Diethyl 1H-pyrazole-3,5-di­carboxyl­ate

The crystal structure of the title compound, C₉H₁₂N₂O₄, has been determined in the monoclinic space group P2₁/c. There are two mol­ecules in the asymmetric unit and the two pyrazole rings are almost coplanar. The two mol­ecules have different conformations and are connected into a dimer via intermolecular N—H...O and N—H...N hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.047
• wR factor = 0.113
• Data-to-parameter ratio = 14.2

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT026_ALERT_3_B Ratio Observed / Unique Reflections too Low ....         37 Perc.
PLAT230_ALERT_2_B Hirshfeld Test Diff for    N1A    -   C3A      =       7.37 su
PLAT230_ALERT_2_B Hirshfeld Test Diff for    C7A    -   C9A      =       7.18 su

Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C1     -   C5       =       5.51 su
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C1A    -   C5A      =       5.30 su
PLAT241_ALERT_2_C Check High   U(eq) as Compared to Neighbors ....        C7A
PLAT250_ALERT_2_C Large U3/U1 ratio for average U(i,j) tensor ....       2.20
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) ........         10

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

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

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Computing details

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2000); software used to prepare material for publication: SHELXTL.

diethyl 1H-pyrazole-3,5-dicarboxylate

Crystal data

C9H12N2O4	F(000) = 896
Mr = 212.21	Dx = 1.274 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 10969 reflections
a = 9.184 (2) Å	θ = 2.3–18.9°
b = 14.147 (3) Å	µ = 0.10 mm^−1
c = 17.302 (4) Å	T = 298 K
β = 100.074 (4)°	Plate, colorless
V = 2213.2 (9) Å^3	0.30 × 0.30 × 0.10 mm
Z = 8

Data collection

Bruker CCD area-detector diffractometer	3892 independent reflections
Radiation source: fine-focus sealed tube	1424 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.061
Detector resolution: 100x100 microns pixels mm^-1	θmax = 25.0°, θmin = 1.9°
ω scans	h = −10→10
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	k = −16→8
Tmin = 0.970, Tmax = 0.990	l = −20→20
8965 measured reflections

