3-Chloro-6-(3,5-dimethyl-1H-pyrazol-1-yl)picolinic acid

In the title compound, C₁₁H₁₀ClN₃O₂, the dihedral angle between the two rings is 5.6°. The crystal structure is stabilized by O—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](Wav) = 0.000 Å
• R factor = 0.041
• wR factor = 0.114
• Data-to-parameter ratio = 13.2

checkCIF/PLATON results

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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           25.00
           From the CIF: _reflns_number_total               2038
           Count of symmetry unique reflns         1082
           Completeness (_total/calc)            188.35%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       956
           Fraction of Friedel pairs measured     0.884
           Are heavy atom types Z>Si present        yes

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

The chemical and pharmacological properties of pyrazoles have been investigated extensively, owing to their chelating ability with metal ions and to their potentially beneficial chemical and biological activities, (Elguero et al., 1984;), e.g; antitumor, antineoplastic,antibacterial and antimalarial (Liao et al.,2000; Fun et al.,1996; Lu et al.,1996). Recently we reported the 4-(3,5-dimethyl-1H-pyrazol-1-yl)phthalazin-1(2H)-one; (Kai et al., 2007). We report here the synthesis and crystal structure of 3-chloro-6-(3,5-dimethyl-1H-pyrazol-1-yl)picolinic acid. The C—N distances range from 1.332 (4) to 1.411 (3) Å, i.e. normal values. The C=O bond length is 1.231 (3) Å, indicating that the molecule is in the keto form.

In the crystal structure, the molecules are interconnected, by intermolecular O—H···O hydrogen bonds (Fig. 2; for symmetry codes see Table1).

Related literature

For related literature, see: Liao et al. (2000); Elguero et al. (1984); Fun et al. (1996); Lu et al. (1996); Kai et al. (2007).

S2. Experimental

A solution of 3-chloro-6-hydrazinylpicolinic acid(10 mmol) in 50 ml toluene was added to a solution of pentane-2,4-dione(10 mmol) in 10 ml toluene. The reaction mixture was refluxed for 1 h with stirring. then the resulting pale colorless precipitate was obtained by filtration, washed several times with ethanol and dried in vacuo (yield 90%). Analysis calculated for the title compound (C₁₁H₁₀ClN₃O₂): C, 52.40; H, 4.11; N, 16.60; O, 12.81; in the crystal, found: C, 52.50; H, 4.01; N, 16.70; O, 12.71. A me thanol solution of the title compound was slowly evaporated and colorless crystals were obtained after one week.

S3. Refinement

The positions of all H atoms were fixed geometrically and refined isotropically using a riding model. The bond lengths for C—H are in the range 0.93–0.96 Å, The bond lengths for N—H are 0.86 Å, respectively.

Data collection: Bruker SMART(Siemens, 1996); cell refinement: Bruker SMART(Siemens, 1996); data reduction: Bruker SAINT(Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: SHELXTL (Sheldrick, 1997b); software used to prepare material for publication: SHELXTL (Sheldrick, 1997b).

Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SMART (Siemens, 1996); data reduction: SAINT (Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: SHELXTL (Sheldrick, 1997b); software used to prepare material for publication: SHELXTL (Sheldrick, 1997b).

Figures

	Fig. 1. The structure of the title compound (I) showing 50% probability displacement ellipsoids and the atom-numbering scheme.
	Fig. 2. Crystal packing of (I) showing the hydrogen bonded interactions as dashed lines.
	Fig. 3. The formation of the title compound.

3-Chloro-6-(3,5-dimethyl-1H-pyrazol-1-yl)picolinic acid

Crystal data

C11H10ClN3O2	F(000) = 520
Mr = 251.67	Dx = 1.426 Mg m^−3
Orthorhombic, Pna21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2n	Cell parameters from 2331 reflections
a = 17.972 (2) Å	θ = 2.3–27.0°
b = 4.5618 (6) Å	µ = 0.32 mm^−1
c = 14.303 (2) Å	T = 298 K
V = 1172.6 (3) Å^3	Block, colorless
Z = 4	0.53 × 0.50 × 0.36 mm

Data collection

Bruker SMART CCD area-detector diffractometer	2038 independent reflections
Radiation source: fine-focus sealed tube	1806 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.041
phi and ω scans	θmax = 25.0°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −21→16
Tmin = 0.849, Tmax = 0.894	k = −3→5
4435 measured reflections	l = −17→16

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.041	H-atom parameters constrained
wR(F^2) = 0.114	w = 1/[σ^2(Fo^2) + (0.0709P)^2 + 0.0549P] where P = (Fo^2 + 2Fc^2)/3
S = 1.06	(Δ/σ)max < 0.001
2038 reflections	Δρmax = 0.25 e Å^−3
154 parameters	Δρmin = −0.24 e Å^−3
1 restraint	Absolute structure: Flack (1983), 956 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.03 (9)

