N-(4-Chloro­phen­yl)-4-methyl­pyridin-2-amine

In the title compound, C₁₂H₁₁ClN₂, the dihedral angle between the benzene and pyridyl rings is 48.03 (8)°. Twists are also evident in the mol­ecule, in particular about the N_a–C_b (a = amine and b = benzene) bond [C—N—C—C = −144.79 (18)°]. In the crystal, inversion dimers linked by pairs of N—H...N hydrogen bonds result in the formation of eight-membered {...NCNH}₂ synthons [or R₂²(8) loops].

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.042
• wR factor = 0.132
• Data-to-parameter ratio = 17.8

checkCIF/PLATON results

No syntax errors found



Alert level C
SHFSU01_ALERT_2_C  Test not performed. _refine_ls_shift/su_max and
            _refine_ls_shift/esd_max not present.
            Absolute value of the parameter shift to su ratio given   0.001
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          1

Alert level G
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1
PLAT128_ALERT_4_G Alternate Setting of Space-group P21/c   .......      P21/n
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported   _diffrn_ambient_temperature        293 K

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

   2 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
   2 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 title compound, (I), was investigated in the context of potential fluorescence properties (Kawai et al. 2001; Abdullah, 2005). The molecular structure of (I), Fig. 1, shows that the molecule is non-planar as seen in the dihedral angle of 48.03 (8) ° formed between the benzene and pyridyl rings, and in the twists about the central N–C bonds, i.e. the C7–N2–C1–N1 and C1–N2–C7–C8 torsion angles are -167.92 (17) and -144.79 (18) °, respectively. The amine-H and pyridine-N atoms are orientated in the same direction, an arrangement that facilitates the formation of N–H···N hydrogen bonds. Thus, centrosymmetrically related molecules are linked via N–H···N hydrogen bonds that lead to eight-membered {···NCNH}₂ synthons, Table 1. The dimeric aggregates stack along the b axis, Fig. 2.

Related literature

For background to the fluorescence properties of compounds related to the title compound, see: Kawai et al. (2001); Abdullah (2005).

S2. Experimental

2-Chloro-4-methylpyridine (1.0 ml, 1.14 mmol) was added to 4-chloroaniline (1.4543 g, 1.14 mmol) and heated for 2 h. The mixture was cooled and dissolved water (15 ml), extracted with diethyl ether (3 × 10 ml), washed with water (3 × 10 ml), and then dried over anhydrous sodium sulfate. Evaporation of the solvent gave a gray solid. Recrystallization from ethanol yielded colourless blocks of (I).

S3. Refinement

Carbon-bound H-atoms were placed in calculated positions (C—H 0.93 to 0.96 Å) and were included in the refinement in the riding model approximation, with U_iso(H) set to 1.2 to 1.5U_equiv(C). The N-bound H-atom was located in a difference Fourier map, and was refined with a distance restraint of N–H 0.86±0.01 Å; the U_iso value was freely refined.

Computing details

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures

	Fig. 1. The molecular structure of (I) showing displacement ellipsoids at the 35% probability level.
	Fig. 2. Unit-cell contents shown in projection down the b axis in (I). The N–H···N hydrogen bonding is shown as orange dashed lines.

N-(4-Chlorophenyl)-4-methylpyridin-2-amine

Crystal data

C12H11ClN2	F(000) = 456
Mr = 218.68	Dx = 1.333 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2763 reflections
a = 15.9335 (15) Å	θ = 2.4–25.7°
b = 4.0651 (4) Å	µ = 0.32 mm^−1
c = 17.0153 (16) Å	T = 293 K
β = 98.755 (1)°	Block, colourless
V = 1089.26 (18) Å^3	0.30 × 0.30 × 0.20 mm
Z = 4

Data collection

Bruker SMART APEX CCD diffractometer	2509 independent reflections
Radiation source: fine-focus sealed tube	1886 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.030
ω scans	θmax = 27.5°, θmin = 1.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −20→19
Tmin = 0.776, Tmax = 0.862	k = −5→5
9785 measured reflections	l = −22→20