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)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.113	H-atom parameters constrained
S = 0.81	w = 1/[σ^2(Fo^2) + (0.0355P)^2] where P = (Fo^2 + 2Fc^2)/3
3892 reflections	(Δ/σ)max < 0.001
275 parameters	Δρmax = 0.13 e Å^−3
0 restraints	Δρmin = −0.14 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
C1	0.7758 (3)	−0.0228 (2)	1.01133 (18)	0.0622 (9)
C2	0.8780 (3)	0.0310 (3)	1.06195 (16)	0.0718 (10)
H2	0.9572	0.0089	1.0984	0.086*
C3	0.8380 (3)	0.1227 (2)	1.04693 (17)	0.0610 (9)
C4	0.9032 (4)	0.2123 (3)	1.0782 (2)	0.0747 (10)
C5	0.7705 (4)	−0.1262 (3)	1.0022 (2)	0.0763 (10)
C6	0.6497 (5)	−0.2555 (2)	0.9319 (2)	0.1155 (15)
H6A	0.7331	−0.2749	0.9081	0.139*
H6B	0.6534	−0.2905	0.9804	0.139*
C7	0.8840 (4)	0.3794 (3)	1.0605 (2)	0.1091 (13)
H7A	0.9811	0.3878	1.0468	0.131*
H7B	0.8920	0.3895	1.1166	0.131*
C8	0.5132 (4)	−0.2761 (2)	0.8792 (2)	0.1225 (15)
H8A	0.4311	−0.2625	0.9050	0.184*
H8B	0.5113	−0.3416	0.8648	0.184*
H8C	0.5066	−0.2377	0.8330	0.184*
C9	0.7794 (5)	0.4477 (2)	1.0173 (2)	0.1277 (15)
H9A	0.7724	0.4375	0.9619	0.192*
H9B	0.8139	0.5108	1.0301	0.192*
H9C	0.6838	0.4394	1.0315	0.192*
C3A	0.3519 (3)	0.1182 (2)	0.81126 (17)	0.0593 (9)
C2A	0.2389 (3)	0.0890 (2)	0.75479 (17)	0.0635 (9)
H2A	0.1706	0.1267	0.7227	0.076*
C1A	0.2469 (3)	−0.0094 (2)	0.75520 (17)	0.0582 (9)
C5A	0.1485 (4)	−0.0754 (3)	0.7058 (2)	0.0724 (10)
C4A	0.4034 (4)	0.2114 (2)	0.8398 (2)	0.0682 (10)
C7A	0.3693 (4)	0.3759 (2)	0.8193 (2)	0.1231 (16)
H7AB	0.3461	0.3918	0.8703	0.148*
H7AA	0.4749	0.3832	0.8215	0.148*
C6A	0.0935 (4)	−0.2352 (2)	0.67429 (19)	0.0958 (12)
H6AB	0.0910	−0.2263	0.6185	0.115*
H6AA	−0.0066	−0.2301	0.6847	0.115*
C9A	0.2894 (4)	0.4376 (2)	0.7598 (2)	0.1259 (15)
H9AC	0.3096	0.4195	0.7092	0.189*
H9AB	0.3204	0.5017	0.7707	0.189*
H9AA	0.1852	0.4323	0.7599	0.189*
C8A	0.1558 (4)	−0.3284 (2)	0.69901 (19)	0.1012 (13)
H8AC	0.2558	−0.3318	0.6900	0.152*
H8AB	0.0978	−0.3768	0.6693	0.152*
H8AA	0.1543	−0.3373	0.7539	0.152*
N1	0.7163 (3)	0.11955 (18)	0.99052 (14)	0.0737 (8)
H1	0.6694	0.1692	0.9713	0.088*
N2	0.6757 (3)	0.0320 (2)	0.96746 (14)	0.0707 (8)
N1A	0.4208 (2)	0.03840 (18)	0.84241 (13)	0.0661 (7)
H1A	0.4961	0.0387	0.8797	0.079*
N2A	0.3595 (3)	−0.04034 (17)	0.80916 (14)	0.0640 (7)
O1	1.0071 (3)	0.21917 (16)	1.13033 (14)	0.1070 (9)
O2	0.8301 (2)	0.28430 (17)	1.04012 (12)	0.0828 (7)
O3	0.8591 (3)	−0.17770 (16)	1.03982 (14)	0.1139 (10)
