4-(2,4,6-Trimethyl­benz­yl)-1,3-thia­zol-2-amine

The methyl­ene C atom in the title compound, C₁₃H₁₆N₂S, is connected to a five-membered thia­zole ring and a mesityl substituent. The rings are aligned at 75.4 (1)°. The amino substitutent inter­acts with the ring N atom of an adjacent mol­ecule by an inter­molecular N—H...N hydrogen bond, generating a helical chain running along the b axis.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.045
• wR factor = 0.120
• Data-to-parameter ratio = 17.6

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT029_ALERT_3_B _diffrn_measured_fraction_theta_full Low .......       0.96

Alert level C
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          1
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600         50
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600         67

Alert level G
PLAT002_ALERT_2_G Number of Distance or Angle Restraints on AtSite          3
PLAT128_ALERT_4_G Alternate Setting of Space-group P21/c   .......      P21/n
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          2

   0 ALERT level A = Most likely a serious problem - resolve or explain
   1 ALERT level B = A potentially serious problem, consider carefully
   3 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   3 ALERT level G = General information/check it is not something unexpected

   0 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
   4 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

A recent study reported the reaction of 1-chloro-3-(2,4,6-trimethylphenyl)-propan-2-one with primary amines. The chlorine atom in the α-chloro ketone is not replaced directly by an amino RNH– group. The intermediate product undergoes a Favorskii rearrangement that furnishes a compound having two methylene groups between the aromatic system and the amido unit (Yadigarov et al., 2010). The present study employs thiourea as the amine. One of its amino –NH₂ groups is involved in the formation of the thiazolyl ring in the resulting product (Scheme I, Fig. 1). The methylene carbon is connected to the five-membered thiazolyl ring and the six-membered mesityl group. The rings are aligned at 75.4 (1) °. The amino –NH₂ substitutent interacts with the ring N atom of an adjacent molecule by an N–H···N hydrogen bond generating a helical chain that runs along the b-axis of the monoclinic unit cell.

Related literature

For background to the synthetic procedure,: see: Yadigarov et al. (2010).

S2. Experimental

1-Chloro-3-(2,4,6-trimethylphenyl)-propan-2-one (10 mmol) and thiourea (10 mmol) were stirred in water (100 ml) for an hour. A precipitate formed and this was collected and redissolved in hot ethanol. Slow evaporation of the solvent gave colorless crystals in 50% yield; m.p. 380–381 K.

S3. Refinement

Carbon-bound H-atoms were placed in calculated positions [C–H 0.93 to 0.97 Å] and were included in the refinement in the riding model approximation, with U_iso(H) set to 1.2-1.5 U_eq(C).

The amino H-atoms were located in a difference Fourier map and were refined with a distance restraint of N–H 0.88±0.01 Å; their temperature factors were refined isotropically.

Computing details

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures

Fig. 1. Thermal ellipsoid plot (Barbour, 2001) of C13H16N2S at the 70% probability level; hydrogen atoms are drawn as spheres of arbitrary radius.

4-(2,4,6-Trimethylbenzyl)-1,3-thiazol-2-amine

Crystal data

C13H16N2S	F(000) = 496
Mr = 232.34	Dx = 1.235 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 3598 reflections
a = 5.5028 (5) Å	θ = 2.6–29.1°
b = 30.832 (3) Å	µ = 0.23 mm^−1
c = 7.8355 (7) Å	T = 100 K
β = 110.016 (1)°	Prism, colorless
V = 1249.08 (19) Å^3	0.30 × 0.20 × 0.20 mm
Z = 4

Data collection

Bruker APEXII diffractometer	2749 independent reflections
Radiation source: fine-focus sealed tube	2486 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.024
ϕ and ω scans	θmax = 27.5°, θmin = 2.6°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −7→7
Tmin = 0.933, Tmax = 0.955	k = −40→24
7129 measured reflections	l = −9→10

