	1.1441 (19)	0.4800 (10)	0.063 (6)*
H22A	0.193 (2)	1.0430 (17)	0.5356 (10)	0.058 (5)*
C1A	0.38252 (19)	1.01425 (14)	0.38368 (7)	0.0358 (3)
C2A	0.5160 (2)	0.92500 (17)	0.35919 (8)	0.0490 (4)
H23A	0.5592	0.8364	0.3889	0.059*
C3A	0.5890 (2)	0.96110 (19)	0.29228 (9)	0.0571 (5)
H3A	0.6822	0.8976	0.2750	0.069*
C4A	0.5286 (2)	1.08720 (19)	0.25051 (8)	0.0550 (5)
H41A	0.5811	1.1131	0.2042	0.066*
C5A	0.3948 (2)	1.17638 (17)	0.27401 (8)	0.0493 (4)
H5A	0.3524	1.2648	0.2441	0.059*
C6A	0.3197 (2)	1.14088 (15)	0.34044 (7)	0.0411 (3)
H6A	0.2240	1.2038	0.3567	0.049*
C7A	0.30793 (19)	0.97547 (15)	0.45592 (7)	0.0378 (3)
O1W	0.53676 (17)	0.59539 (14)	−0.10037 (7)	0.0554 (3)
H11W	0.441 (3)	0.614 (2)	−0.1163 (13)	0.089*
H12W	0.603 (3)	0.545 (2)	−0.1244 (12)	0.089*
O2W	−0.25372 (16)	0.66371 (12)	0.54656 (6)	0.0512 (3)
H21W	−0.296 (3)	0.649 (2)	0.5068 (12)	0.082*
H22W	−0.335 (3)	0.651 (2)	0.5809 (12)	0.082*
O3W	−0.41457 (19)	0.58780 (16)	0.44572 (9)	0.0732 (4)
H31W	−0.492 (4)	0.568 (2)	0.4515 (8)	0.117*
H32W	−0.329 (3)	0.549 (3)	0.4128 (15)	0.117*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
B1	0.0284 (8)	0.0219 (7)	0.0200 (6)	−0.0071 (6)	0.0052 (6)	−0.0030 (5)
O1	0.0352 (5)	0.0315 (5)	0.0218 (4)	−0.0160 (4)	0.0038 (4)	−0.0049 (4)
B2	0.0314 (8)	0.0229 (7)	0.0236 (6)	−0.0070 (6)	0.0053 (6)	−0.0052 (5)
O2	0.0598 (7)	0.0498 (6)	0.0233 (5)	−0.0322 (6)	0.0054 (5)	−0.0078 (4)
O3	0.0402 (5)	0.0402 (5)	0.0224 (4)	−0.0222 (5)	0.0081 (4)	−0.0070 (4)
O4	0.0500 (6)	0.0522 (6)	0.0330 (5)	−0.0315 (5)	0.0091 (5)	−0.0129 (5)
B3	0.0278 (8)	0.0276 (7)	0.0271 (7)	−0.0081 (7)	0.0052 (6)	−0.0071 (6)
O5	0.0369 (5)	0.0338 (5)	0.0222 (4)	−0.0170 (4)	0.0050 (4)	−0.0061 (4)
O6	0.0298 (5)	0.0230 (4)	0.0245 (4)	−0.0036 (4)	0.0067 (4)	−0.0013 (3)
O7	0.0450 (6)	0.0287 (5)	0.0366 (5)	0.0006 (5)	0.0203 (5)	−0.0003 (4)
O8	0.0427 (6)	0.0266 (5)	0.0232 (4)	−0.0019 (4)	0.0090 (4)	−0.0016 (4)
B4	0.0306 (8)	0.0252 (7)	0.0262 (7)	−0.0073 (7)	0.0062 (6)	−0.0038 (6)
O9	0.0433 (6)	0.0262 (5)	0.0293 (5)	0.0011 (5)	0.0089 (4)	0.0009 (4)
O10	0.0313 (5)	0.0230 (4)	0.0251 (4)	−0.0024 (4)	0.0077 (4)	−0.0021 (3)
B5	0.0283 (8)	0.0250 (7)	0.0234 (6)	−0.0065 (7)	0.0033 (6)	−0.0046 (6)
B1A	0.0308 (8)	0.0224 (7)	0.0213 (6)	−0.0086 (6)	0.0070 (6)	−0.0041 (5)
O1A	0.0314 (5)	0.0227 (4)	0.0290 (4)	−0.0046 (4)	0.0097 (4)	−0.0025 (3)
B2A	0.0287 (8)	0.0234 (7)	0.0225 (6)	−0.0061 (7)	0.0020 (6)	−0.0030 (5)
