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ISSN: 2056-9890

A 1:2 co-crystal of isonicotin­amide and propionic acid

aSchool of Chemistry, The University of Edinburgh, King's Buildings, West Mains Road, Edinburgh EH9 3JJ, Scotland, and bCambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, England
*Correspondence e-mail: s.parsons@ed.ac.uk

(Received 12 October 2004; accepted 8 November 2004; online 20 November 2004)

Isonicotin­amide has been shown to form many 1:1 co-crystals with monofunctional carboxyl­ic acids, but with propionic acid it forms a co-crystal containing two acid mol­ecules and one isonicotin­amide mol­ecule per formula unit, C6H6N2O·2C3H6O2. The crystal structure consists of `supermol­ecules' made up of of one isonicotin­amide mol­ecule and two acid mol­ecules, and the asymmetric unit contains two of these supermolecules. One of the acid mol­ecules is hydrogen bonded to the pyridine function, and the other to the amide function of the isonicotin­amide. Further N—H⋯O hydrogen bonds connect these supermol­ecules into chains which run along the [100] direction. The chains are linked into layers perpendicular to (010) by C—H⋯O and π-stacking interactions. The layers are then linked together by further C—H⋯O interactions.

Comment

Isonicotin­amide has been shown to crystallize with carboxyl­ic acids in a 1:1 stoichiometry to form a robust building block or `supermol­ecule' consisting of two amide and two acid mol­ecules, (I[link]) (Aakeröy et al., 2002[Aakeröy, C. B., Beatty, A. M. & Helfrich, B. A. (2002). J. Am. Chem. Soc. 124, 14425-14432.]). When a saturated solution of isonicotin­amide in warm propionic acid was allowed to cool, colourless crystalline laths were obtained. Single-crystal X-ray diffraction revealed these to be a co-crystal consisting of isonicotin­amide and propionic acid in a 1:2 ratio, viz. (II[link]).[link]

[Scheme 1]

Similar preparative routes with formic and acetic acids both yielded 1:1 co-crystals (Oswald, 2004[Oswald, I. D. H. (2004) PhD thesis, The University of Edinburgh, Scotland.]). Attempts to prepare a 1:1 co-crystal with propionic acid failed. For example, a 1:1 mixture of propionic acid and isonicotin­amide in ethanol yielded only crystals of (II[link]); even in the presence of excess isonicotin­amide, the only crystals obtained were isonicotin­amide itself and (II[link]).

The crystal structure of (II[link]) consists of supermol­ecules comprising two acid and one isonicotin­amide mol­ecule. One acid forms an R22(8) motif with the amide moiety (Bernstein et al., 1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). Another acid mol­ecule forms a hydrogen bond to the pyridine N atom, supported by a weaker C—H⋯O hydrogen bond (Fig. 1[link] and Table 1[link]). There are two supermol­ecules in the asymmetric unit and, in the terminology of Aakeröy et al. (2002[Aakeröy, C. B., Beatty, A. M. & Helfrich, B. A. (2002). J. Am. Chem. Soc. 124, 14425-14432.]), both are in the transtrans conform­ation.

The independent supermol­ecules hydrogen-bond together using the second amide donor and the carbonyl group from the propionic acid mol­ecules located at the pyridine end of the supermol­ecules. This builds up a helical chain in which successive supermol­ecules are aligned approximately perpendicular to one another (Figs. 2[link]–4[link][link]; hydrogen-bond dimensions are listed in Table 1[link]). The chains run along the a direction, and they comprise all the conventional N—H⋯O and O—H⋯O hydrogen bonds in the crystal structure (see Table 1[link]); additional C—H⋯O interactions (C5A—H5A⋯O2U and C5B—H5B⋯O2V) are also formed within the chains (Desiraju & Steiner, 1999[Desiraju, G. R. & Steiner, T. (1999). The Weak Hydro­gen Bond. IUCr Monographs on Crystallography, No. 9. Oxford University Press.]).

Successive helical chains are distributed along the c direction at z = ¼, ¾, …, etc. (Fig. 5[link]). Though there are no direct hydrogen-bonding interactions between neighbouring chains, weak C—H⋯O interactions are formed between chains located one lattice-repeat away from each other (e.g. the red and blue chains in Fig. 5[link]; see also Fig. 6[link]). These interactions involve C2A—H2A⋯O3T and C2B—H2B⋯O3S. Supermol­ecules in neighbouring chains are interleaved to produce stacks of supermol­ecules along a (Fig. 5[link]). Stacks containing only the supermol­ecules based on isonicotin­amide mol­ecule A occur at z = ½, while stacks containing only those based on mol­ecule B occur at z = 0, 1, … etc. Within the stacks, pairs of pyridine moieties are π-stacked across inversion centres (Fig. 7[link]). The stacking distances are 3.34 and 3.33 Å for the A and B pyridine rings, respectively.

Thus, layers are formed in the ac-plane by chains of hydrogen-bonded supermol­ecules linked by weak C—H⋯O and π-stacking interactions. The layers are connected via C—H⋯O hydrogen bonds involving pairs of C4T—H4T1⋯O2T and C4V—H4V1⋯O2S interactions disposed about inversion centres (Fig. 8[link]).

