Creatininium dipicolinate monohydrate

The title compound, (creatH)⁺(pydcH)⁻·H₂O or C₄H₈N₃O⁺·C₇H₄NO₄⁻·H₂O, was obtained by the reaction of 2,6-pyridine­di­carboxyl­ic acid (dipicolinic acid, pydcH₂) with creatinine (creat). A single proton from the di­carboxyl­ic acid is transferred to the endocyclic imine N atom of creatinine. The cations and anions lie on a crystallographic mirror plane, across which the water mol­ecule is disordered. The interactions among cations, anions and water mol­ecules consist of ion-pairing, hydrogen bonding and π–π stacking.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.048
• wR factor = 0.162
• Data-to-parameter ratio = 22.3

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT417_ALERT_2_B Short Inter D-H..H-D       H1W    ..  H2W     ..       1.63 Ang.

Alert level C
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT128_ALERT_4_C Non-standard setting of Space group Pnma    ....    Pnam
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.65
PLAT301_ALERT_3_C Main Residue  Disorder .........................       2.00 Perc.
PLAT417_ALERT_2_C Short Inter D-H..H-D       H2W    ..  H2N4    ..       2.11 Ang.
PLAT417_ALERT_2_C Short Inter D-H..H-D       H2W    ..  H2N4    ..       2.11 Ang.
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........          4

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

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

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Computing details

Data collection: CAD4 (Enraf-Nonius, 1984); cell refinement: CAD-4 Software (Enraf-Nonius, 1984); data reduction: XCAD4 (Harms, 1996); program(s) used to solve structure: SHELXTL (Sheldrick, 1998); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

(I)

Crystal data

C4H8N3O^+·C7H4NO4^−·H2O	Dx = 1.493 Mg m^−3
Mr = 298.26	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pnam	Cell parameters from 24 reflections
a = 13.485 (3) Å	θ = 10–11°
b = 15.107 (3) Å	µ = 0.12 mm^−1
c = 6.5150 (13) Å	T = 293 K
V = 1327.2 (5) Å^3	Block, colorless
Z = 4	0.45 × 0.30 × 0.25 mm
F(000) = 624

Data collection

Enraf-Nonius CAD-4 diffractometer	Rint = 0.013
Radiation source: fine-focus sealed tube	θmax = 34.0°, θmin = 2.0°
Graphite monochromator	h = 0→21
θ–θ scans	k = 0→23
3012 measured reflections	l = 0→10
2898 independent reflections	3 standard reflections every 97 reflections
1603 reflections with I > 2σ(I)	intensity decay: 2.5%

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.048	Hydrogen site location: geom and difmap
wR(F^2) = 0.162	H-atom parameters constrained
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0896P)^2 + 0.0618P] where P = (Fo^2 + 2Fc^2)/3
2898 reflections	(Δ/σ)max < 0.001
130 parameters	Δρmax = 0.39 e Å^−3
0 restraints	Δρmin = −0.29 e Å^−3

Special details

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

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

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
C1	0.09689 (11)	0.41937 (12)	0.2500	0.0299 (4)
O1	0.43871 (10)	0.44580 (11)	0.2500	0.0560 (5)
O2	0.37232 (10)	0.31205 (10)	0.2500	0.0467 (4)
O3	0.02884 (9)	0.27545 (9)	0.2500	0.0431 (4)
H1O3	−0.0289	0.2369	0.2500	0.052*
O4	−0.07581 (9)	0.38924 (11)	0.2500	0.0482 (4)
O5	0.91100 (11)	0.65500 (11)	0.2500	0.0505 (4)
N1	0.18733 (9)	0.38221 (9)	0.2500	0.0274 (3)
N2	0.65486 (11)	0.62312 (11)	0.2500	0.0370 (4)
N3	0.79273 (11)	0.54497 (10)	0.2500	0.0329 (3)
H1N3	0.8254	0.4993	0.2500	0.039*
N4	0.64137 (11)	0.46844 (11)	0.2500	0.0387 (4)
H2N4	0.6772	0.4142	0.2500	0.046*
H1N4	0.5712	0.4714	0.2500	0.046*
C2	0.08199 (13)	0.50963 (13)	0.2500	0.0423 (5)
H2A	0.0181	0.5329	0.2500	0.051*
C3	0.16321 (15)	0.56460 (13)	0.2500	0.0464 (6)
H3A	0.1552	0.6257	0.2500	0.056*
C4	0.25624 (14)	0.52809 (12)	0.2500	0.0367 (4)
H4A	0.3123	0.5639	0.2500	0.044*
C5	0.26502 (11)	0.43632 (11)	0.2500	0.0277 (3)
C6	0.36790 (12)	0.39522 (12)	0.2500	0.0308 (4)
C7	0.00823 (12)	0.35870 (13)	0.2500	0.0337 (4)
C8	0.69129 (12)	0.54208 (12)	0.2500	0.0302 (4)
C9	0.82597 (14)	0.63143 (12)	0.2500	0.0354 (4)
C10	0.73403 (14)	0.68813 (12)	0.2500	0.0386 (4)
H10	0.7301	0.7312	0.1321	0.046*
C11	0.55006 (15)	0.64668 (16)	0.2500	0.0447 (5)
H11A	0.5149	0.6109	0.1478	0.067*	0.50
H11B	0.5298	0.7066	0.1612	0.067*	0.50
H11C	0.5311	0.6605	0.3869	0.067*	0.50
O1W	0.72297 (15)	0.31002 (12)	0.1810 (4)	0.0588 (9)	0.50
H1W	0.7928	0.3073	0.2500	0.071*
H2W	0.6783	0.2751	0.2811	0.071*	0.50