O2A	0.0392 (6)	0.0231 (5)	0.0298 (5)	−0.0035 (5)	0.0113 (4)	−0.0022 (4)
O3A	0.0403 (6)	0.0254 (5)	0.0273 (4)	−0.0006 (4)	0.0132 (4)	0.0008 (4)
O4A	0.0451 (6)	0.0278 (5)	0.0310 (5)	0.0040 (5)	0.0176 (5)	0.0016 (4)
B3A	0.0313 (8)	0.0247 (7)	0.0243 (6)	−0.0062 (7)	0.0064 (6)	−0.0041 (6)
O5A	0.0340 (5)	0.0222 (4)	0.0273 (4)	−0.0031 (4)	0.0108 (4)	−0.0004 (3)
O6A	0.0428 (6)	0.0401 (5)	0.0258 (4)	−0.0227 (5)	0.0096 (4)	−0.0107 (4)
O7A	0.0885 (10)	0.1351 (13)	0.0538 (7)	−0.0873 (10)	0.0356 (7)	−0.0531 (8)
O8A	0.0456 (6)	0.0691 (7)	0.0348 (5)	−0.0343 (6)	0.0169 (5)	−0.0235 (5)
B4A	0.0435 (10)	0.0510 (10)	0.0350 (8)	−0.0250 (8)	0.0115 (7)	−0.0181 (7)
O9A	0.0629 (7)	0.0669 (7)	0.0265 (5)	−0.0346 (6)	0.0105 (5)	−0.0115 (5)
O10A	0.0352 (5)	0.0343 (5)	0.0226 (4)	−0.0143 (4)	0.0043 (4)	−0.0054 (4)
B5A	0.0396 (9)	0.0303 (8)	0.0263 (7)	−0.0122 (7)	0.0066 (6)	−0.0066 (6)
N1	0.0556 (8)	0.0442 (7)	0.0269 (6)	−0.0247 (7)	0.0057 (6)	−0.0083 (5)
N2	0.0525 (8)	0.0360 (7)	0.0302 (6)	−0.0198 (6)	0.0052 (6)	−0.0062 (5)
C1	0.0297 (7)	0.0317 (7)	0.0289 (6)	−0.0092 (6)	0.0054 (5)	−0.0079 (5)
C2	0.0374 (8)	0.0330 (7)	0.0385 (7)	−0.0088 (6)	0.0037 (6)	−0.0065 (6)
C3	0.0453 (9)	0.0326 (8)	0.0653 (11)	−0.0120 (7)	0.0026 (8)	−0.0141 (7)
C4	0.0461 (10)	0.0553 (10)	0.0698 (11)	−0.0189 (8)	0.0000 (8)	−0.0323 (9)
C5	0.0511 (10)	0.0648 (11)	0.0447 (9)	−0.0196 (9)	−0.0080 (7)	−0.0175 (8)
C6	0.0459 (9)	0.0409 (8)	0.0370 (7)	−0.0136 (7)	−0.0034 (6)	−0.0062 (6)
C7	0.0295 (7)	0.0286 (7)	0.0286 (6)	−0.0062 (6)	0.0039 (5)	−0.0055 (5)
N1A	0.0941 (12)	0.0436 (8)	0.0342 (7)	−0.0350 (8)	0.0173 (8)	−0.0086 (6)
N2A	0.0679 (10)	0.0420 (8)	0.0358 (7)	−0.0226 (7)	0.0164 (7)	−0.0096 (6)
C1A	0.0457 (9)	0.0414 (8)	0.0259 (6)	−0.0220 (8)	0.0011 (6)	−0.0067 (6)
C2A	0.0588 (11)	0.0464 (9)	0.0380 (8)	−0.0137 (9)	0.0055 (8)	−0.0050 (7)
C3A	0.0572 (11)	0.0706 (12)	0.0416 (9)	−0.0162 (10)	0.0106 (8)	−0.0142 (8)
C4A	0.0590 (11)	0.0799 (13)	0.0296 (7)	−0.0331 (11)	0.0037 (7)	−0.0037 (8)
C5A	0.0600 (11)	0.0554 (10)	0.0319 (7)	−0.0250 (9)	−0.0059 (7)	0.0039 (7)
C6A	0.0472 (9)	0.0451 (8)	0.0332 (7)	−0.0181 (7)	−0.0022 (6)	−0.0058 (6)
C7A	0.0462 (9)	0.0422 (8)	0.0293 (7)	−0.0219 (7)	0.0014 (6)	−0.0055 (6)
O1W	0.0458 (7)	0.0704 (9)	0.0604 (8)	−0.0210 (7)	−0.0036 (6)	−0.0271 (6)
O2W	0.0620 (8)	0.0562 (7)	0.0451 (6)	−0.0315 (6)	0.0243 (6)	−0.0193 (5)
O3W	0.0637 (10)	0.0796 (10)	0.0819 (10)	−0.0187 (8)	0.0071 (8)	−0.0325 (8)