[Figure 1]
Figure 1
The two crystallographically independent supermol­ecules, with the atomic numbering. Displacement ellipsoids are drawn at the 30% probability level. Conventional hydrogen bonds are shown in heavy dashes and the H⋯O distances span 1.78 (4)–1.96 (4) Å (see Table 1[link]). The C—H⋯O hydrogen bonds (shown as open dashes) are quite weak for this type of interaction (2.73 and 2.72 Å).
[Figure 2]
Figure 2
Hydro­gen-bonded chains in the crystal structure of (II[link]). Hydro­gen bonds link supermol­ecules into chains. This view is approximately along the direct lattice direction [100]. Hydro­gen bonds are shown as dashed lines, weak C—H⋯O hydrogen bonds are shown in turquoise.
[Figure 3]
Figure 3
Hydro­gen-bonded chains in the crystal structure of (II[link]). Successive supermol­ecules are approximately perpendicular to each other; this view is perpendicular to (001).
[Figure 4]
Figure 4
Hydro­gen-bonded chains in the crystal structure of (II[link]). View of the chain, showing the atom numbering; view approximately along [010].
[Figure 5]
Figure 5
Packing of hydrogen-bonded chains in the crystal structure of (II[link]), forming a layer perpendicular to b*. Neighbouring chains are distributed along the c axis. Different chains (as shown in Figs. 2[link]–4[link][link]) are shown in different colours. This view is along a, cf. Fig. 2[link].
[Figure 6]
Figure 6
Packing of hydrogen-bonded chains in the crystal structure of (II[link]), forming a layer perpendicular to b*. As Fig. 5[link], but with the green mol­ecule deleted to reveal C—H⋯O hydrogen bonds formed between the blue and red chains shown in Fig. 5[link]. C—H⋯O hydrogen bonds within chains are shown in turquoise, those between chains are shown in magenta.
[Figure 7]
Figure 7
Packing of hydrogen-bonded chains in the crystal structure of (II[link]), forming a layer perpendicular to [010]. Neighbouring chains are connected by π-stacking interactions. This figure shows two chains viewed along [001]. One chain is shown in ball-and-stick representation, the other as wireframe.
[Figure 8]
Figure 8
Full packing diagram of the crystal structure of (II[link]), viewed along [100]. Different layers (as shown in Figs. 5[link]–7[link][link]) are shown in the top and bottom halves of the figure. C—H⋯O hydrogen bonds connect the layers.

Experimental

All materials were obtained from Aldrich and used as received. Isonicotin­amide (0.50 g, 4.10 mmol) was dissolved in an excess of propionic acid (2.40 g, 32.43 mmol) and warmed until all the solid dissolved. The solution was cooled to room temperature, producing colourless laths.

Crystal data
  • C6H6N2O·2C3H6O2

  • Mr = 270.28

  • Triclinic, [P\overline 1]

  • a = 10.038 (3) Å

  • b = 11.559 (4) Å

  • c = 12.740 (4) Å

  • α = 103.203 (6)°

  • β = 90.140 (6)°

  • γ = 102.247 (6)°

  • V = 1404.5 (8) Å3

  • Z = 4

  • Dx = 1.278 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 1107 reflections

  • θ = 2.6–22.2°

  • μ = 0.10 mm−1

  • T = 150 (2) K

  • Lath, colourless

  • 0.75 × 0.20 × 0.08 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer with an Oxford Cryosystems low-temperature device (Cosier & Glazer, 1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.])

  • φ and ω scans

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2004[Sheldrick, G. M. (2004). SADABS. University of Göttingen, Germany.]) Tmin = 0.783, Tmax = 1.000

  • 12519 measured reflections

  • 6498 independent reflections

  • 3362 reflections with I > 2σ(I)

  • Rint = 0.044

  • θmax = 28.9°

  • h = −13 → 13

  • k = −15 → 15

  • l = −17 → 17

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.088

  • wR(F2) = 0.198

  • S = 1.04

  • 6498 reflections

  • 379 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • w = 1/[σ2(Fo2) + (0.0681P)2 + 0.3798P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max < 0.001

  • Δρmax = 0.36 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bonding geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O3S—H3S⋯O8A 0.79 (4) 1.86 (4) 2.639 (4) 170 (4)
O3T—H3T⋯O8B 0.76 (5) 1.89 (5) 2.639 (4) 169 (5)
O3U—H3U⋯N1Bi 0.87 (4) 1.78 (4) 2.649 (4) 177 (5)
O3V—H3V⋯N1Aii 0.87 (5) 1.79 (5) 2.657 (4) 174 (5)
N9A—H91A⋯O2S 0.96 (5) 1.92 (4) 2.868 (4) 170 (5)
N9B—H91B⋯O2T 0.93 (4) 1.96 (4) 2.880 (4) 168 (3)
N9A—H92A⋯O2Uiii 0.92 (3) 2.02 (3) 2.901 (4) 161 (3)
N9B—H92B⋯O2V 0.93 (3) 2.01 (3) 2.900 (4) 160 (3)
C2A—H2A⋯O3Tiv 0.95 2.50 3.267 (5) 138
C2B—H2B⋯O3Sv 0.95 2.51 3.281 (5) 138
C5A—H5A⋯O2Uiii 0.95 2.40 3.328 (4) 167
C5B—H5B⋯O2V 0.95 2.39 3.322 (4) 168
C6A—H6A⋯O2Vvi 0.95 2.73 3.348 (4) 123
C6B—H6B⋯O2Ui 0.95 2.72 3.333 (4) 123
C4T—H4T1⋯O2Tvii 0.99 2.58 3.513 (5) 157
C4V—H4V1⋯O2Sviii 0.99 2.57 3.551 (4) 170
Symmetry codes: (i) 1-x,2-y,-z; (ii) 1+x,1+y,z-1; (iii) 1-x,1-y,1-z; (iv) x-1,y-1,z; (v) x,1+y,z; (vi) x-1,y-1,1+z; (vii) 2-x,1-y,-z; (viii) x,y,z-1.