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)] = 0.045	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.120	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	w = 1/[σ^2(Fo^2) + (0.060P)^2 + 0.6878P] where P = (Fo^2 + 2Fc^2)/3
2749 reflections	(Δ/σ)max = 0.001
156 parameters	Δρmax = 0.38 e Å^−3
2 restraints	Δρmin = −0.24 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
S1	0.65720 (8)	0.220399 (14)	0.75764 (6)	0.02680 (15)
N1	0.2450 (3)	0.26387 (5)	0.7802 (2)	0.0283 (3)
H11	0.351 (3)	0.2757 (6)	0.8795 (19)	0.030 (5)*
H12	0.080 (2)	0.2637 (8)	0.764 (3)	0.038 (6)*
N2	0.1780 (3)	0.20379 (5)	0.58369 (19)	0.0241 (3)
C1	0.3278 (3)	0.23024 (5)	0.7040 (2)	0.0215 (3)
C2	0.5821 (3)	0.17807 (6)	0.6029 (2)	0.0267 (4)
H2	0.7056	0.1604	0.5759	0.032*
C3	0.3239 (3)	0.17382 (5)	0.5263 (2)	0.0244 (3)
C4	0.1797 (4)	0.13975 (6)	0.3931 (3)	0.0338 (4)
H4A	0.0544	0.1542	0.2862	0.041*
H4B	0.0800	0.1217	0.4502	0.041*
C5	0.3520 (3)	0.11046 (6)	0.3288 (2)	0.0282 (4)
C6	0.3814 (4)	0.11748 (6)	0.1605 (2)	0.0301 (4)
C7	0.5436 (4)	0.09018 (7)	0.1069 (3)	0.0344 (4)
H7	0.5633	0.0950	−0.0075	0.041*
C8	0.6772 (4)	0.05629 (6)	0.2137 (3)	0.0344 (4)
C9	0.6454 (4)	0.04995 (6)	0.3799 (3)	0.0365 (4)
H9	0.7352	0.0269	0.4557	0.044*
C10	0.4858 (4)	0.07644 (6)	0.4388 (3)	0.0336 (4)
C11	0.2363 (5)	0.15279 (7)	0.0330 (3)	0.0473 (6)
H11A	0.2694	0.1807	0.0966	0.071*
H11B	0.0505	0.1465	−0.0085	0.071*
H11C	0.2946	0.1541	−0.0719	0.071*
C12	0.8478 (4)	0.02682 (8)	0.1499 (3)	0.0487 (6)
H12A	0.9348	0.0438	0.0820	0.073*
H12B	0.7419	0.0042	0.0711	0.073*
H12C	0.9776	0.0133	0.2552	0.073*
C13	0.4571 (7)	0.06770 (8)	0.6208 (3)	0.0609 (8)
H13A	0.5687	0.0434	0.6802	0.091*
H13B	0.2767	0.0605	0.6029	0.091*
H13C	0.5074	0.0936	0.6974	0.091*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0157 (2)	0.0299 (2)	0.0334 (3)	−0.00014 (16)	0.00646 (16)	−0.00426 (18)
N1	0.0173 (7)	0.0329 (8)	0.0320 (8)	0.0012 (6)	0.0049 (6)	−0.0077 (7)
N2	0.0193 (7)	0.0246 (7)	0.0269 (7)	−0.0006 (6)	0.0061 (5)	−0.0005 (6)
C1	0.0171 (7)	0.0248 (8)	0.0214 (7)	0.0014 (6)	0.0051 (6)	0.0038 (6)
C2	0.0229 (8)	0.0246 (8)	0.0342 (9)	0.0014 (7)	0.0118 (7)	−0.0012 (7)
C3	0.0241 (8)	0.0230 (8)	0.0267 (8)	0.0000 (7)	0.0096 (6)	0.0010 (7)
C4	0.0296 (9)	0.0303 (9)	0.0407 (10)	−0.0038 (8)	0.0110 (8)	−0.0094 (8)
C5	0.0298 (9)	0.0229 (8)	0.0295 (9)	−0.0032 (7)	0.0072 (7)	−0.0051 (7)
C6	0.0343 (9)	0.0249 (9)	0.0255 (9)	−0.0034 (7)	0.0031 (7)	−0.0002 (7)
C7	0.0414 (10)	0.0374 (11)	0.0234 (9)	−0.0047 (9)	0.0098 (8)	−0.0049 (8)
C8	0.0328 (10)	0.0319 (10)	0.0339 (10)	−0.0014 (8)	0.0055 (8)	−0.0129 (8)
C9	0.0458 (11)	0.0245 (9)	0.0292 (9)	0.0056 (8)	0.0000 (8)	−0.0014 (8)
C10	0.0489 (11)	0.0239 (9)	0.0260 (9)	−0.0024 (8)	0.0102 (8)	−0.0025 (7)
C11	0.0621 (14)	0.0328 (11)	0.0353 (11)	0.0052 (10)	0.0016 (10)	0.0071 (9)
C12	0.0402 (12)	0.0481 (13)	0.0552 (14)	0.0031 (10)	0.0127 (10)	−0.0213 (11)
C13	0.118 (2)	0.0327 (12)	0.0400 (13)	0.0024 (13)	0.0379 (15)	0.0050 (10)