Geometric parameters (Å, º) top

B1—O1	1.4555 (15)	N1—H11	0.870 (18)
B1—O6	1.4674 (17)	N1—H12	0.872 (18)
B1—O10	1.4771 (15)	N2—C7	1.3188 (16)
B1—O5	1.4788 (16)	N2—H21	0.893 (17)
O1—B2	1.3553 (15)	N2—H22	0.858 (17)
B2—O2	1.3494 (16)	C1—C6	1.3874 (19)
B2—O3	1.3955 (16)	C1—C2	1.3962 (18)
O2—H2	0.83 (2)	C1—C7	1.4729 (18)
O3—B3	1.3929 (16)	C2—C3	1.382 (2)
O4—B3	1.3608 (17)	C2—H2B	0.9700
O4—H4	0.87 (2)	C3—C4	1.372 (2)
B3—O5	1.3484 (16)	C3—H3	0.9700
O6—B4	1.3593 (16)	C4—C5	1.382 (2)
O7—B4	1.3472 (19)	C4—H4B	0.9700
O7—H7	0.89 (2)	C5—C6	1.383 (2)
O8—B5	1.3798 (18)	C5—H5	0.9700
O8—B4	1.3900 (17)	C6—H6	0.9700
O9—B5	1.3592 (17)	N1A—C7A	1.3057 (19)
O9—H9	0.87 (2)	N1A—H11A	0.869 (19)
O10—B5	1.3588 (15)	N1A—H12A	0.892 (19)
B1A—O10A	1.4572 (15)	N2A—C7A	1.302 (2)
B1A—O5A	1.4664 (18)	N2A—H21A	0.86 (2)
B1A—O6A	1.4785 (16)	N2A—H22A	0.891 (19)
B1A—O1A	1.4788 (16)	C1A—C2A	1.377 (2)
O1A—B2A	1.3544 (16)	C1A—C6A	1.394 (2)
B2A—O2A	1.3613 (16)	C1A—C7A	1.4839 (18)
B2A—O3A	1.3721 (18)	C2A—C3A	1.389 (2)
O2A—H2A	0.87 (2)	C2A—H23A	0.9700
O3A—B3A	1.3778 (17)	C3A—C4A	1.376 (3)
O4A—B3A	1.3514 (19)	C3A—H3A	0.9700
O4A—H4A	0.89 (2)	C4A—C5A	1.370 (3)
B3A—O5A	1.3601 (16)	C4A—H41A	0.9700
O6A—B4A	1.3533 (18)	C5A—C6A	1.388 (2)
O7A—B4A	1.3559 (19)	C5A—H5A	0.9700
O7A—H7A	0.92 (2)	C6A—H6A	0.9700
O8A—B4A	1.3737 (18)	O1W—H11W	0.82 (2)
O8A—B5A	1.3781 (18)	O1W—H12W	0.85 (2)
O9A—B5A	1.3604 (18)	O2W—H21W	0.93 (2)
O9A—H9A	0.87 (2)	O2W—H22W	0.91 (2)
O10A—B5A	1.3592 (17)	O3W—H31W	0.72 (3)
N1—C7	1.3110 (17)	O3W—H32W	0.98 (3)