H atoms were placed on C atoms in calculated positions [Uiso(H) = 1.2Ueq(C)] and allowed to ride on their parent atoms [C(phenyl)—H = 0.95, C(methylene)—H = 0.99 and C(methyl)—H = 0.98 Å]. Amide and hydroxyl H atoms were located in difference maps and refined freely, the former subject to the restraint N—H = 0.95 (3) Å. The ranges of N—H and O—H bond lengths were 0.91 (2)–0.96 (1) and 0.75 (5)–0.87 (4) Å, respectively.

Data collection: SMART (Bruker, 2001[Bruker (2001). SMART. Version 5.624. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2003[Bruker (2003). SAINT. Version 7. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT ; program(s) used to solve structure: SHELXTL (Sheldrick, 2001[Sheldrick, G. M. (2001). SHELXTL. Version 6.01. University of Göttingen, Germany.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL, MERCURY (Taylor & Macrae, 2001[Taylor, R. & Macrae, C. F. (2001). Acta Cryst. B57, 815-827.]) and DIAMOND (Crystal Impact, 2004[Crystal Impact (2004). DIAMOND. Version 3.0a. Crystal Impact GbR, Postfach 1251, 53002 Bonn, Germany. (URL: http://www.crystalimpact.com/diamond.)]); software used to prepare material for publication: SHELXTL, EnCIFer (Allen et al., 2004[Allen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst. 37, 335-338.]) and PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]), as incorporated in WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.])..

Supporting information


Comment top

Isonicotinamide has been shown to crystallize with carboxylic acids in a 1:1 stoichiometry to form a robust building block or `supermolecule' consisting of two amide and two acid molecules, (I) (Aakeröy et al., 2002). When a saturated solution of isonicotinamide in warm propionic acid was allowed to cool, colourless crystalline laths were obtained. Single-crystal X-ray diffraction revealed these to be a co-crystal consisting of isonicotinamide and propionic acid in a 1:2 ratio, viz. (II). Similar preparative routes with formic and acetic acids both yielded 1:1 co-crystals (Oswald et al., 2004). Attempts to prepare a 1:1 co-crystal with priopionic acid failed. For example, a 1:1 mixture of propionic acid and isonicotinamide in ethanol yielded only crystals of (II); even in the presence of isonicotinamide excess, the only crystals obtained were isonicotinamide itself and (II).

The crystal structure of (II) consists of supermolecules comprising two acid and one isonicotinamide molecule. One acid forms an R22(8) motif with the amide moiety (Bernstein et al., 1995). Another acid molecule forms a hydrogen bond to the pyridine N atom, supported by a weaker C–H···O hydrogen bond (Fig. 1 and Table 1). There are two supermolecules in the asymmetric unit and, in the terminology of Aakeröy et al. (2002), both are in the trans–trans conformation.

The independent supermolecules hydrogen-bond together using the second amide donor and the carbonyl group from the propionic acid molecules located at the pyridine end of the supermolecules. This builds-up a helical chain in which successive supermolecules are aligned approximately perpendicular to one another (Figs. 2–4; hydrogen-bond dimensions are listed in Table 1). The chains run along the [100] direction, and they comprise all the conventional N—H···O and O—H···O hydrogen bonds in the crystal (see Table 1); additional C–H···O interactions (C5A—H5A···O2U and C5B—H5B···O2V) are also formed within the chains (Desiraju & Steiner, 1999).

Successive helical chains are distributed along the c direction at z = 1/4, 3/4···, etc. (Fig. 5). Though there are no direct hydrogen-bonding interactions between neighbouring chains, weak C—H···O interactions are formed between chains located one lattice-repeat away from each other (e.g. the red and blue chains in Fig. 5; see also Fig. 6). These interactions involve C2A—H2A···O3T and C2B—H2B···O3S. Supermolecules in neighbouring chains are interleaved to produce stacks of supermolecules along [100] (Fig 5). Stacks containing only the supermolecules based on isonicotinamide molecule A occur at z = 1/2, while stacks containing only those based on molecule B occur at z = 0, 1,··· etc. Within the stacks pairs of pyridine moieties are π-stacked across inversion centres (Fig 7). The stacking distances are 3.34 and 3.33 Å for the A and B pyridine rings, respectively.

Thus, layers are formed in the ac-plane by chains of hydrogen-bonded supermolecules linked by weak C—H···O and π-stacking interactions. The layers are connected via C—H···O hydrogen bonds involving pairs of C4T—H4T1···O2T and C4V—H4V1···O2S interactions disposed about inversion centres (Fig. 8).

Experimental top

All materials were obtained from Aldrich and used as received. Isonicotinamide (0.50 g, 4.10 mmol) was dissolved in an excess of propionic acid (2.40 g, 32.43 mmol) and warmed until all the solid dissolved. The solution was cooled to room temperature, producing colourless laths.

Refinement top

X-ray diffraction intensities were collected on a Bruker SMART APEX CCD diffractometer equipped with an Oxford Cryosystems low-temperature device (Cosier & Glazer, 1986). H atoms were placed on C atoms in calculated positions [Uiso(H) = 1.2Ueq(C)] and allowed to ride on their parent atoms. Amide and hydroxyl H atoms were located in difference maps and refined freely, the former subject to the restraint N—H = 0.95 (3) Å. The ranges of N—H and O—H bond lengths were 0.91 (2)–0.96 (1) and 0.75 (5)–0.87 (4) Å, respectively.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SMART; data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXTL (Sheldrick, 2001); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL, Mercury (Taylor & Macrae, 2001) and DIAMOND (Crystal Impact, 2004); software used to prepare material for publication: SHELXTL, enCIFer (Allen et al., 2004) and PLATON (Spek, 2004), as incorported in WinGX (Farrugia, 1999)..