O4	0.6586 (2)	−0.15467 (15)	0.94832 (13)	0.0871 (7)
O3A	0.0442 (3)	−0.05032 (15)	0.65884 (14)	0.1060 (9)
O4A	0.1879 (2)	−0.16459 (16)	0.71888 (11)	0.0813 (7)
O1A	0.5046 (3)	0.22635 (13)	0.89249 (14)	0.0943 (8)
O2A	0.3247 (2)	0.27832 (15)	0.79859 (12)	0.0838 (7)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.062 (2)	0.061 (2)	0.062 (2)	0.007 (2)	0.0064 (18)	0.0056 (19)
C2	0.064 (2)	0.086 (3)	0.060 (2)	0.006 (2)	−0.0049 (18)	0.001 (2)
C3	0.053 (2)	0.071 (3)	0.057 (2)	−0.003 (2)	0.0045 (17)	−0.004 (2)
C4	0.062 (3)	0.087 (3)	0.073 (3)	0.000 (2)	0.006 (2)	−0.014 (2)
C5	0.075 (3)	0.080 (3)	0.070 (3)	0.010 (2)	0.003 (2)	0.010 (2)
C6	0.128 (4)	0.063 (3)	0.150 (4)	0.000 (3)	0.008 (3)	−0.017 (2)
C7	0.119 (4)	0.084 (3)	0.120 (3)	−0.032 (3)	0.008 (3)	−0.023 (3)
C8	0.111 (4)	0.093 (3)	0.162 (4)	−0.022 (3)	0.020 (3)	−0.028 (3)
C9	0.159 (4)	0.082 (3)	0.138 (4)	−0.006 (3)	0.014 (3)	0.000 (3)
C3A	0.061 (2)	0.043 (2)	0.071 (2)	0.0078 (18)	0.0022 (18)	0.0083 (18)
C2A	0.061 (2)	0.055 (2)	0.071 (2)	0.0039 (18)	0.0014 (18)	0.0065 (17)
C1A	0.054 (2)	0.054 (2)	0.064 (2)	−0.0021 (17)	0.0024 (17)	0.0006 (17)
C5A	0.065 (3)	0.064 (3)	0.082 (3)	0.006 (2)	−0.003 (2)	0.009 (2)
C4A	0.066 (3)	0.052 (2)	0.084 (3)	0.009 (2)	0.005 (2)	0.006 (2)
C7A	0.163 (4)	0.048 (3)	0.136 (4)	0.014 (3)	−0.036 (3)	0.001 (2)
C6A	0.099 (3)	0.064 (3)	0.108 (3)	−0.019 (2)	−0.024 (2)	−0.010 (2)
C9A	0.141 (4)	0.070 (3)	0.169 (4)	0.010 (3)	0.034 (3)	0.023 (3)
C8A	0.118 (3)	0.060 (2)	0.118 (3)	−0.009 (2)	−0.002 (2)	−0.009 (2)
N1	0.069 (2)	0.0594 (19)	0.085 (2)	0.0052 (15)	−0.0077 (16)	−0.0012 (15)
N2	0.072 (2)	0.0528 (18)	0.082 (2)	0.0027 (16)	0.0003 (15)	−0.0014 (16)
N1A	0.0608 (18)	0.0538 (18)	0.0764 (18)	−0.0041 (15)	−0.0082 (14)	−0.0042 (15)
N2A	0.0576 (17)	0.0519 (17)	0.0766 (18)	0.0009 (14)	−0.0041 (14)	−0.0003 (14)
O1	0.091 (2)	0.119 (2)	0.097 (2)	−0.0117 (16)	−0.0241 (16)	−0.0195 (15)
O2	0.0805 (18)	0.0724 (18)	0.0882 (17)	−0.0106 (14)	−0.0051 (13)	−0.0128 (14)
O3	0.124 (2)	0.0881 (19)	0.111 (2)	0.0321 (16)	−0.0297 (17)	0.0097 (15)
O4	0.0850 (18)	0.0652 (17)	0.1024 (18)	0.0043 (13)	−0.0077 (15)	−0.0030 (14)
O3A	0.100 (2)	0.0739 (17)	0.122 (2)	0.0020 (14)	−0.0406 (16)	0.0094 (14)
O4A	0.0810 (17)	0.0550 (15)	0.0945 (17)	−0.0008 (13)	−0.0220 (13)	0.0000 (13)
O1A	0.0913 (19)	0.0624 (16)	0.112 (2)	0.0020 (13)	−0.0285 (15)	−0.0023 (13)
O2A	0.0896 (18)	0.0497 (16)	0.1030 (18)	0.0067 (13)	−0.0080 (14)	0.0039 (13)