O1—B1—O6	109.01 (10)	C7—N1—H12	122.4 (11)
O1—B1—O10	109.67 (10)	H11—N1—H12	117.7 (16)
O6—B1—O10	110.02 (9)	C7—N2—H21	119.9 (11)
O1—B1—O5	110.83 (9)	C7—N2—H22	121.9 (11)
O6—B1—O5	107.59 (10)	H21—N2—H22	117.4 (15)
O10—B1—O5	109.70 (10)	C6—C1—C2	119.52 (13)
B2—O1—B1	124.25 (10)	C6—C1—C7	120.52 (12)
O2—B2—O1	118.37 (12)	C2—C1—C7	119.97 (12)
O2—B2—O3	120.85 (11)	C3—C2—C1	119.80 (14)
O1—B2—O3	120.77 (11)	C3—C2—H2B	120.1
B2—O2—H2	113.3 (13)	C1—C2—H2B	120.1
B3—O3—B2	118.95 (10)	C4—C3—C2	120.24 (14)
B3—O4—H4	113.7 (13)	C4—C3—H3	119.9
O5—B3—O4	122.84 (12)	C2—C3—H3	119.9
O5—B3—O3	120.79 (11)	C3—C4—C5	120.45 (14)
O4—B3—O3	116.37 (11)	C3—C4—H4B	119.8
B3—O5—B1	124.05 (10)	C5—C4—H4B	119.8
B4—O6—B1	123.03 (10)	C4—C5—C6	119.90 (15)
B4—O7—H7	111.2 (13)	C4—C5—H5	120.0
B5—O8—B4	119.26 (10)	C6—C5—H5	120.0
O7—B4—O6	122.12 (12)	C5—C6—C1	120.09 (14)
O7—B4—O8	117.66 (11)	C5—C6—H6	120.0
O6—B4—O8	120.22 (13)	C1—C6—H6	120.0
B5—O9—H9	111.6 (13)	N1—C7—N2	119.55 (13)
B5—O10—B1	122.74 (11)	N1—C7—C1	120.16 (12)
O10—B5—O9	123.50 (13)	N2—C7—C1	120.28 (12)
O10—B5—O8	120.89 (11)	C7A—N1A—H11A	116.7 (12)
O9—B5—O8	115.61 (11)	C7A—N1A—H12A	119.3 (12)
O10A—B1A—O5A	109.86 (11)	H11A—N1A—H12A	122.5 (17)
O10A—B1A—O6A	111.11 (9)	C7A—N2A—H21A	122.3 (13)
O5A—B1A—O6A	106.98 (10)	C7A—N2A—H22A	121.0 (11)
O10A—B1A—O1A	108.47 (10)	H21A—N2A—H22A	116.7 (17)
O5A—B1A—O1A	110.50 (9)	C2A—C1A—C6A	119.51 (13)
O6A—B1A—O1A	109.93 (11)	C2A—C1A—C7A	119.90 (13)
B2A—O1A—B1A	122.37 (10)	C6A—C1A—C7A	120.59 (14)
O1A—B2A—O2A	122.20 (13)	C1A—C2A—C3A	120.39 (16)
O1A—B2A—O3A	121.68 (11)	C1A—C2A—H23A	119.8
O2A—B2A—O3A	116.12 (11)	C3A—C2A—H23A	119.8
B2A—O2A—H2A	112.4 (12)	C4A—C3A—C2A	119.79 (18)
B2A—O3A—B3A	119.19 (10)	C4A—C3A—H3A	120.1
B3A—O4A—H4A	115.1 (14)	C2A—C3A—H3A	120.1
O4A—B3A—O5A	121.78 (12)	C5A—C4A—C3A	120.32 (15)
O4A—B3A—O3A	117.46 (11)	C5A—C4A—H41A	119.8
O5A—B3A—O3A	120.76 (13)	C3A—C4A—H41A	119.8
B3A—O5A—B1A	122.46 (10)	C4A—C5A—C6A	120.38 (15)
B4A—O6A—B1A	121.68 (10)	C4A—C5A—H5A	119.8
B4A—O7A—H7A	113.7 (14)	C6A—C5A—H5A	119.8
B4A—O8A—B5A	118.13 (11)	C5A—C6A—C1A	119.59 (16)
O6A—B4A—O7A	123.06 (13)	C5A—C6A—H6A	120.2
O6A—B4A—O8A	121.13 (13)	C1A—C6A—H6A	120.2
O7A—B4A—O8A	115.80 (13)	N2A—C7A—N1A	120.97 (14)
B5A—O9A—H9A	112.3 (13)	N2A—C7A—C1A	120.29 (13)
B5A—O10A—B1A	121.15 (11)	N1A—C7A—C1A	118.74 (14)
O10A—B5A—O9A	119.12 (13)	H11W—O1W—H12W	107 (2)
O10A—B5A—O8A	121.56 (12)	H21W—O2W—H22W	102.8 (18)
O9A—B5A—O8A	119.33 (12)	H31W—O3W—H32W	118 (3)
C7—N1—H11	119.8 (11)