Figures top
[Figure 1] Fig. 1. The two crystallographically independent supermolecules,with the atomic numbering. Probability ellipsoids enclose 30% probability surfaces. Conventional hydrogen bonds are shown in heavy dashes and the H···O distances span 1.78 (4)–1.96 (4) Å (see table 1). The C—H···O hydrogen bonds (shown as open dashes) quite weak for this type of interaction (2.73 and 2.72 Å).
[Figure 2] Fig. 2. Hydrogen-bonded chains in the crystal structure of (II). Hydrogen bonds link supermolecules into chains. This view is appoximately along the direct lattice direction [100]. Hydrogen bonds are shown as dashed lines, weak C—H···O hydrogen bonds are shown in turquoise.
[Figure 3] Fig. 3. Hydrogen-bonded chains in the crystal structure of (II). Successive supermolecules are approximately perpendicular to each other; this view is along the reciprocal lattice direction (001).
[Figure 4] Fig. 4. Hydrogen-bonded chains in the crystal structure of (II). View of the chain, showing the atom numbering; view approximately along (010).
[Figure 5] Fig. 5. Packing of hydrogen-bonded chains in the crystal structure of (II), forming a layer perpendicular to (010). Neighbouring chains are distributed along the c axis. Different chains (as shown in Figs. 2–4) are shown in different colours. This view is along [100], cf. Fig. 2.
[Figure 6] Fig. 6. Packing of hydrogen-bonded chains in the crystal structure of (II), forming a layer perpendicular to (010). As Fig. 5, but with the green molecule deleted to reveal C—H···O hydrogen bonds formed between the blue and red chains shown in Fig. 5. C—H···O hydrogen bonds within chains are shown in turquoise, those between chains are shown in magenta.
[Figure 7] Fig. 7. Packing of hydrogen-bonded chains in the crystal structure of (II), forming a layer perpendicular to (010). Neighbouring chains are connected by π-stacking interactions. This figure shows two chains viewed along (001). One chain is shown as balls-and-sticks, the other as wireframe.
[Figure 8] Fig. 8. Full packing diagram of the crystal structure of (II), viewed along [100]. Different layers (as shown in Figs. 5–7) are shown in the top and bottom halves of the figure. C—H···O hydrogen bonds connect the layers.
Isonicotinamide–propionic acid (1:2) top
Crystal data top
C6H6N2O·2C3H6O2Z = 4
Mr = 270.28F(000) = 576
Triclinic, P1Dx = 1.278 Mg m3
Hall symbol: -P1Mo Kα radiation, λ = 0.71073 Å
a = 10.038 (3) ÅCell parameters from 1107 reflections
b = 11.559 (4) Åθ = 2.6–22.2°
c = 12.740 (4) ŵ = 0.10 mm1
α = 103.203 (6)°T = 150 K
β = 90.140 (6)°Lath, colourless
γ = 102.247 (6)°0.75 × 0.20 × 0.08 mm
V = 1404.5 (8) Å3
Data collection top
Bruker SMART CCD area-detector
diffractometer
6498 independent reflections
Radiation source: fine-focus sealed tube3362 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.044
ϕ and ω scansθmax = 28.9°, θmin = 1.6°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)
h = 1313
Tmin = 0.783, Tmax = 1.000k = 1515
12519 measured reflectionsl = 1717
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.088Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.198H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.0681P)2 + 0.3798P]
where P = (Fo2 + 2Fc2)/3
6498 reflections(Δ/σ)max < 0.001
379 parametersΔρmax = 0.36 e Å3
4 restraintsΔρmin = 0.21 e Å3
Crystal data top
C6H6N2O·2C3H6O2γ = 102.247 (6)°
Mr = 270.28V = 1404.5 (8) Å3
Triclinic, P1Z = 4
a = 10.038 (3) ÅMo Kα radiation
b = 11.559 (4) ŵ = 0.10 mm1
c = 12.740 (4) ÅT = 150 K
α = 103.203 (6)°0.75 × 0.20 × 0.08 mm
β = 90.140 (6)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
6498 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)
3362 reflections with I > 2σ(I)
Tmin = 0.783, Tmax = 1.000Rint = 0.044
12519 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0884 restraints
wR(F2) = 0.198H atoms treated by a mixture of independent and constrained refinement
S = 1.04Δρmax = 0.36 e Å3
6498 reflectionsΔρmin = 0.21 e Å3
379 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. ABSTM02_ALERT_3_C The ratio of expected to reported Tmax/Tmin(RR') is < 0.90 PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large ············. 0.84 T min and Tmax reported: 0.783 1.000 Tmin' and Tmax expected: 0.927 0.992 Noted, but no action taken. SADABS attempts to correct for all systematic errors not just absorption. The large range could represent a small amount of crystal decay for example.

PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low ······. 0.98

============================================================================

Resolution & Completeness Statistics (Cumulative) ============================================================================

Theta sin(th)/Lambda Complete Expected Measured Missing —————————————————————————- —- 20.82 0.500 0.998 2939 2932 7 23.01 0.550 0.990 3900 3861 39 25.24 0.600 0.979 5085 4978 107 ———————————————————— ACTA Min. Res. —- 27.51 0.650 0.961 6447 6198 249 29.84 0.700 0.875 7427 6498 929

PLAT063_ALERT_3_C Crystal Probably too Large for Beam Size ······. 0.75 mm

Gorbitz has shown that use of a large crystal does not appear to matter. See C. H. Gorbitz Acta Cryst. (1999). B55, 1090–1098

PLAT414_ALERT_2_C Short Intra D—H.·H—X H5A.. H92A.. 1.98 A ng PLAT414_ALERT_2_C Short Intra D—H.·H—X H5B.. H92B.. 1.96 A ng PLAT480_ALERT_4_C Long H···A H-Bond Reported H6A.. O2V.. 2.73 A ng PLAT480_ALERT_4_C Long H···A H-Bond Reported H6B.. O2U.. 2.72 A ng

See text.

PLAT222_ALERT_3_C Large Non-Solvent H Ueq(max)/Ueq(min) ··· 3.02 Ratio PLAT340_ALERT_3_C Low Bond Precision on C—C bonds (x 1000) Ang ··· 5 PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ······.. 20 PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd. # 4 C3 H6 O2

PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd. # 6 C3 H6 O2

No action taken.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N1A0.0374 (3)0.1364 (2)0.5184 (2)0.0340 (6)
C2A0.0899 (3)0.1354 (3)0.4224 (3)0.0399 (9)
H2A0.04240.18990.35980.048*
C3A0.2125 (3)0.0566 (3)0.4114 (3)0.0367 (8)
H3A0.24820.05760.34230.044*
C4A0.2807 (3)0.0225 (3)0.5023 (2)0.0307 (7)
C5A0.2266 (3)0.0211 (3)0.6018 (3)0.0358 (8)
H5A0.27240.07390.66590.043*
C6A0.1023 (3)0.0605 (3)0.6056 (3)0.0372 (8)
H6A0.06350.06100.67340.045*
C7A0.4134 (3)0.1076 (3)0.4875 (3)0.0300 (7)
O8A0.4515 (2)0.1028 (2)0.39475 (18)0.0422 (6)
N9A0.4801 (3)0.1821 (3)0.5743 (2)0.0400 (7)
H91A0.559 (4)0.239 (4)0.561 (4)0.13 (2)*
H92A0.448 (4)0.177 (4)0.641 (2)0.075 (14)*
N1B0.6050 (2)1.1345 (2)0.0179 (2)0.0347 (7)
C2B0.6559 (3)1.1321 (3)0.0769 (3)0.0363 (8)
H2B0.63521.18650.13960.044*
C3B0.7394 (3)1.0525 (3)0.0886 (3)0.0372 (8)
H3B0.77381.05210.15800.045*
C4B0.7705 (3)0.9749 (3)0.0022 (2)0.0318 (8)
C5B0.7187 (3)0.9781 (3)0.1016 (3)0.0343 (8)
H5B0.73950.92620.16580.041*
C6B0.6340 (3)1.0601 (3)0.1058 (3)0.0358 (8)
H6B0.59671.06200.17380.043*
C7B0.8617 (3)0.8898 (3)0.0125 (3)0.0315 (8)
O8B0.9029 (2)0.8942 (2)0.10510 (18)0.0435 (6)
N9B0.8926 (3)0.8168 (3)0.0743 (2)0.0402 (7)
H91B0.943 (4)0.761 (3)0.064 (3)0.079 (14)*
H92B0.855 (3)0.817 (3)0.141 (2)0.059 (11)*
C1S0.7475 (3)0.3193 (3)0.4192 (3)0.0380 (8)
O2S0.7115 (3)0.3378 (2)0.5096 (2)0.0546 (7)
O3S0.6802 (3)0.2306 (2)0.34051 (19)0.0442 (7)
H3S0.618 (4)0.189 (3)0.361 (3)0.052 (13)*
C4S0.8744 (4)0.3943 (3)0.3861 (3)0.0473 (9)
H4S10.86450.47990.40130.057*
H4S20.95190.39160.43290.057*
C5S0.9112 (4)0.3599 (4)0.2720 (3)0.0597 (11)
H5S10.92490.27630.25580.090*
H5S20.99550.41550.26110.090*
H5S30.83740.36520.22410.090*
C1T1.0981 (3)0.6806 (3)0.0803 (3)0.0374 (8)
O2T1.0571 (2)0.6652 (2)0.0116 (2)0.0521 (7)
O3T1.0671 (3)0.7648 (3)0.1601 (2)0.0468 (7)
H3T1.029 (5)0.809 (4)0.145 (4)0.10 (2)*
C4T1.1877 (4)0.6048 (3)0.1135 (3)0.0468 (9)
H4T11.13690.51890.09550.056*
H4T21.26860.60990.06910.056*
C5T1.2363 (4)0.6365 (4)0.2284 (3)0.0621 (12)
H5T11.28720.72140.24800.093*
H5T21.29600.58290.23950.093*
H5T31.15790.62630.27360.093*
C1U0.5951 (3)0.7137 (3)0.1200 (3)0.0331 (8)
O2U0.5695 (2)0.7875 (2)0.19782 (18)0.0417 (6)
O3U0.5494 (3)0.7069 (2)0.02220 (19)0.0440 (6)
H3U0.496 (4)0.757 (4)0.021 (3)0.086 (16)*
C4U0.6782 (3)0.6226 (3)0.1251 (3)0.0442 (9)
H4U10.75070.62910.07300.053*
H4U20.61910.54000.10260.053*
C5U0.7439 (4)0.6374 (4)0.2361 (3)0.0574 (11)
H5U10.80060.71980.26020.086*
H5U20.80100.57770.23260.086*
H5U30.67270.62430.28730.086*
C1V0.7618 (3)0.7141 (3)0.3789 (3)0.0319 (8)
O2V0.8246 (2)0.7852 (2)0.30190 (18)0.0417 (6)
O3V0.8021 (3)0.7075 (2)0.47843 (18)0.0410 (6)
H3V0.876 (5)0.763 (4)0.479 (4)0.11 (2)*
C4V0.6318 (3)0.6233 (3)0.3745 (3)0.0419 (9)
H4V10.64850.54010.39850.050*
H4V20.56210.63220.42540.050*
C5V0.5763 (4)0.6378 (4)0.2626 (3)0.0572 (11)
H5V10.64430.62830.21180.086*
H5V20.49250.57560.26450.086*
H5V30.55610.71890.23930.086*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N1A0.0336 (15)0.0404 (17)0.0301 (16)0.0147 (13)0.0006 (12)0.0068 (13)
C2A0.044 (2)0.048 (2)0.0270 (19)0.0148 (18)0.0026 (15)0.0027 (16)
C3A0.039 (2)0.043 (2)0.0292 (19)0.0145 (16)0.0062 (15)0.0059 (16)
C4A0.0311 (18)0.0397 (19)0.0268 (18)0.0192 (15)0.0031 (14)0.0082 (15)
C5A0.040 (2)0.041 (2)0.0266 (18)0.0118 (16)0.0037 (14)0.0062 (15)
C6A0.038 (2)0.051 (2)0.0258 (18)0.0168 (17)0.0034 (15)0.0081 (16)
C7A0.0331 (18)0.0347 (19)0.0273 (18)0.0168 (15)0.0033 (14)0.0086 (15)
O8A0.0419 (14)0.0506 (15)0.0308 (14)0.0072 (11)0.0074 (11)0.0053 (11)
N9A0.0385 (18)0.053 (2)0.0293 (17)0.0112 (15)0.0020 (14)0.0098 (15)
N1B0.0327 (15)0.0389 (17)0.0283 (16)0.0003 (12)0.0036 (12)0.0066 (13)
C2B0.0356 (19)0.042 (2)0.0260 (18)0.0049 (16)0.0013 (14)0.0008 (15)
C3B0.0333 (19)0.045 (2)0.0300 (19)0.0028 (16)0.0016 (14)0.0074 (16)
C4B0.0247 (17)0.0384 (19)0.0256 (18)0.0044 (14)0.0012 (13)0.0041 (15)
C5B0.0316 (18)0.041 (2)0.0261 (18)0.0027 (15)0.0051 (14)0.0039 (15)
C6B0.0305 (18)0.047 (2)0.0277 (19)0.0027 (16)0.0031 (14)0.0097 (16)
C7B0.0240 (17)0.040 (2)0.0267 (18)0.0002 (14)0.0046 (14)0.0058 (15)
O8B0.0443 (14)0.0561 (16)0.0298 (14)0.0148 (12)0.0054 (11)0.0060 (12)
N9B0.0369 (17)0.057 (2)0.0296 (17)0.0164 (15)0.0024 (13)0.0105 (15)
C1S0.037 (2)0.036 (2)0.041 (2)0.0110 (16)0.0024 (17)0.0075 (17)
O2S0.0603 (17)0.0601 (18)0.0367 (16)0.0011 (13)0.0122 (13)0.0086 (13)
O3S0.0406 (15)0.0520 (17)0.0380 (16)0.0037 (13)0.0121 (12)0.0123 (14)
C4S0.048 (2)0.046 (2)0.048 (2)0.0055 (18)0.0052 (18)0.0144 (19)
C5S0.051 (2)0.051 (3)0.068 (3)0.001 (2)0.015 (2)0.007 (2)
C1T0.0295 (18)0.038 (2)0.044 (2)0.0010 (15)0.0086 (16)0.0140 (18)
O2T0.0605 (17)0.0616 (17)0.0381 (16)0.0204 (13)0.0049 (13)0.0128 (13)
O3T0.0473 (16)0.0573 (18)0.0402 (16)0.0202 (14)0.0039 (12)0.0122 (14)