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
Cl1	−0.15772 (4)	1.09661 (17)	0.51407 (7)	0.0586 (3)
N1	0.00189 (14)	0.5293 (6)	0.44703 (17)	0.0400 (6)
N2	0.09799 (11)	0.3047 (5)	0.52919 (16)	0.0376 (5)
N3	0.12733 (14)	0.2224 (6)	0.61406 (17)	0.0405 (6)
O1	−0.05743 (12)	0.7992 (6)	0.28282 (15)	0.0593 (6)
H1	−0.0786	0.7646	0.2332	0.089*
O2	−0.16318 (15)	0.6490 (8)	0.3462 (2)	0.0877 (11)
C1	−0.09889 (17)	0.7136 (8)	0.3518 (2)	0.0500 (8)
C2	−0.05762 (17)	0.7100 (7)	0.4443 (2)	0.0410 (7)
C3	−0.08141 (15)	0.8661 (6)	0.5207 (2)	0.0396 (6)
C4	−0.04237 (18)	0.8392 (7)	0.6036 (2)	0.0461 (8)
H4	−0.0570	0.9460	0.6559	0.055*
C5	0.01755 (17)	0.6565 (7)	0.6090 (2)	0.0414 (7)
H5	0.0442	0.6354	0.6643	0.050*
C6	0.03751 (14)	0.5019 (6)	0.5282 (2)	0.0361 (6)
C7	0.1212 (2)	0.2198 (11)	0.3557 (2)	0.0657 (10)
H7A	0.1556	0.1052	0.3197	0.099*
H7B	0.1269	0.4233	0.3402	0.099*
H7C	0.0713	0.1588	0.3417	0.099*
C8	0.13615 (16)	0.1764 (8)	0.4570 (2)	0.0418 (7)
C9	0.19019 (16)	0.0079 (7)	0.4978 (2)	0.0450 (7)
H9	0.2252	−0.1074	0.4671	0.054*
C10	0.18273 (18)	0.0425 (7)	0.5939 (2)	0.0431 (7)
C11	0.22903 (18)	−0.0922 (8)	0.6711 (3)	0.0571 (9)
H11A	0.2222	0.0176	0.7277	0.086*
H11B	0.2806	−0.0882	0.6536	0.086*
H11C	0.2137	−0.2914	0.6809	0.086*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0498 (4)	0.0487 (4)	0.0773 (6)	0.0094 (3)	0.0004 (4)	0.0100 (4)
N1	0.0391 (12)	0.0466 (13)	0.0342 (14)	−0.0025 (11)	−0.0008 (10)	0.0018 (12)
N2	0.0365 (12)	0.0461 (12)	0.0303 (12)	−0.0009 (10)	0.0001 (10)	0.0017 (12)
N3	0.0390 (13)	0.0494 (15)	0.0330 (13)	0.0017 (11)	−0.0002 (9)	0.0009 (12)
O1	0.0504 (13)	0.0890 (18)	0.0384 (12)	0.0002 (12)	−0.0020 (10)	0.0052 (12)
O2	0.0599 (16)	0.142 (3)	0.0611 (17)	−0.0352 (16)	−0.0180 (12)	0.0307 (18)
C1	0.048 (2)	0.054 (2)	0.0485 (19)	−0.0010 (15)	−0.0042 (14)	0.0097 (15)
C2	0.0392 (16)	0.0421 (16)	0.0416 (16)	−0.0075 (13)	−0.0031 (12)	0.0097 (14)
C3	0.0392 (13)	0.0344 (14)	0.0452 (16)	−0.0036 (11)	0.0002 (14)	0.0071 (14)
C4	0.0546 (19)	0.0421 (16)	0.0414 (18)	0.0020 (14)	0.0058 (14)	0.0003 (13)
C5	0.0486 (17)	0.0419 (15)	0.0336 (16)	−0.0007 (14)	−0.0038 (12)	−0.0001 (12)
C6	0.0395 (13)	0.0357 (13)	0.0331 (14)	−0.0068 (11)	0.0002 (12)	0.0038 (13)
C7	0.067 (2)	0.092 (3)	0.0384 (19)	0.015 (2)	0.0096 (16)	−0.0034 (18)
C8	0.0377 (15)	0.0524 (18)	0.0352 (16)	−0.0034 (14)	0.0059 (12)	−0.0008 (14)
C9	0.0348 (15)	0.0531 (18)	0.0472 (19)	0.0001 (13)	0.0069 (12)	−0.0063 (15)
C10	0.0376 (16)	0.0455 (16)	0.0462 (18)	−0.0023 (14)	0.0018 (13)	0.0018 (15)
C11	0.050 (2)	0.066 (2)	0.055 (2)	0.0165 (16)	−0.0034 (15)	−0.0003 (17)