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)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.132	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0689P)^2 + 0.1992P] where P = (Fo^2 + 2Fc^2)/3
2509 reflections	(Δ/σ)max < 0.001
141 parameters	Δρmax = 0.22 e Å^−3
1 restraint	Δρmin = −0.18 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
Cl1	0.59502 (4)	1.02913 (16)	0.10424 (3)	0.0834 (2)
N1	0.60831 (9)	0.5290 (4)	0.56614 (8)	0.0495 (4)
N2	0.57324 (9)	0.6997 (4)	0.43820 (9)	0.0552 (4)
H2n	0.5222 (7)	0.653 (5)	0.4444 (11)	0.061 (6)*
C1	0.63451 (10)	0.6751 (4)	0.50365 (9)	0.0439 (4)
C2	0.66466 (12)	0.5088 (5)	0.63260 (11)	0.0578 (5)
H2	0.6472	0.4101	0.6767	0.069*
C3	0.74612 (12)	0.6230 (5)	0.64035 (10)	0.0570 (5)
H3	0.7827	0.5985	0.6881	0.068*
C4	0.77369 (11)	0.7769 (4)	0.57556 (10)	0.0498 (4)
C5	0.71648 (10)	0.8019 (4)	0.50667 (10)	0.0461 (4)
H5	0.7323	0.9030	0.4621	0.055*
C6	0.86175 (12)	0.9137 (6)	0.58031 (13)	0.0661 (5)
H6A	0.8620	1.0847	0.5414	0.099*
H6B	0.8999	0.7416	0.5701	0.099*
H6C	0.8797	1.0023	0.6325	0.099*
C7	0.58319 (10)	0.7850 (4)	0.36041 (9)	0.0428 (4)
C8	0.51945 (11)	0.9664 (4)	0.31600 (11)	0.0496 (4)
H8	0.4740	1.0406	0.3396	0.059*
C9	0.52239 (12)	1.0389 (4)	0.23723 (11)	0.0544 (4)
H9	0.4789	1.1588	0.2077	0.065*
C10	0.59014 (12)	0.9323 (4)	0.20290 (10)	0.0493 (4)
C11	0.65418 (11)	0.7545 (4)	0.24569 (10)	0.0481 (4)
H11	0.6998	0.6843	0.2219	0.058*
C12	0.65108 (10)	0.6791 (4)	0.32428 (10)	0.0462 (4)
H12	0.6946	0.5570	0.3532	0.055*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.1035 (5)	0.0997 (5)	0.0472 (3)	−0.0123 (3)	0.0123 (3)	0.0172 (3)
N1	0.0440 (8)	0.0626 (9)	0.0425 (8)	0.0058 (6)	0.0082 (6)	0.0026 (6)
N2	0.0364 (8)	0.0858 (12)	0.0428 (8)	−0.0052 (7)	0.0048 (6)	0.0083 (7)
C1	0.0414 (8)	0.0494 (9)	0.0409 (8)	0.0059 (7)	0.0061 (6)	−0.0034 (7)
C2	0.0582 (11)	0.0722 (13)	0.0430 (9)	0.0070 (9)	0.0072 (8)	0.0058 (8)
C3	0.0574 (11)	0.0673 (11)	0.0424 (9)	0.0083 (9)	−0.0051 (8)	−0.0042 (8)
C4	0.0481 (9)	0.0476 (9)	0.0515 (10)	0.0039 (7)	0.0006 (7)	−0.0127 (7)
C5	0.0452 (9)	0.0486 (9)	0.0439 (9)	−0.0008 (7)	0.0049 (7)	−0.0019 (7)
C6	0.0535 (11)	0.0693 (12)	0.0705 (13)	−0.0074 (9)	−0.0066 (9)	−0.0119 (10)
C7	0.0379 (8)	0.0485 (9)	0.0409 (8)	−0.0039 (7)	0.0027 (6)	−0.0004 (7)
C8	0.0436 (9)	0.0535 (10)	0.0512 (10)	0.0057 (7)	0.0059 (7)	−0.0012 (7)
C9	0.0539 (10)	0.0521 (10)	0.0541 (10)	0.0051 (8)	−0.0019 (8)	0.0089 (8)
C10	0.0572 (10)	0.0488 (9)	0.0411 (8)	−0.0110 (8)	0.0052 (7)	0.0025 (7)
C11	0.0440 (9)	0.0518 (10)	0.0495 (9)	−0.0053 (7)	0.0101 (7)	−0.0027 (7)
C12	0.0373 (8)	0.0517 (9)	0.0486 (9)	0.0024 (7)	0.0032 (7)	0.0034 (7)