C4T0.041 (2)0.053 (2)0.048 (2)0.0085 (18)0.0012 (17)0.0167 (19)
C5T0.071 (3)0.062 (3)0.055 (3)0.027 (2)0.011 (2)0.005 (2)
C1U0.0280 (17)0.038 (2)0.032 (2)0.0005 (15)0.0009 (14)0.0135 (16)
O2U0.0442 (14)0.0499 (15)0.0316 (14)0.0156 (12)0.0041 (11)0.0058 (12)
O3U0.0492 (15)0.0549 (17)0.0311 (14)0.0223 (14)0.0019 (11)0.0066 (12)
C4U0.043 (2)0.044 (2)0.050 (2)0.0134 (17)0.0062 (17)0.0182 (18)
C5U0.055 (3)0.055 (3)0.069 (3)0.018 (2)0.008 (2)0.023 (2)
C1V0.0361 (19)0.038 (2)0.0297 (19)0.0199 (16)0.0084 (15)0.0135 (16)
O2V0.0384 (13)0.0551 (16)0.0276 (14)0.0075 (12)0.0012 (11)0.0042 (12)
O3V0.0427 (15)0.0500 (16)0.0279 (13)0.0070 (13)0.0062 (11)0.0070 (11)
C4V0.041 (2)0.039 (2)0.048 (2)0.0101 (17)0.0103 (16)0.0142 (17)
C5V0.051 (2)0.059 (3)0.064 (3)0.010 (2)0.023 (2)0.022 (2)
Geometric parameters (Å, º) top
N1A—C6A1.318 (4)C4S—H4S10.9900
N1A—C2A1.333 (4)C4S—H4S20.9900
C2A—C3A1.396 (5)C5S—H5S10.9800
C2A—H2A0.9500C5S—H5S20.9800
C3A—C4A1.375 (4)C5S—H5S30.9800
C3A—H3A0.9500C1T—O2T1.201 (4)
C4A—C5A1.383 (4)C1T—O3T1.325 (4)
C4A—C7A1.519 (4)C1T—C4T1.502 (5)
C5A—C6A1.404 (4)O3T—H3T0.75 (5)
C5A—H5A0.9500C4T—C5T1.479 (5)
C6A—H6A0.9500C4T—H4T10.9900
C7A—O8A1.235 (4)C4T—H4T20.9900
C7A—N9A1.315 (4)C5T—H5T10.9800
N9A—H91A0.96 (3)C5T—H5T20.9800
N9A—H92A0.91 (2)C5T—H5T30.9800
N1B—C2B1.318 (4)C1U—O2U1.218 (4)
N1B—C6B1.321 (4)C1U—O3U1.307 (4)
C2B—C3B1.401 (4)C1U—C4U1.488 (5)
C2B—H2B0.9500O3U—H3U0.87 (4)
C3B—C4B1.375 (4)C4U—C5U1.517 (5)
C3B—H3B0.9500C4U—H4U10.9900
C4B—C5B1.378 (4)C4U—H4U20.9900
C4B—C7B1.518 (4)C5U—H5U10.9800
C5B—C6B1.411 (4)C5U—H5U20.9800
C5B—H5B0.9500C5U—H5U30.9800
C6B—H6B0.9500C1V—O2V1.201 (4)
C7B—O8B1.236 (4)C1V—O3V1.323 (4)
C7B—N9B1.310 (4)C1V—C4V1.502 (4)
N9B—H91B0.93 (2)O3V—H3V0.87 (5)
N9B—H92B0.93 (2)C4V—C5V1.518 (5)
C1S—O2S1.194 (4)C4V—H4V10.9900
C1S—O3S1.321 (4)C4V—H4V20.9900
C1S—C4S1.501 (5)C5V—H5V10.9800
O3S—H3S0.79 (4)C5V—H5V20.9800
C4S—C5S1.485 (5)C5V—H5V30.9800
C6A—N1A—C2A119.4 (3)C4S—C5S—H5S1109.5
N1A—C2A—C3A121.9 (3)C4S—C5S—H5S2109.5
N1A—C2A—H2A119.1H5S1—C5S—H5S2109.5
C3A—C2A—H2A119.1C4S—C5S—H5S3109.5
C4A—C3A—C2A118.9 (3)H5S1—C5S—H5S3109.5
C4A—C3A—H3A120.5H5S2—C5S—H5S3109.5
C2A—C3A—H3A120.5O2T—C1T—O3T122.7 (3)
C3A—C4A—C5A119.2 (3)O2T—C1T—C4T122.4 (3)
C3A—C4A—C7A117.6 (3)O3T—C1T—C4T114.9 (3)
C5A—C4A—C7A123.2 (3)C1T—O3T—H3T117 (4)
C4A—C5A—C6A118.2 (3)C5T—C4T—C1T117.1 (3)
C4A—C5A—H5A120.9C5T—C4T—H4T1108.0
C6A—C5A—H5A120.9C1T—C4T—H4T1108.0
N1A—C6A—C5A122.4 (3)C5T—C4T—H4T2108.0
N1A—C6A—H6A118.8C1T—C4T—H4T2108.0
C5A—C6A—H6A118.8H4T1—C4T—H4T2107.3
O8A—C7A—N9A124.2 (3)C4T—C5T—H5T1109.5
O8A—C7A—C4A118.0 (3)C4T—C5T—H5T2109.5
N9A—C7A—C4A117.8 (3)H5T1—C5T—H5T2109.5
C7A—N9A—H91A115 (3)C4T—C5T—H5T3109.5
C7A—N9A—H92A119 (3)H5T1—C5T—H5T3109.5
H91A—N9A—H92A126 (4)H5T2—C5T—H5T3109.5
C2B—N1B—C6B119.4 (3)O2U—C1U—O3U122.0 (3)
N1B—C2B—C3B122.4 (3)O2U—C1U—C4U124.7 (3)
N1B—C2B—H2B118.8O3U—C1U—C4U113.2 (3)
C3B—C2B—H2B118.8C1U—O3U—H3U112 (3)
C4B—C3B—C2B118.7 (3)C1U—C4U—C5U113.9 (3)
C4B—C3B—H3B120.6C1U—C4U—H4U1108.8
C2B—C3B—H3B120.6C5U—C4U—H4U1108.8
C3B—C4B—C5B118.9 (3)C1U—C4U—H4U2108.8
C3B—C4B—C7B117.8 (3)C5U—C4U—H4U2108.8
C5B—C4B—C7B123.3 (3)H4U1—C4U—H4U2107.7
C4B—C5B—C6B118.6 (3)C4U—C5U—H5U1109.5
C4B—C5B—H5B120.7C4U—C5U—H5U2109.5
C6B—C5B—H5B120.7H5U1—C5U—H5U2109.5
N1B—C6B—C5B121.9 (3)C4U—C5U—H5U3109.5
N1B—C6B—H6B119.0H5U1—C5U—H5U3109.5
C5B—C6B—H6B119.0H5U2—C5U—H5U3109.5
O8B—C7B—N9B124.1 (3)O2V—C1V—O3V122.6 (3)
O8B—C7B—C4B118.2 (3)O2V—C1V—C4V125.0 (3)
N9B—C7B—C4B117.7 (3)O3V—C1V—C4V112.5 (3)
C7B—N9B—H91B117 (3)C1V—O3V—H3V110 (3)
C7B—N9B—H92B119 (2)C1V—C4V—C5V113.2 (3)
H91B—N9B—H92B123 (3)C1V—C4V—H4V1108.9
O2S—C1S—O3S122.9 (3)C5V—C4V—H4V1108.9
O2S—C1S—C4S122.5 (3)C1V—C4V—H4V2108.9
O3S—C1S—C4S114.5 (3)C5V—C4V—H4V2108.9
C1S—O3S—H3S112 (3)H4V1—C4V—H4V2107.7
C5S—C4S—C1S117.6 (3)C4V—C5V—H5V1109.5
C5S—C4S—H4S1107.9C4V—C5V—H5V2109.5
C1S—C4S—H4S1107.9H5V1—C5V—H5V2109.5
C5S—C4S—H4S2107.9C4V—C5V—H5V3109.5
C1S—C4S—H4S2107.9H5V1—C5V—H5V3109.5
H4S1—C4S—H4S2107.2H5V2—C5V—H5V3109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3S—H3S···O8A0.79 (4)1.86 (4)2.639 (4)170 (4)
O3T—H3T···O8B0.76 (5)1.89 (5)2.639 (4)169 (5)
O3U—H3U···N1Bi0.87 (4)1.78 (4)2.649 (4)177 (5)
O3V—H3V···N1Aii0.87 (5)1.79 (5)2.657 (4)174 (5)
N9A—H91A···O2S0.96 (5)1.92 (4)2.868 (4)170 (5)
N9B—H91B···O2T0.93 (4)1.96 (4)2.880 (4)168 (3)
N9A—H92A···O2Uiii0.92 (3)2.02 (3)2.901 (4)161 (3)
N9B—H92B···O2V0.93 (3)2.01 (3)2.900 (4)160 (3)
C2A—H2A···O3Tiv0.952.503.267 (5)138
C2B—H2B···O3Sv0.952.513.281 (5)138
C5A—H5A···O2Uiii0.952.403.328 (4)167
C5B—H5B···O2V0.952.393.322 (4)168
C6A—H6A···O2Vvi0.952.733.348 (4)123
C6B—H6B···O2Ui0.952.723.333 (4)123
C4T—H4T1···O2Tvii0.992.583.513 (5)157
C4V—H4V1···O2Sviii0.992.573.551 (4)170
Symmetry codes: (i) x+1, y+2, z; (ii) x+1, y+1, z1; (iii) x+1, y+1, z+1; (iv) x1, y1, z; (v) x, y+1, z; (vi) x1, y1, z+1; (vii) x+2, y+1, z; (viii) x, y, z1.