O6—B1—O1—B2	−124.83 (12)	O6A—B1A—O5A—B3A	99.35 (13)
O10—B1—O1—B2	114.67 (13)	O1A—B1A—O5A—B3A	−20.30 (16)
O5—B1—O1—B2	−6.59 (17)	O10A—B1A—O6A—B4A	17.60 (18)
B1—O1—B2—O2	−177.28 (12)	O5A—B1A—O6A—B4A	137.51 (13)
B1—O1—B2—O3	4.01 (19)	O1A—B1A—O6A—B4A	−102.48 (14)
O2—B2—O3—B3	−177.04 (12)	B1A—O6A—B4A—O7A	−177.91 (16)
O1—B2—O3—B3	1.64 (19)	B1A—O6A—B4A—O8A	1.3 (2)
B2—O3—B3—O5	−3.89 (19)	B5A—O8A—B4A—O6A	−17.0 (2)
B2—O3—B3—O4	176.05 (12)	B5A—O8A—B4A—O7A	162.24 (15)
O4—B3—O5—B1	−179.28 (12)	O5A—B1A—O10A—B5A	−140.66 (12)
O3—B3—O5—B1	0.7 (2)	O6A—B1A—O10A—B5A	−22.48 (17)
O1—B1—O5—B3	4.27 (17)	O1A—B1A—O10A—B5A	98.46 (13)
O6—B1—O5—B3	123.36 (12)	B1A—O10A—B5A—O9A	−170.58 (12)
O10—B1—O5—B3	−116.98 (13)	B1A—O10A—B5A—O8A	8.9 (2)
O1—B1—O6—B4	−141.66 (11)	B4A—O8A—B5A—O10A	12.0 (2)
O10—B1—O6—B4	−21.37 (16)	B4A—O8A—B5A—O9A	−168.55 (14)
O5—B1—O6—B4	98.08 (13)	C6—C1—C2—C3	−0.5 (2)
B1—O6—B4—O7	−169.70 (12)	C7—C1—C2—C3	179.67 (13)
B1—O6—B4—O8	10.48 (19)	C1—C2—C3—C4	0.0 (2)
B5—O8—B4—O7	−173.33 (12)	C2—C3—C4—C5	0.7 (3)
B5—O8—B4—O6	6.49 (19)	C3—C4—C5—C6	−0.9 (3)
O1—B1—O10—B5	137.70 (12)	C4—C5—C6—C1	0.3 (2)
O6—B1—O10—B5	17.80 (16)	C2—C1—C6—C5	0.4 (2)
O5—B1—O10—B5	−100.36 (13)	C7—C1—C6—C5	−179.81 (14)
B1—O10—B5—O9	176.52 (12)	C6—C1—C7—N1	−151.51 (14)
B1—O10—B5—O8	−3.40 (19)	C2—C1—C7—N1	28.3 (2)
B4—O8—B5—O10	−9.94 (19)	C6—C1—C7—N2	28.5 (2)
B4—O8—B5—O9	170.13 (12)	C2—C1—C7—N2	−151.66 (13)
O10A—B1A—O1A—B2A	133.89 (12)	C6A—C1A—C2A—C3A	0.8 (2)
O5A—B1A—O1A—B2A	13.41 (16)	C7A—C1A—C2A—C3A	−178.70 (15)
O6A—B1A—O1A—B2A	−104.44 (13)	C1A—C2A—C3A—C4A	0.6 (3)
B1A—O1A—B2A—O2A	179.00 (11)	C2A—C3A—C4A—C5A	−1.3 (3)
B1A—O1A—B2A—O3A	−0.22 (19)	C3A—C4A—C5A—C6A	0.5 (3)
