4-(2-Pyrid­yl)piperazin-1-ium chloride

The title compound, C₉H₁₄N₃⁺·Cl⁻, crystallizes at room temperature from chloro­form as a zwitterion. The mol­ecules are linked by N—H...Cl hydrogen bonds into chains. The piperazine ring adopts a chair conformation.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.029
• wR factor = 0.061
• Data-to-parameter ratio = 12.2

checkCIF/PLATON results

No syntax errors found



Alert level C
ABSTY03_ALERT_1_C  The _exptl_absorpt_correction_type has been given as none.
            However values have been given for Tmin and Tmax. Remove
            these if an absorption correction has not been applied.
  From the CIF: _exptl_absorpt_correction_T_min   0.873
  From the CIF: _exptl_absorpt_correction_T_max   0.950
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT350_ALERT_3_C Short   C-H Bond (0.96A)   C6     -   H11    ...       0.84 Ang.

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           26.36
           From the CIF: _reflns_number_total               1956
           Count of symmetry unique reflns         1169
           Completeness (_total/calc)            167.32%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       787
           Fraction of Friedel pairs measured     0.673
           Are heavy atom types Z>Si present        yes

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

   2 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
   1 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

Piperazine is freely soluble in water and ethylene glycol, but insoluble in diethyl ether. It is a weak base with a pKb of 4.19; the pH of a 10% aqueous solution is 10.8–11.8. A large number of piperazine compounds have anthelmintic action. Piperazines are also used in the manufacture of plastics, resins, pesticides, brake fluid and other industrial materials (The Merck Index, 1989). The structure of (I) is shown in Fig. 1.

The N—C distances in piperazin-4-ium ring are 1.485 (3) and 1.490 (2) Å, while in the pyridine ring the N—C distance are 1.345 (2) Å. Hydrogen bonds of the type N—H···Cl link the molecules into chains, with N···Cl separation of 3.0961 (17) and 3.1020 (17) Å (Fig. 2).

Related literature

For related literature, see: The Merck Index (1989).

S2. Experimental

1-(2-Pyridinyl)piperazine (1 mmol) and trimethyltin chloride (1 mmol) were suspended in dry chloroform (150 ml) in a round bottom two necked flask. The mixture was stirred at room temperature. Colourless crystals of the title compound obtained accidently after recrystallization in acetone. (Yield 70%°; m.p. 393 K).

S3. Refinement

H atoms were included in difference map positions and refined freely, with C—H distances ranging from 0.84 (2) - 1.00 (2) Å and N—H distances of 0.91 (2) and 0.98 (2) Å.

Computing details

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2001); software used to prepare material for publication: SHELXTL (Bruker, 2001).

Figures

	Fig. 1. Structure of (I) with displacement ellipsoids drawn at the 50% probability level.
	Fig. 2. Packing of (I) viewed down a showing the N—H···Cl hydrogen bonding. H atoms not involved in hydrogen bonding have been omitted for clarity.

4-(2-Pyridyl)piperazin-1-ium chloride

Crystal data

C9H14ClN3	F(000) = 424
Mr = 199.68	Dx = 1.364 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 2404 reflections
a = 7.1757 (6) Å	θ = 3.0–26.3°
b = 7.2196 (6) Å	µ = 0.35 mm^−1
c = 18.7629 (16) Å	T = 100 K
V = 972.02 (14) Å^3	Plate, colourless
Z = 4	0.40 × 0.25 × 0.15 mm

Data collection

Bruker SMART CCD area-detector diffractometer	1781 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.044
Graphite monochromator	θmax = 26.4°, θmin = 2.2°
ϕ and ω scans	h = −8→8
5613 measured reflections	k = −9→8
1956 independent reflections	l = −20→23

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)] = 0.029	Only H-atom coordinates refined
wR(F^2) = 0.061	w = 1/[σ^2(Fo^2) + (0.0272P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.96	(Δ/σ)max < 0.001
1956 reflections	Δρmax = 0.22 e Å^−3
160 parameters	Δρmin = −0.16 e Å^−3
0 restraints	Absolute structure: Flack (1983), 787 Freidel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.04 (7)