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0207 (6)	0.0283 (8)	0.0408 (10)	−0.0002 (5)	0.000	0.000
O1	0.0206 (6)	0.0465 (9)	0.1008 (14)	−0.0054 (5)	0.000	0.000
O2	0.0246 (6)	0.0333 (7)	0.0821 (11)	0.0067 (5)	0.000	0.000
O3	0.0253 (5)	0.0304 (6)	0.0735 (11)	−0.0062 (5)	0.000	0.000
O4	0.0200 (5)	0.0444 (8)	0.0801 (11)	0.0001 (5)	0.000	0.000
O5	0.0312 (7)	0.0453 (8)	0.0749 (11)	−0.0059 (6)	0.000	0.000
N1	0.0192 (5)	0.0259 (6)	0.0371 (8)	−0.0013 (5)	0.000	0.000
N2	0.0254 (6)	0.0303 (7)	0.0553 (11)	0.0055 (5)	0.000	0.000
N3	0.0241 (6)	0.0270 (7)	0.0475 (9)	0.0033 (5)	0.000	0.000
N4	0.0264 (7)	0.0324 (8)	0.0573 (11)	0.0009 (5)	0.000	0.000
C2	0.0232 (7)	0.0318 (9)	0.0720 (15)	0.0039 (6)	0.000	0.000
C3	0.0343 (9)	0.0232 (8)	0.0815 (17)	0.0017 (7)	0.000	0.000
C4	0.0305 (8)	0.0243 (7)	0.0553 (12)	−0.0043 (6)	0.000	0.000
C5	0.0195 (6)	0.0271 (7)	0.0364 (9)	−0.0012 (5)	0.000	0.000
C6	0.0216 (6)	0.0309 (8)	0.0399 (10)	0.0008 (6)	0.000	0.000
C7	0.0219 (7)	0.0353 (9)	0.0439 (10)	−0.0012 (6)	0.000	0.000
C8	0.0244 (7)	0.0318 (8)	0.0344 (9)	0.0035 (6)	0.000	0.000
C9	0.0304 (8)	0.0329 (9)	0.0430 (11)	−0.0010 (7)	0.000	0.000
C10	0.0343 (9)	0.0278 (8)	0.0538 (12)	0.0016 (7)	0.000	0.000
C11	0.0295 (8)	0.0500 (12)	0.0546 (13)	0.0139 (8)	0.000	0.000
O1W	0.0417 (10)	0.0333 (9)	0.101 (3)	0.0012 (8)	0.0021 (11)	0.0030 (11)

Geometric parameters (Å, º)