O1A—B2A—O3A—B3A	−8.04 (19)	C4A—C5A—C6A—C1A	0.8 (2)
O2A—B2A—O3A—B3A	172.69 (11)	C2A—C1A—C6A—C5A	−1.5 (2)
B2A—O3A—B3A—O4A	−179.36 (12)	C7A—C1A—C6A—C5A	177.97 (13)
B2A—O3A—B3A—O5A	1.16 (19)	C2A—C1A—C7A—N2A	147.16 (16)
O4A—B3A—O5A—B1A	−165.33 (12)	C6A—C1A—C7A—N2A	−32.3 (2)
O3A—B3A—O5A—B1A	14.13 (19)	C2A—C1A—C7A—N1A	−31.8 (2)
O10A—B1A—O5A—B3A	−139.94 (12)	C6A—C1A—C7A—N1A	148.75 (15)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O3ⁱ	0.83 (2)	2.04 (2)	2.8562 (13)	167.4 (18)
O4—H4···O6Aⁱⁱ	0.87 (2)	2.00 (2)	2.8361 (13)	161.3 (18)
O7—H7···O5Aⁱⁱⁱ	0.89 (2)	1.80 (2)	2.6877 (13)	177 (2)
O9—H9···O1A^iv	0.87 (2)	1.91 (2)	2.7784 (14)	174.6 (19)
O2A—H2A···O10^iv	0.87 (2)	1.84 (2)	2.7050 (14)	174.5 (17)
O4A—H4A···O6ⁱⁱⁱ	0.89 (2)	1.79 (2)	2.6735 (13)	178 (2)
O7A—H7A···O5ⁱⁱ	0.92 (2)	1.93 (2)	2.8085 (15)	160 (2)
O9A—H9A···O2W	0.87 (2)	2.18 (2)	2.9474 (16)	147.4 (18)
N1—H11···O1W	0.870 (18)	2.059 (18)	2.8756 (18)	156.0 (16)
N1—H12···O2A^v	0.872 (18)	1.996 (18)	2.8484 (15)	165.7 (15)
N2—H21···O1W	0.893 (17)	2.330 (17)	3.0892 (18)	142.8 (14)
N2—H22···O4A	0.858 (17)	2.025 (18)	2.8772 (16)	172.0 (15)
N1A—H11A···O10A	0.869 (19)	2.238 (19)	3.0084 (18)	147.7 (16)
N1A—H12A···O8	0.892 (19)	2.12 (2)	2.9646 (17)	157.4 (16)
N2A—H21A···O2W^iv	0.86 (2)	2.01 (2)	2.8703 (18)	175.0 (18)
N2A—H22A···O9	0.891 (19)	2.181 (19)	3.0717 (16)	178.4 (16)
O1W—H11W···O1^vi	0.82 (2)	2.10 (2)	2.9180 (15)	173 (2)
O1W—H12W···O4^vii	0.85 (2)	2.22 (2)	3.0033 (18)	153 (2)
O2W—H21W···O3W	0.93 (2)	1.92 (2)	2.8199 (19)	163 (2)
O2W—H22W···O7^viii	0.91 (2)	1.90 (2)	2.8016 (14)	169.3 (19)
O3W—H31W···O3W^ix	0.72 (3)	2.488 (10)	3.003 (3)	130.5 (17)
O3W—H32W···O7A	0.98 (3)	2.05 (3)	2.983 (2)	159 (2)

