A new triclinic polymorph of 4,5,6-trimethyl-1-phenyl-3,4-dihydropyrimidine-2(1H)-thione

The title crystal structure, C₁₃H₁₆N₂S, is a triclinic polymorph of the previously reported ortho­rhom­bic structure [Yamin, Kasim & Hamzah (2005). Acta Cryst. E61, o55–o57]. In both structures, the phenyl group is almost perpendicular to the pyrimidine-2-thione ring. In the triclinic structure, inversion-related molecules are linked to form a dimer by N—H...S hydrogen bonds, whereas in the ortho­rhom­bic polymorph two independent mol­ecules are linked by N—H...S hydrogen bonds to form a dimer.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.048
• wR factor = 0.120
• Data-to-parameter ratio = 18.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT154_ALERT_1_C The su's on the Cell Angles are Equal (x 10000)         400 Deg.
PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety        C11

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

   1 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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Computing details

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; 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, PARST (Nardelli, 1995) and PLATON (Spek, 2003).

4,5,6-trimethyl-1-phenyl-3,4-dihydropyrimidine-2(1H)-thione

Crystal data

C13H16N2S	Z = 2
Mr = 232.34	F(000) = 248
Triclinic, P1	Dx = 1.209 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.486 (2) Å	Cell parameters from 4053 reflections
b = 8.649 (2) Å	θ = 2.2–26.5°
c = 10.336 (3) Å	µ = 0.23 mm^−1
α = 108.598 (4)°	T = 298 K
β = 103.053 (4)°	Block, colourless
γ = 107.937 (4)°	0.48 × 0.44 × 0.40 mm
V = 638.4 (3) Å^3