Experimental details

Crystal data
Chemical formulaC6H6N2O·2C3H6O2
Mr270.28
Crystal system, space groupTriclinic, P1
Temperature (K)150
a, b, c (Å)10.038 (3), 11.559 (4), 12.740 (4)
α, β, γ (°)103.203 (6), 90.140 (6), 102.247 (6)
V3)1404.5 (8)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.75 × 0.20 × 0.08
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2004)
Tmin, Tmax0.783, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
12519, 6498, 3362
Rint0.044
(sin θ/λ)max1)0.680
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.088, 0.198, 1.04
No. of reflections6498
No. of parameters379
No. of restraints4
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.36, 0.21

Computer programs: SMART (Bruker, 2001), SMART, SAINT (Bruker, 2003), SHELXTL (Sheldrick, 2001), SHELXTL, Mercury (Taylor & Macrae, 2001) and DIAMOND (Crystal Impact, 2004), SHELXTL, enCIFer (Allen et al., 2004) and PLATON (Spek, 2004), as incorported in WinGX (Farrugia, 1999)..

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3S—H3S···O8A0.79 (4)1.86 (4)2.639 (4)170 (4)
O3T—H3T···O8B0.76 (5)1.89 (5)2.639 (4)169 (5)
O3U—H3U···N1Bi0.87 (4)1.78 (4)2.649 (4)177 (5)
O3V—H3V···N1Aii0.87 (5)1.79 (5)2.657 (4)174 (5)
N9A—H91A···O2S0.96 (5)1.92 (4)2.868 (4)170 (5)
N9B—H91B···O2T0.93 (4)1.96 (4)2.880 (4)168 (3)
N9A—H92A···O2Uiii0.92 (3)2.02 (3)2.901 (4)161 (3)
N9B—H92B···O2V0.93 (3)2.01 (3)2.900 (4)160 (3)
C2A—H2A···O3Tiv0.952.503.267 (5)138
C2B—H2B···O3Sv0.952.513.281 (5)138
C5A—H5A···O2Uiii0.952.403.328 (4)167
C5B—H5B···O2V0.952.393.322 (4)168
C6A—H6A···O2Vvi0.952.733.348 (4)123
C6B—H6B···O2Ui0.952.723.333 (4)123
C4T—H4T1···O2Tvii0.992.583.513 (5)157
C4V—H4V1···O2Sviii0.992.573.551 (4)170
Symmetry codes: (i) x+1, y+2, z; (ii) x+1, y+1, z1; (iii) x+1, y+1, z+1; (iv) x1, y1, z; (v) x, y+1, z; (vi) x1, y1, z+1; (vii) x+2, y+1, z; (viii) x, y, z1.
 

Acknowledgements

We thank the EPSRC, the University of Edinburgh and the Cambridge Crystallographic Data Centre for funding.

References

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