Geometric parameters (Å, º)

Cl1—C3	1.731 (3)	C4—H4	0.9300
N1—C6	1.332 (4)	C5—C6	1.401 (4)
N1—C2	1.351 (4)	C5—H5	0.9300
N2—C8	1.371 (4)	C7—C8	1.487 (5)
N2—N3	1.376 (3)	C7—H7A	0.9600
N2—C6	1.411 (3)	C7—H7B	0.9600
N3—C10	1.322 (4)	C7—H7C	0.9600
O1—C1	1.297 (4)	C8—C9	1.369 (5)
O1—H1	0.8200	C9—C10	1.390 (5)
O2—C1	1.195 (4)	C9—H9	0.9300
C1—C2	1.516 (4)	C10—C11	1.513 (5)
C2—C3	1.374 (4)	C11—H11A	0.9600
C3—C4	1.383 (5)	C11—H11B	0.9600
C4—C5	1.364 (4)	C11—H11C	0.9600
C6—N1—C2	117.6 (3)	C5—C6—N2	120.7 (2)
C8—N2—N3	110.9 (2)	C8—C7—H7A	109.5
C8—N2—C6	130.5 (3)	C8—C7—H7B	109.5
N3—N2—C6	118.6 (2)	H7A—C7—H7B	109.5
C10—N3—N2	105.4 (2)	C8—C7—H7C	109.5
C1—O1—H1	109.5	H7A—C7—H7C	109.5
O2—C1—O1	125.4 (3)	H7B—C7—H7C	109.5
O2—C1—C2	121.9 (3)	C9—C8—N2	105.8 (3)
O1—C1—C2	112.7 (3)	C9—C8—C7	128.2 (3)
N1—C2—C3	122.6 (3)	N2—C8—C7	125.9 (3)
N1—C2—C1	114.8 (3)	C8—C9—C10	106.8 (3)
C3—C2—C1	122.5 (3)	C8—C9—H9	126.6
C2—C3—C4	118.6 (3)	C10—C9—H9	126.6
C2—C3—Cl1	121.2 (2)	N3—C10—C9	111.0 (3)
C4—C3—Cl1	120.2 (2)	N3—C10—C11	120.5 (3)
C5—C4—C3	120.2 (3)	C9—C10—C11	128.5 (3)
C5—C4—H4	119.9	C10—C11—H11A	109.5
C3—C4—H4	119.9	C10—C11—H11B	109.5
C4—C5—C6	117.6 (3)	H11A—C11—H11B	109.5
C4—C5—H5	121.2	C10—C11—H11C	109.5
C6—C5—H5	121.2	H11A—C11—H11C	109.5
N1—C6—C5	123.3 (3)	H11B—C11—H11C	109.5
N1—C6—N2	116.0 (2)
C8—N2—N3—C10	−0.5 (3)	C4—C5—C6—N1	1.3 (4)
C6—N2—N3—C10	−179.4 (2)	C4—C5—C6—N2	−178.7 (2)
C6—N1—C2—C3	0.9 (4)	C8—N2—C6—N1	14.4 (4)
C6—N1—C2—C1	−175.7 (2)	N3—N2—C6—N1	−167.1 (2)
O2—C1—C2—N1	120.9 (4)	C8—N2—C6—C5	−165.6 (3)
O1—C1—C2—N1	−60.7 (4)	N3—N2—C6—C5	12.9 (4)
O2—C1—C2—C3	−55.7 (5)	N3—N2—C8—C9	0.5 (3)
O1—C1—C2—C3	122.8 (3)	C6—N2—C8—C9	179.1 (3)
N1—C2—C3—C4	0.7 (4)	N3—N2—C8—C7	−178.6 (4)
C1—C2—C3—C4	176.9 (3)	C6—N2—C8—C7	0.0 (5)
N1—C2—C3—Cl1	179.7 (2)	N2—C8—C9—C10	−0.3 (4)
C1—C2—C3—Cl1	−4.0 (4)	C7—C8—C9—C10	178.8 (4)
C2—C3—C4—C5	−1.2 (4)	N2—N3—C10—C9	0.4 (4)
Cl1—C3—C4—C5	179.7 (2)	N2—N3—C10—C11	179.5 (3)
C3—C4—C5—C6	0.3 (4)	C8—C9—C10—N3	−0.1 (4)
C2—N1—C6—C5	−1.9 (4)	C8—C9—C10—C11	−179.2 (3)
C2—N1—C6—N2	178.2 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N3^i	0.82	1.92	2.723 (3)	167

Symmetry code: (i) −x, −y+1, z−1/2.