5-Amino-8-(1-amino­ethyl­idene)-8H-tetrazolo­[1,5-a]­pyridin-7-one dihydrate

The title compound, C₇H₈N₆O·2H₂O, contains a tetrazole ring fused to a substituted pyridone ring. Bond lengths correspond to delocalized π electrons in the tetrazole moiety and a push–pull effect in the pyridone ring. An extended network of hydrogen bonds connects the mol­ecules in planes parallel to the bc plane, while the water mol­ecules form chains parallel to the a axis.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.051
• wR factor = 0.124
• Data-to-parameter ratio = 9.8

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT111_ALERT_2_B ADDSYM Detects (Pseudo) Centre of Symmetry .....         93 PerFit

Alert level C
PLAT031_ALERT_4_C Refined Extinction Parameter within Range ......       3.00 Sigma
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT222_ALERT_3_C Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       3.36 Ratio

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           29.99
           From the CIF: _reflns_number_total               1789
           Count of symmetry unique reflns         1788
           Completeness (_total/calc)            100.06%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         1
           Fraction of Friedel pairs measured     0.001
           Are heavy atom types Z>Si present           no

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

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 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
   2 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: XSCANS (Siemens, 1994); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXS97 (Sheldrick,1997); program(s) used to refine structure: SHELXL97 (Sheldrick,1997); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: PLATON (Spek, 1998).

5-Amino-8-(1-aminoethylidene)-8H-tetrazolo[1,5-a]pyridin-7-one dihydrate

Crystal data

C7H8N6O·2H2O	Dx = 1.434 Mg m^−3
Mr = 228.23	Melting point: 568 K
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 42 reflections
a = 6.751 (1) Å	θ = 4–38°
b = 11.990 (1) Å	µ = 0.12 mm^−1
c = 13.061 (1) Å	T = 293 K
V = 1057.2 (2) Å^3	Plate, colourless
Z = 4	0.3 × 0.2 × 0.1 mm
F(000) = 480

Data collection

Siemens P4 diffractometer	Rint = 0.032
Radiation source: sealed tube	θmax = 30.0°, θmin = 2.3°
Graphite monochromator	h = −9→9
ω scans	k = −16→16
3578 measured reflections	l = −18→18
1789 independent reflections	3 standard reflections every 97 reflections
1049 reflections with I > 2σ(I)	intensity decay: no decay

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F^2 > 2σ(F^2)] = 0.051	w = 1/[σ^2(Fo^2) + (0.0575P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.124	(Δ/σ)max < 0.001
S = 0.99	Δρmax = 0.21 e Å^−3
1789 reflections	Δρmin = −0.25 e Å^−3
182 parameters	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
6 restraints	Extinction coefficient: 0.0036 (12)
Primary atom site location: structure-invariant direct methods	Absolute structure: Friedel pairs have been merged before the refinement
Secondary atom site location: difference Fourier map

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
C1	0.9686 (6)	0.7686 (2)	0.9601 (2)	0.0333 (7)
C2	0.9689 (5)	0.8591 (2)	1.0304 (2)	0.0341 (7)
C4	0.9663 (6)	0.7339 (2)	1.1788 (2)	0.0348 (7)
C5	0.9694 (6)	0.6456 (2)	1.1142 (2)	0.0360 (7)
C6	0.9711 (5)	0.6571 (2)	1.0053 (2)	0.0346 (7)
C12	0.9676 (6)	0.7846 (2)	0.8528 (2)	0.0366 (7)
C13	0.9647 (7)	0.8968 (3)	0.8031 (2)	0.0483 (9)
H13A	0.9610	0.8881	0.7300	0.098 (16)*
H13B	1.0816	0.9374	0.8221	0.052 (11)*
H13C	0.8495	0.9371	0.8252	0.104 (17)*
N3	0.9658 (5)	0.83895 (17)	1.13309 (16)	0.0367 (6)
N7	0.9661 (5)	0.93700 (19)	1.18498 (18)	0.0515 (8)
N8	0.9688 (6)	1.01315 (18)	1.11538 (19)	0.0543 (8)
N9	0.9699 (5)	0.97058 (18)	1.01892 (18)	0.0452 (7)
N10	0.9620 (7)	0.7331 (2)	1.28145 (19)	0.0516 (9)
N14	0.9673 (6)	0.6976 (2)	0.7920 (2)	0.0496 (7)
O1	0.9743 (7)	0.36641 (19)	1.0375 (2)	0.0848 (12)
O2	1.0818 (5)	0.1794 (2)	0.92370 (19)	0.0705 (10)
O11	0.9743 (4)	0.57040 (15)	0.94936 (14)	0.0471 (6)
H2	0.992 (8)	0.122 (4)	0.950 (5)	0.148 (12)*
H2'	1.226 (5)	0.168 (5)	0.925 (5)	0.148 (12)*
H1	0.987 (10)	0.437 (3)	1.000 (4)	0.148 (12)*
H1'	1.010 (11)	0.308 (4)	0.988 (4)	0.148 (12)*
H10	0.974 (6)	0.665 (3)	1.312 (3)	0.054 (10)*
H10'	0.971 (6)	0.797 (3)	1.310 (2)	0.044 (9)*
H14	0.960 (6)	0.707 (3)	0.723 (3)	0.054 (10)*
H14'	0.951 (7)	0.631 (3)	0.825 (3)	0.077 (14)*
H5	0.974 (5)	0.572 (2)	1.137 (2)	0.031 (7)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0401 (18)	0.0287 (12)	0.0312 (13)	−0.0020 (15)	0.0007 (15)	−0.0002 (10)
C2	0.0408 (18)	0.0299 (12)	0.0316 (13)	−0.0031 (15)	−0.0002 (15)	0.0026 (10)
C4	0.0458 (19)	0.0261 (12)	0.0326 (14)	0.0007 (16)	0.0007 (17)	0.0055 (10)
C5	0.0463 (19)	0.0266 (13)	0.0352 (14)	−0.0008 (16)	−0.0006 (16)	0.0036 (10)
C6	0.0383 (17)	0.0316 (13)	0.0338 (13)	0.0020 (17)	−0.0006 (14)	0.0007 (11)
C12	0.0364 (16)	0.0408 (14)	0.0325 (13)	−0.0040 (17)	−0.0017 (15)	−0.0001 (12)
C13	0.061 (2)	0.0478 (17)	0.0361 (17)	0.000 (2)	−0.0019 (19)	0.0106 (14)
N3	0.0566 (17)	0.0250 (9)	0.0287 (10)	−0.0001 (15)	0.0018 (13)	−0.0016 (9)
N7	0.088 (2)	0.0283 (11)	0.0383 (13)	−0.0040 (17)	−0.0006 (18)	−0.0032 (10)
N8	0.093 (2)	0.0294 (11)	0.0406 (13)	0.0022 (17)	0.0014 (19)	0.0001 (10)
N9	0.0674 (19)	0.0285 (11)	0.0397 (13)	−0.0004 (16)	0.0019 (16)	0.0024 (10)
N10	0.092 (3)	0.0289 (12)	0.0339 (13)	0.0006 (18)	−0.0004 (19)	0.0035 (11)
N14	0.071 (2)	0.0471 (14)	0.0307 (13)	0.0004 (18)	−0.0007 (17)	−0.0004 (12)
O1	0.170 (4)	0.0402 (12)	0.0445 (13)	0.002 (2)	0.011 (2)	0.0062 (10)
O2	0.127 (3)	0.0435 (13)	0.0408 (12)	−0.0119 (18)	0.0039 (16)	0.0066 (11)
O11	0.0728 (15)	0.0294 (9)	0.0391 (11)	0.0003 (13)	−0.0004 (13)	−0.0047 (8)