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

Experimental details

Crystal data
Chemical formula	C₇H₉N₂⁺·B₅H₄O₁₀⁻·1.5H₂O
M_r	366.27
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	8.22314 (19), 10.7814 (2), 19.1997 (3)
α, β, γ (°)	75.9475 (11), 85.4458 (16), 73.6979 (13)
V (Å³)	1584.74 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.14
Crystal size (mm)	0.15 × 0.12 × 0.10

Data collection
Diffractometer	Oxford Diffraction Xcalibur S CCD diffractometer
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2006)
T_min, T_max	0.975, 0.988
No. of measured, independent and observed [I > 2σ(I)] reflections	142668, 9063, 5688
R_int	0.050
(sin θ/λ)_max (Å⁻¹)	0.703

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.041, 0.098, 0.99
No. of reflections	9063
No. of parameters	542
No. of restraints	1
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.22

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O3ⁱ	0.83 (2)	2.04 (2)	2.8562 (13)	167.4 (18)
O4—H4···O6Aⁱⁱ	0.87 (2)	2.00 (2)	2.8361 (13)	161.3 (18)
O7—H7···O5Aⁱⁱⁱ	0.89 (2)	1.80 (2)	2.6877 (13)	177 (2)
O9—H9···O1A^iv	0.87 (2)	1.91 (2)	2.7784 (14)	174.6 (19)
O2A—H2A···O10^iv	0.87 (2)	1.84 (2)	2.7050 (14)	174.5 (17)
O4A—H4A···O6ⁱⁱⁱ	0.89 (2)	1.79 (2)	2.6735 (13)	178 (2)
O7A—H7A···O5ⁱⁱ	0.92 (2)	1.93 (2)	2.8085 (15)	160 (2)
O9A—H9A···O2W	0.87 (2)	2.18 (2)	2.9474 (16)	147.4 (18)
N1—H11···O1W	0.870 (18)	2.059 (18)	2.8756 (18)	156.0 (16)
N1—H12···O2A^v	0.872 (18)	1.996 (18)	2.8484 (15)	165.7 (15)
N2—H21···O1W	0.893 (17)	2.330 (17)	3.0892 (18)	142.8 (14)
N2—H22···O4A	0.858 (17)	2.025 (18)	2.8772 (16)	172.0 (15)
N1A—H11A···O10A	0.869 (19)	2.238 (19)	3.0084 (18)	147.7 (16)
N1A—H12A···O8	0.892 (19)	2.12 (2)	2.9646 (17)	157.4 (16)
N2A—H21A···O2W^iv	0.86 (2)	2.01 (2)	2.8703 (18)	175.0 (18)
N2A—H22A···O9	0.891 (19)	2.181 (19)	3.0717 (16)	178.4 (16)
O1W—H11W···O1^vi	0.82 (2)	2.10 (2)	2.9180 (15)	173 (2)
O1W—H12W···O4^vii	0.85 (2)	2.22 (2)	3.0033 (18)	153 (2)
O2W—H21W···O3W	0.93 (2)	1.92 (2)	2.8199 (19)	163 (2)
O2W—H22W···O7^viii	0.91 (2)	1.90 (2)	2.8016 (14)	169.3 (19)
O3W—H31W···O3W^ix	0.72 (3)	2.488 (10)	3.003 (3)	130.5 (17)
O3W—H32W···O7A	0.98 (3)	2.05 (3)	2.983 (2)	159 (2)

Acknowledgements

We thank MIUR (Rome) for 2006 financial support of the project `X-ray diffractometry and spectrometry'.

References

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