Geometric parameters (Å, º)

S1—C2	1.7323 (18)	C7—C8	1.383 (3)
S1—C1	1.7415 (16)	C7—H7	0.9500
N1—C1	1.351 (2)	C8—C9	1.386 (3)
N1—H11	0.88 (1)	C8—C12	1.509 (3)
N1—H12	0.87 (1)	C9—C10	1.389 (3)
N2—C1	1.304 (2)	C9—H9	0.9500
N2—C3	1.396 (2)	C10—C13	1.512 (3)
C2—C3	1.346 (2)	C11—H11A	0.9800
C2—H2	0.9500	C11—H11B	0.9800
C3—C4	1.502 (2)	C11—H11C	0.9800
C4—C5	1.515 (2)	C12—H12A	0.9800
C4—H4A	0.9900	C12—H12B	0.9800
C4—H4B	0.9900	C12—H12C	0.9800
C5—C10	1.397 (3)	C13—H13A	0.9800
C5—C6	1.399 (3)	C13—H13B	0.9800
C6—C7	1.393 (3)	C13—H13C	0.9800
C6—C11	1.508 (3)
C2—S1—C1	89.03 (8)	C6—C7—H7	118.8
C1—N1—H11	119.3 (14)	C7—C8—C9	117.63 (18)
C1—N1—H12	115.1 (16)	C7—C8—C12	121.1 (2)
H11—N1—H12	118 (2)	C9—C8—C12	121.3 (2)
C1—N2—C3	110.84 (14)	C8—C9—C10	121.79 (18)
N2—C1—N1	125.03 (15)	C8—C9—H9	119.1
N2—C1—S1	114.43 (12)	C10—C9—H9	119.1
N1—C1—S1	120.50 (13)	C9—C10—C5	119.78 (17)
C3—C2—S1	110.36 (13)	C9—C10—C13	119.37 (19)
C3—C2—H2	124.8	C5—C10—C13	120.84 (19)
S1—C2—H2	124.8	C6—C11—H11A	109.5
C2—C3—N2	115.33 (15)	C6—C11—H11B	109.5
C2—C3—C4	127.16 (16)	H11A—C11—H11B	109.5
N2—C3—C4	117.47 (15)	C6—C11—H11C	109.5
C3—C4—C5	113.94 (15)	H11A—C11—H11C	109.5
C3—C4—H4A	108.8	H11B—C11—H11C	109.5
C5—C4—H4A	108.8	C8—C12—H12A	109.5
C3—C4—H4B	108.8	C8—C12—H12B	109.5
C5—C4—H4B	108.8	H12A—C12—H12B	109.5
H4A—C4—H4B	107.7	C8—C12—H12C	109.5
C10—C5—C6	119.39 (17)	H12A—C12—H12C	109.5
C10—C5—C4	120.04 (17)	H12B—C12—H12C	109.5
C6—C5—C4	120.56 (17)	C10—C13—H13A	109.5
C5—C6—C7	118.95 (17)	C10—C13—H13B	109.5
C5—C6—C11	122.00 (18)	H13A—C13—H13B	109.5
C7—C6—C11	119.01 (18)	C10—C13—H13C	109.5
C8—C7—C6	122.45 (18)	H13A—C13—H13C	109.5
C8—C7—H7	118.8	H13B—C13—H13C	109.5

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H11···N2^i	0.88 (1)	2.06 (1)	2.907 (2)	163 (2)

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