Geometric parameters (Å, º)

C1—C12	1.415 (4)	C13—H13B	0.9600
C1—C2	1.421 (4)	C13—H13C	0.9600
C1—C6	1.461 (4)	N3—N7	1.357 (3)
C2—N9	1.345 (3)	N7—N8	1.289 (3)
C2—N3	1.363 (3)	N8—N9	1.359 (3)
C4—N10	1.342 (4)	N10—H10	0.92 (3)
C4—C5	1.353 (4)	N10—H10'	0.86 (3)
C4—N3	1.393 (3)	N14—H14	0.91 (4)
C5—C6	1.430 (4)	N14—H14'	0.92 (4)
C5—H5	0.94 (3)	O1—H1	0.98 (3)
C6—O11	1.270 (3)	O1—H1'	0.98 (3)
C12—N14	1.311 (4)	O2—H2	0.98 (3)
C12—C13	1.494 (4)	O2—H2'	0.98 (3)
C13—H13A	0.9600
C12—C1—C2	122.4 (2)	C12—C13—H13B	109.5
C12—C1—C6	121.6 (2)	H13A—C13—H13B	109.5
C2—C1—C6	116.0 (2)	C12—C13—H13C	109.5
N9—C2—N3	106.6 (2)	H13A—C13—H13C	109.5
N9—C2—C1	133.4 (3)	H13B—C13—H13C	109.5
N3—C2—C1	120.0 (2)	N7—N3—C2	109.8 (2)
N10—C4—C5	128.1 (2)	N7—N3—C4	124.7 (2)
N10—C4—N3	115.8 (2)	C2—N3—C4	125.5 (2)
C5—C4—N3	116.1 (2)	N8—N7—N3	105.2 (2)
C4—C5—C6	123.0 (2)	N7—N8—N9	112.8 (2)
C4—C5—H5	123.0 (16)	C2—N9—N8	105.7 (2)
C6—C5—H5	114.0 (16)	C4—N10—H10	116 (2)
O11—C6—C5	119.6 (2)	C4—N10—H10'	115 (2)
O11—C6—C1	121.1 (2)	H10—N10—H10'	127 (3)
C5—C6—C1	119.3 (2)	C12—N14—H14	120 (2)
N14—C12—C1	119.4 (3)	C12—N14—H14'	114 (2)
N14—C12—C13	117.0 (3)	H14—N14—H14'	125 (3)
C1—C12—C13	123.6 (2)	H1—O1—H1'	105 (4)
C12—C13—H13A	109.5	H2—O2—H2'	121 (5)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···N9^i	0.98 (3)	2.04 (5)	2.896 (4)	146 (5)
O2—H2′···O1^ii	0.98 (3)	1.80 (4)	2.753 (6)	164 (5)
O1—H1···O11	0.98 (3)	1.73 (4)	2.703 (3)	169 (6)
O1—H1′···O2	0.98 (3)	1.82 (3)	2.786 (4)	166 (5)
N10—H10···N8^iii	0.92 (3)	2.09 (4)	2.998 (3)	174 (4)
N10—H10′···O1^iv	0.86 (3)	2.19 (3)	2.886 (4)	139 (3)
N14—H14···O2^v	0.91 (4)	1.96 (4)	2.845 (4)	162 (3)
N14—H14′···O11	0.92 (4)	1.78 (4)	2.560 (4)	141 (4)

Symmetry codes: (i) x, y−1, z; (ii) x+1/2, −y+1/2, −z+2; (iii) −x+2, y−1/2, −z+5/2; (iv) −x+2, y+1/2, −z+5/2; (v) −x+2, y+1/2, −z+3/2.