Geometric parameters (Å, º)

N1—N2	1.335 (3)	C7A—C9A	1.447 (4)
C1—N2	1.333 (3)	C6A—C8A	1.470 (4)
C1—C2	1.393 (4)	N1A—H1A	0.8600
C2—C3	1.361 (3)	C6—H6A	0.9700
C3—N1	1.349 (3)	C6—H6B	0.9700
C3—C4	1.464 (4)	C7—H7A	0.9700
C1—C5	1.470 (4)	C7—H7B	0.9700
C4—O1	1.197 (3)	C8—H8A	0.9600
C4—O2	1.330 (3)	C8—H8B	0.9600
C5—O3	1.197 (3)	C8—H8C	0.9600
C5—O4	1.324 (3)	C9—H9A	0.9600
C6—O4	1.454 (3)	C9—H9B	0.9600
C7—O2	1.456 (3)	C9—H9C	0.9600
C6—C8	1.444 (4)	C2A—H2A	0.9300
C7—C9	1.471 (4)	C7A—O2A	1.467 (3)
N1A—N2A	1.332 (3)	C7A—H7AB	0.9700
C1A—N2A	1.340 (3)	C7A—H7AA	0.9700
C2A—C1A	1.394 (3)	C6A—H6AB	0.9700
C3A—C2A	1.359 (3)	C6A—H6AA	0.9700
C3A—N1A	1.359 (3)	C9A—H9AC	0.9600
C3A—C4A	1.457 (4)	C9A—H9AB	0.9600
C1A—C5A	1.466 (4)	C9A—H9AA	0.9600
C5A—O3A	1.197 (3)	C8A—H8AC	0.9600
C5A—O4A	1.321 (3)	C8A—H8AB	0.9600
C4A—O1A	1.201 (3)	C8A—H8AA	0.9600
C4A—O2A	1.322 (3)	C2—H2	0.9300
C6A—O4A	1.454 (3)	N1—H1	0.8600
C2—C3—C4	132.4 (3)	C3—N1—H1	123.2
C2—C1—C5	128.1 (3)	H6A—C6—H6B	108.2
O1—C4—O2	125.3 (3)	O2—C7—H7A	110.0
O1—C4—C3	124.7 (4)	C9—C7—H7A	110.0
O3—C5—O4	124.6 (4)	O2—C7—H7B	110.0
O2—C7—C9	108.7 (3)	C9—C7—H7B	110.0
O3—C5—C1	122.7 (4)	H7A—C7—H7B	108.3
N1—C3—C4	122.0 (3)	C6—C8—H8A	109.5
N2—C1—C5	120.7 (3)	C6—C8—H8B	109.5
N2—C1—C2	111.2 (3)	H8A—C8—H8B	109.5
C3—C2—C1	105.7 (3)	C6—C8—H8C	109.5
C4—O2—C7	117.9 (3)	H8A—C8—H8C	109.5
C5—O4—C6	116.5 (3)	H8B—C8—H8C	109.5
N2—N1—C3	113.6 (2)	C7—C9—H9A	109.5
C1—N2—N1	103.9 (3)	C7—C9—H9B	109.5
N1—C3—C2	105.6 (3)	H9A—C9—H9B	109.5
O2—C4—C3	110.0 (3)	C7—C9—H9C	109.5
O4—C5—C1	112.7 (3)	H9A—C9—H9C	109.5
C8—C6—O4	109.5 (3)	H9B—C9—H9C	109.5
C2A—C3A—C4A	132.9 (3)	C3A—C2A—H2A	127.3
C2A—C1A—C5A	127.4 (3)	C1A—C2A—H2A	127.3
O1A—C4A—C3A	125.4 (3)	C9A—C7A—H7AB	110.1
O3A—C5A—O4A	124.2 (3)	O2A—C7A—H7AB	110.1
O1A—C4A—O2A	124.1 (3)	C9A—C7A—H7AA	110.1
O3A—C5A—C1A	123.0 (3)	O2A—C7A—H7AA	110.1
N1A—C3A—C4A	121.1 (3)	H7AB—C7A—H7AA	108.4
C5A—O4A—C6A	116.5 (3)	O4A—C6A—H6AB	110.3