C1—N1	1.342 (2)	N4—H2N4	0.951
C1—C2	1.378 (3)	N4—H1N4	0.948
C1—C7	1.507 (2)	C2—C3	1.375 (3)
O1—C6	1.223 (2)	C2—H2A	0.930
O2—C6	1.258 (2)	C3—C4	1.370 (3)
O3—C7	1.288 (2)	C3—H3A	0.930
O3—H1O3	0.973	C4—C5	1.391 (2)
O4—C7	1.224 (2)	C4—H4A	0.930
O5—C9	1.201 (2)	C5—C6	1.520 (2)
N1—C5	1.329 (2)	C9—C10	1.507 (3)
N2—C8	1.319 (2)	C10—H10	1.007
N2—C10	1.451 (2)	C11—H11A	0.9806
N2—C11	1.457 (3)	C11—H11B	1.108
N3—C8	1.369 (2)	C11—H11C	0.951
N3—C9	1.381 (2)	O1W—H1W	1.042
N3—H1N3	0.819	O1W—H2W	1.032
N4—C8	1.300 (2)
N1—C1—C2	123.10 (15)	C4—C5—C6	118.99 (14)
N1—C1—C7	117.81 (15)	O1—C6—O2	125.95 (17)
C2—C1—C7	119.08 (15)	O1—C6—C5	117.22 (17)
C7—O3—H1O3	114.3	O2—C6—C5	116.83 (14)
C5—N1—C1	117.33 (14)	O4—C7—O3	124.61 (17)
C8—N2—C10	110.75 (14)	O4—C7—C1	120.38 (18)
C8—N2—C11	126.00 (17)	O3—C7—C1	115.01 (14)
C10—N2—C11	123.26 (16)	N4—C8—N2	126.96 (16)
C8—N3—C9	110.76 (15)	N4—C8—N3	123.00 (16)
C8—N3—H1N3	120.7	N2—C8—N3	110.04 (16)
C9—N3—H1N3	128.5	O5—C9—N3	126.19 (17)
C8—N4—H2N4	118.3	O5—C9—C10	128.11 (17)
C8—N4—H1N4	118.5	N3—C9—C10	105.70 (15)
H2N4—N4—H1N4	123.2	N2—C10—C9	102.75 (15)
C3—C2—C1	118.78 (16)	N2—C10—H10	113.4
C3—C2—H2A	120.6	C9—C10—H10	114.2
C1—C2—H2A	120.6	N2—C11—H11A	109.5
C4—C3—C2	119.10 (17)	N2—C11—H11B	116.0
C4—C3—H3A	120.5	H11A—C11—H11B	88.6
C2—C3—H3A	120.5	N2—C11—H11C	108.3
C3—C4—C5	118.62 (16)	H11A—C11—H11C	129.0
C3—C4—H4A	120.7	H11B—C11—H11C	104.1
C5—C4—H4A	120.7	O1W^i—O1W—H1W	64.7
N1—C5—C4	123.08 (15)	O1W^i—O1W—H2W	50.8
N1—C5—C6	117.93 (15)	H1W—O1W—H2W	103.7
C2—C1—N1—C5	0.0	C2—C1—C7—O4	0.0
C7—C1—N1—C5	180.0	N1—C1—C7—O3	0.0
N1—C1—C2—C3	0.0	C2—C1—C7—O3	180.0
C7—C1—C2—C3	180.0	C10—N2—C8—N4	180.0
C1—C2—C3—C4	0.0	C11—N2—C8—N4	0.0
C2—C3—C4—C5	0.0	C10—N2—C8—N3	0.0
C1—N1—C5—C4	0.0	C11—N2—C8—N3	180.0
C1—N1—C5—C6	180.0	C9—N3—C8—N4	180.0
C3—C4—C5—N1	0.0	C9—N3—C8—N2	0.0
C3—C4—C5—C6	180.0	C8—N3—C9—O5	180.0
N1—C5—C6—O1	180.0	C8—N3—C9—C10	0.0
C4—C5—C6—O1	0.0	C8—N2—C10—C9	0.0
N1—C5—C6—O2	0.0	C11—N2—C10—C9	180.0
C4—C5—C6—O2	180.0	O5—C9—C10—N2	180.0
N1—C1—C7—O4	180.0	N3—C9—C10—N2	0.0

Symmetry code: (i) x, y, −z+1/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H1O3···O2^ii	0.97	1.52	2.490 (2)	172
N3—H1N3···O4^iii	0.82	2.13	2.946 (2)	174
N4—H2N4···O1W	0.95	1.75	2.672 (3)	163
N4—H2N4···O1W^i	0.95	1.75	2.672 (3)	163
N4—H1N4···O1	0.95	1.83	2.754 (2)	165
O1W—H1W···O2^iv	1.04	2.10	2.768 (2)	120
O1W—H1W···O4^iii	1.04	2.16	2.999 (3)	136
O1W—H2W···O3^iv	1.03	2.17	2.953 (2)	132
O1W—H2W···N1^iv	1.03	2.39	2.978 (3)	115

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