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 F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > σ(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ 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	0.24771 (7)	0.33171 (5)	0.23724 (2)	0.02020 (12)
N1	0.3814 (2)	0.6758 (2)	0.32203 (8)	0.0201 (4)
N2	0.3397 (2)	0.90492 (19)	0.44477 (7)	0.0157 (3)
N3	0.4096 (2)	0.9562 (2)	0.56481 (8)	0.0194 (3)
C1	0.4004 (3)	0.5979 (3)	0.39523 (10)	0.0195 (4)
C2	0.4664 (3)	0.7455 (3)	0.44616 (10)	0.0178 (4)
C3	0.3159 (3)	0.9827 (3)	0.37348 (9)	0.0186 (4)
C4	0.2510 (3)	0.8355 (3)	0.32164 (9)	0.0221 (4)
C5	0.3404 (3)	1.0234 (2)	0.50341 (9)	0.0150 (4)
C6	0.2672 (3)	1.2021 (2)	0.49926 (9)	0.0174 (4)
C7	0.2704 (3)	1.3113 (2)	0.55864 (9)	0.0218 (4)
C8	0.3435 (3)	1.2463 (3)	0.62216 (10)	0.0201 (4)
C9	0.4074 (3)	1.0673 (3)	0.62279 (9)	0.0202 (4)
H1	0.494 (3)	0.714 (3)	0.3056 (9)	0.024*
H2	0.336 (3)	0.584 (3)	0.2878 (9)	0.024*
H3	0.485 (3)	0.500 (3)	0.3933 (9)	0.024*
H4	0.274 (3)	0.553 (2)	0.4082 (8)	0.024*
H5	0.595 (3)	0.784 (2)	0.4338 (9)	0.024*
H6	0.474 (3)	0.697 (2)	0.4932 (10)	0.024*
H7	0.219 (3)	1.082 (3)	0.3732 (9)	0.024*
H8	0.431 (3)	1.036 (3)	0.3556 (9)	0.024*
H9	0.244 (3)	0.885 (2)	0.2767 (9)	0.024*
H10	0.129 (3)	0.795 (3)	0.3334 (9)	0.024*
H11	0.217 (3)	1.237 (3)	0.4612 (9)	0.024*
H12	0.223 (3)	1.440 (2)	0.5546 (9)	0.024*
H13	0.350 (3)	1.317 (3)	0.6642 (9)	0.024*
H14	0.453 (3)	1.016 (3)	0.6682 (9)	0.024*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0216 (2)	0.0179 (2)	0.0211 (2)	−0.0011 (2)	0.0015 (2)	−0.00328 (17)
N1	0.0234 (9)	0.0198 (8)	0.0171 (8)	−0.0057 (8)	0.0008 (7)	−0.0045 (7)
N2	0.0198 (8)	0.0144 (7)	0.0129 (7)	0.0023 (7)	−0.0015 (6)	0.0020 (6)
N3	0.0203 (8)	0.0213 (8)	0.0167 (8)	−0.0004 (7)	−0.0005 (6)	−0.0002 (7)
C1	0.0193 (10)	0.0171 (10)	0.0222 (10)	−0.0004 (8)	0.0002 (9)	−0.0002 (8)
C2	0.0198 (11)	0.0171 (9)	0.0165 (9)	0.0031 (8)	−0.0025 (8)	0.0015 (8)
C3	0.0229 (10)	0.0181 (9)	0.0149 (9)	0.0010 (8)	−0.0030 (8)	0.0015 (8)
C4	0.0253 (10)	0.0245 (9)	0.0164 (8)	−0.0004 (13)	−0.0044 (10)	0.0020 (8)
C5	0.0125 (9)	0.0167 (9)	0.0158 (9)	−0.0015 (8)	0.0024 (7)	0.0025 (8)
C6	0.0179 (10)	0.0170 (9)	0.0172 (8)	0.0007 (9)	−0.0012 (9)	0.0042 (7)
C7	0.0198 (11)	0.0159 (9)	0.0297 (10)	0.0004 (9)	0.0028 (9)	0.0016 (8)
C8	0.0189 (10)	0.0222 (10)	0.0191 (10)	−0.0035 (9)	0.0039 (8)	−0.0062 (8)
C9	0.0185 (10)	0.0277 (11)	0.0143 (9)	−0.0012 (8)	−0.0003 (8)	0.0027 (8)

Geometric parameters (Å, º)