Geometric parameters (Å, º)

Cl1—C10	1.7376 (18)	C6—H6A	0.9600
N1—C2	1.335 (2)	C6—H6B	0.9600
N1—C1	1.339 (2)	C6—H6C	0.9600
N2—C1	1.368 (2)	C7—C8	1.383 (2)
N2—C7	1.400 (2)	C7—C12	1.391 (2)
N2—H2n	0.857 (9)	C8—C9	1.380 (2)
C1—C5	1.398 (2)	C8—H8	0.9300
C2—C3	1.366 (3)	C9—C10	1.373 (3)
C2—H2	0.9300	C9—H9	0.9300
C3—C4	1.396 (3)	C10—C11	1.367 (2)
C3—H3	0.9300	C11—C12	1.380 (2)
C4—C5	1.375 (2)	C11—H11	0.9300
C4—C6	1.500 (3)	C12—H12	0.9300
C5—H5	0.9300
C2—N1—C1	116.69 (15)	C4—C6—H6C	109.5
C1—N2—C7	128.17 (14)	H6A—C6—H6C	109.5
C1—N2—H2n	117.2 (13)	H6B—C6—H6C	109.5
C7—N2—H2n	114.6 (13)	C8—C7—C12	118.64 (15)
N1—C1—N2	114.12 (15)	C8—C7—N2	117.97 (15)
N1—C1—C5	122.47 (15)	C12—C7—N2	123.27 (15)
N2—C1—C5	123.36 (15)	C9—C8—C7	120.91 (16)
N1—C2—C3	124.59 (18)	C9—C8—H8	119.5
N1—C2—H2	117.7	C7—C8—H8	119.5
C3—C2—H2	117.7	C10—C9—C8	119.40 (16)
C2—C3—C4	119.00 (16)	C10—C9—H9	120.3
C2—C3—H3	120.5	C8—C9—H9	120.3
C4—C3—H3	120.5	C11—C10—C9	120.77 (16)
C5—C4—C3	117.32 (16)	C11—C10—Cl1	119.67 (14)
C5—C4—C6	120.81 (17)	C9—C10—Cl1	119.55 (14)
C3—C4—C6	121.87 (16)	C10—C11—C12	119.99 (16)
C4—C5—C1	119.92 (16)	C10—C11—H11	120.0
C4—C5—H5	120.0	C12—C11—H11	120.0
C1—C5—H5	120.0	C11—C12—C7	120.28 (15)
C4—C6—H6A	109.5	C11—C12—H12	119.9
C4—C6—H6B	109.5	C7—C12—H12	119.9
H6A—C6—H6B	109.5
C2—N1—C1—N2	−177.70 (15)	C1—N2—C7—C8	−144.79 (18)
C2—N1—C1—C5	0.0 (2)	C1—N2—C7—C12	39.4 (3)
C7—N2—C1—N1	−167.92 (17)	C12—C7—C8—C9	0.6 (3)
C7—N2—C1—C5	14.4 (3)	N2—C7—C8—C9	−175.42 (16)
C1—N1—C2—C3	−0.7 (3)	C7—C8—C9—C10	−0.8 (3)
N1—C2—C3—C4	1.0 (3)	C8—C9—C10—C11	0.3 (3)
C2—C3—C4—C5	−0.6 (3)	C8—C9—C10—Cl1	−178.88 (14)
C2—C3—C4—C6	178.85 (18)	C9—C10—C11—C12	0.2 (3)
C3—C4—C5—C1	−0.1 (2)	Cl1—C10—C11—C12	179.44 (13)
C6—C4—C5—C1	−179.50 (17)	C10—C11—C12—C7	−0.4 (3)
N1—C1—C5—C4	0.4 (3)	C8—C7—C12—C11	−0.1 (2)
N2—C1—C5—C4	177.85 (16)	N2—C7—C12—C11	175.77 (15)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2n···N1^i	0.86 (1)	2.19 (1)	3.029 (2)	167 (2)

Symmetry code: (i) −x+1, −y+1, −z+1.