C4A—O2A—C7A	116.1 (3)	C8A—C6A—H6AB	110.3
N2A—C1A—C5A	121.3 (3)	O4A—C6A—H6AA	110.3
O4A—C6A—C8A	107.2 (3)	C8A—C6A—H6AA	110.3
C3A—C2A—C1A	105.5 (3)	H6AB—C6A—H6AA	108.5
N1A—C3A—C2A	106.1 (3)	C7A—C9A—H9AC	109.5
N2A—C1A—C2A	111.3 (3)	C7A—C9A—H9AB	109.5
O4A—C5A—C1A	112.7 (3)	H9AC—C9A—H9AB	109.5
O2A—C4A—C3A	110.5 (3)	C7A—C9A—H9AA	109.5
C9A—C7A—O2A	108.0 (3)	H9AC—C9A—H9AA	109.5
N2A—N1A—C3A	113.0 (2)	H9AB—C9A—H9AA	109.5
N1A—N2A—C1A	104.1 (2)	C6A—C8A—H8AC	109.5
C1—C2—H2	127.1	C6A—C8A—H8AB	109.5
C3—C2—H2	127.1	H8AC—C8A—H8AB	109.5
C8—C6—H6A	109.8	C6A—C8A—H8AA	109.5
O4—C6—H6A	109.8	H8AC—C8A—H8AA	109.5
C8—C6—H6B	109.8	H8AB—C8A—H8AA	109.5
O4—C6—H6B	109.8	N2A—N1A—H1A	123.5
N2—N1—H1	123.2	C3A—N1A—H1A	123.5
N2—C1—C2—C3	−0.7 (4)	C2A—C3A—C4A—O2A	−3.2 (5)
C5—C1—C2—C3	178.5 (3)	C2—C3—N1—N2	−0.6 (3)
C1—C2—C3—N1	0.8 (3)	C4—C3—N1—N2	177.9 (3)
C1—C2—C3—C4	−177.5 (3)	C2—C1—N2—N1	0.3 (3)
N1—C3—C4—O1	176.8 (3)	C5—C1—N2—N1	−178.9 (3)
C2—C3—C4—O1	−5.2 (6)	C3—N1—N2—C1	0.2 (3)
N1—C3—C4—O2	−3.3 (4)	C2A—C3A—N1A—N2A	0.4 (3)
C2—C3—C4—O2	174.7 (3)	C4A—C3A—N1A—N2A	−179.8 (3)
N2—C1—C5—O3	179.2 (3)	C3A—N1A—N2A—C1A	−0.4 (3)
C2—C1—C5—O3	0.1 (6)	C2A—C1A—N2A—N1A	0.3 (3)
N2—C1—C5—O4	−0.6 (4)	C5A—C1A—N2A—N1A	−179.0 (3)
C2—C1—C5—O4	−179.7 (3)	O1—C4—O2—C7	3.0 (5)
N1A—C3A—C2A—C1A	−0.2 (3)	C3—C4—O2—C7	−176.9 (3)
C4A—C3A—C2A—C1A	180.0 (3)	C9—C7—O2—C4	−174.6 (3)
C3A—C2A—C1A—N2A	−0.1 (4)	O3—C5—O4—C6	−3.4 (5)
C3A—C2A—C1A—C5A	179.2 (3)	C1—C5—O4—C6	176.4 (3)
N2A—C1A—C5A—O3A	177.6 (3)	C8—C6—O4—C5	173.2 (3)
C2A—C1A—C5A—O3A	−1.6 (5)	O3A—C5A—O4A—C6A	−2.2 (5)
N2A—C1A—C5A—O4A	−2.6 (4)	C1A—C5A—O4A—C6A	178.0 (3)
C2A—C1A—C5A—O4A	178.2 (3)	C8A—C6A—O4A—C5A	−178.9 (3)
N1A—C3A—C4A—O1A	−1.8 (5)	O1A—C4A—O2A—C7A	1.2 (5)
C2A—C3A—C4A—O1A	178.0 (4)	C3A—C4A—O2A—C7A	−177.6 (3)
N1A—C3A—C4A—O2A	176.9 (3)	C9A—C7A—O2A—C4A	169.9 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1A	0.86	2.02	2.790 (3)	149
N1A—H1A···N2	0.86	2.04	2.898 (3)	177