N1—C4	1.485 (3)	C3—C4	1.514 (2)
N1—C1	1.490 (2)	C3—H7	0.998 (19)
N1—H1	0.91 (2)	C3—H8	0.97 (2)
N1—H2	0.979 (19)	C4—H9	0.918 (17)
N2—C5	1.394 (2)	C4—H10	0.95 (2)
N2—C3	1.461 (2)	C5—C6	1.395 (2)
N2—C2	1.467 (2)	C6—C7	1.365 (2)
N3—C5	1.345 (2)	C6—H11	0.840 (19)
N3—C9	1.352 (2)	C7—C8	1.384 (3)
C1—C2	1.508 (3)	C7—H12	0.991 (19)
C1—H3	0.93 (2)	C8—C9	1.371 (3)
C1—H4	1.00 (2)	C8—H13	0.939 (18)
C2—H5	0.99 (2)	C9—H14	0.985 (17)
C2—H6	0.951 (18)
C4—N1—C1	110.81 (14)	N2—C3—H8	111.7 (11)
C4—N1—H1	108.9 (12)	C4—C3—H8	108.5 (11)
C1—N1—H1	110.2 (11)	H7—C3—H8	107.6 (15)
C4—N1—H2	108.4 (11)	N1—C4—C3	110.37 (16)
C1—N1—H2	112.2 (11)	N1—C4—H9	110.1 (12)
H1—N1—H2	106.2 (15)	C3—C4—H9	109.3 (11)
C5—N2—C3	119.17 (14)	N1—C4—H10	109.8 (12)
C5—N2—C2	117.74 (14)	C3—C4—H10	110.6 (11)
C3—N2—C2	112.98 (14)	H9—C4—H10	106.5 (17)
C5—N3—C9	118.09 (15)	N3—C5—N2	117.13 (15)
N1—C1—C2	110.24 (15)	N3—C5—C6	121.36 (15)
N1—C1—H3	108.1 (11)	N2—C5—C6	121.48 (15)
C2—C1—H3	110.9 (12)	C7—C6—C5	118.83 (16)
N1—C1—H4	105.4 (10)	C7—C6—H11	121.8 (13)
C2—C1—H4	111.3 (9)	C5—C6—H11	119.2 (13)
H3—C1—H4	110.7 (16)	C6—C7—C8	120.90 (17)
N2—C2—C1	110.42 (15)	C6—C7—H12	118.2 (10)
N2—C2—H5	110.6 (11)	C8—C7—H12	120.9 (10)
C1—C2—H5	110.0 (11)	C9—C8—C7	116.97 (17)
N2—C2—H6	110.0 (11)	C9—C8—H13	119.1 (12)
C1—C2—H6	110.3 (10)	C7—C8—H13	123.9 (12)
H5—C2—H6	105.4 (16)	N3—C9—C8	123.80 (17)
N2—C3—C4	110.76 (15)	N3—C9—H14	118.1 (11)
N2—C3—H7	111.3 (10)	C8—C9—H14	118.1 (11)
C4—C3—H7	106.7 (10)
C4—N1—C1—C2	−57.5 (2)	C3—N2—C5—N3	−163.18 (16)
C5—N2—C2—C1	158.72 (16)	C2—N2—C5—N3	−20.2 (2)
C3—N2—C2—C1	−56.1 (2)	C3—N2—C5—C6	18.7 (3)
N1—C1—C2—N2	56.1 (2)	C2—N2—C5—C6	161.74 (17)
C5—N2—C3—C4	−159.81 (17)	N3—C5—C6—C7	1.5 (3)
C2—N2—C3—C4	55.5 (2)	N2—C5—C6—C7	179.50 (18)
C1—N1—C4—C3	56.9 (2)	C5—C6—C7—C8	−0.5 (3)
N2—C3—C4—N1	−55.2 (2)	C6—C7—C8—C9	−1.5 (3)
C9—N3—C5—N2	−178.43 (16)	C5—N3—C9—C8	−1.9 (3)
C9—N3—C5—C6	−0.3 (3)	C7—C8—C9—N3	2.8 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H2···Cl1	0.979 (19)	2.15 (2)	3.1020 (17)	164.3 (15)
N1—H1···Cl1^i	0.91 (2)	2.19 (2)	3.0961 (17)	174.3 (17)

Symmetry code: (i) −x+1, y+1/2, −z+1/2.