Data collection

Bruker SMART APEX CCD area-detector diffractometer	2620 independent reflections
Radiation source: fine-focus sealed tube	2186 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.024
Detector resolution: 83.66 pixels mm^-1	θmax = 26.5°, θmin = 2.2°
ω scans	h = −10→10
Absorption correction: multi-scan (SADABS; Bruker, 2000)	k = −10→10
Tmin = 0.898, Tmax = 0.914	l = −12→12
6568 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)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.120	H-atom parameters constrained
S = 1.20	w = 1/[σ^2(Fo^2) + (0.0349P)^2 + 0.2733P] where P = (Fo^2 + 2Fc^2)/3
2620 reflections	(Δ/σ)max = 0.001
145 parameters	Δρmax = 0.15 e Å^−3
0 restraints	Δρmin = −0.20 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
S1	0.29366 (8)	0.54872 (7)	0.85797 (7)	0.0515 (2)
N1	0.0232 (2)	0.2275 (2)	0.7380 (2)	0.0451 (4)
N2	0.2934 (2)	0.2490 (2)	0.8659 (2)	0.0480 (5)
H2A	0.4062	0.3115	0.9056	0.058*
C1	−0.1197 (3)	0.3419 (3)	0.5804 (3)	0.0516 (6)
H1A	−0.0605	0.3103	0.5178	0.062*
C2	−0.2358 (4)	0.4194 (4)	0.5489 (3)	0.0624 (7)
H2B	−0.2549	0.4394	0.4646	0.075*
C3	−0.3221 (3)	0.4665 (3)	0.6412 (3)	0.0629 (7)
H3A	−0.3999	0.5182	0.6197	0.075*
C4	−0.2941 (4)	0.4375 (4)	0.7655 (3)	0.0646 (7)
H4A	−0.3527	0.4702	0.8284	0.078*
C5	−0.1793 (3)	0.3600 (3)	0.7981 (3)	0.0550 (6)
H5A	−0.1605	0.3403	0.8826	0.066*
C6	−0.0931 (3)	0.3122 (3)	0.7046 (2)	0.0431 (5)
C7	−0.0494 (3)	0.0390 (3)	0.6953 (3)	0.0484 (5)
C8	0.0472 (3)	−0.0355 (3)	0.7484 (3)	0.0511 (6)
H8A	−0.0026	−0.1593	0.7152	0.061*
C9	0.2316 (3)	0.0666 (3)	0.8585 (3)	0.0455 (5)
C10	0.1983 (3)	0.3295 (3)	0.8196 (2)	0.0399 (5)
C11	−0.2357 (4)	−0.0662 (3)	0.5862 (3)	0.0761 (9)
H11A	−0.2706	−0.1907	0.5656	0.114*
H11B	−0.2412	−0.0508	0.4975	0.114*
H11D	−0.3145	−0.0245	0.6256	0.114*
C12	0.2357 (4)	0.0768 (4)	1.0090 (3)	0.0656 (7)
H12A	0.1557	0.1270	1.0368	0.098*
H12D	0.3540	0.1510	1.0790	0.098*
H12B	0.2001	−0.0413	1.0061	0.098*
C13	0.3578 (3)	−0.0129 (3)	0.8118 (3)	0.0615 (7)
H13D	0.3537	−0.0184	0.7168	0.092*
H13A	0.3227	−0.1313	0.8082	0.092*
H13B	0.4765	0.0610	0.8811	0.092*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0424 (3)	0.0372 (3)	0.0661 (4)	0.0116 (2)	0.0064 (3)	0.0246 (3)
N1	0.0364 (9)	0.0377 (9)	0.0534 (11)	0.0133 (8)	0.0058 (8)	0.0187 (8)
N2	0.0331 (9)	0.0382 (9)	0.0670 (12)	0.0133 (8)	0.0071 (8)	0.0240 (9)
C1	0.0507 (13)	0.0553 (14)	0.0482 (13)	0.0225 (11)	0.0148 (11)	0.0223 (11)
C2	0.0631 (16)	0.0633 (16)	0.0568 (15)	0.0268 (13)	0.0054 (13)	0.0309 (13)
C3	0.0477 (14)	0.0582 (16)	0.0787 (19)	0.0275 (13)	0.0083 (13)	0.0281 (14)
C4	0.0572 (15)	0.0717 (18)	0.0761 (18)	0.0354 (14)	0.0300 (14)	0.0317 (15)
C5	0.0527 (14)	0.0631 (15)	0.0557 (14)	0.0276 (12)	0.0194 (12)	0.0290 (12)
C6	0.0349 (11)	0.0396 (11)	0.0487 (12)	0.0139 (9)	0.0069 (9)	0.0181 (9)
C7	0.0391 (12)	0.0371 (11)	0.0548 (13)	0.0086 (9)	0.0066 (10)	0.0163 (10)
C8	0.0486 (13)	0.0335 (11)	0.0582 (14)	0.0105 (10)	0.0076 (11)	0.0175 (10)
C9	0.0428 (12)	0.0356 (11)	0.0561 (13)	0.0169 (9)	0.0107 (10)	0.0209 (10)
C10	0.0377 (11)	0.0364 (10)	0.0423 (11)	0.0134 (9)	0.0105 (9)	0.0169 (9)
C11	0.0513 (15)	0.0472 (14)	0.093 (2)	0.0040 (12)	−0.0094 (14)	0.0247 (14)
C12	0.0584 (16)	0.0682 (17)	0.0664 (17)	0.0163 (13)	0.0176 (13)	0.0362 (14)
C13	0.0600 (15)	0.0519 (14)	0.0731 (17)	0.0324 (13)	0.0163 (13)	0.0232 (13)

Geometric parameters (Å, º)

S1—C10	1.684 (2)	C5—H5A	0.93
N1—C10	1.360 (3)	C7—C8	1.317 (3)
N1—C7	1.425 (3)	C7—C11	1.501 (3)
N1—C6	1.444 (3)	C8—C9	1.492 (3)
N2—C10	1.322 (3)	C8—H8A	0.93
N2—C9	1.472 (3)	C9—C12	1.522 (3)
N2—H2A	0.86	C9—C13	1.526 (3)
C1—C6	1.371 (3)	C11—H11A	0.96
C1—C2	1.389 (3)	C11—H11B	0.96
C1—H1A	0.93	C11—H11D	0.96
C2—C3	1.365 (4)	C12—H12A	0.96
C2—H2B	0.93	C12—H12D	0.96
C3—C4	1.368 (4)	C12—H12B	0.96
C3—H3A	0.93	C13—H13D	0.96
C4—C5	1.382 (3)	C13—H13A	0.96
C4—H4A	0.93	C13—H13B	0.96
C5—C6	1.375 (3)
C10—N1—C7	120.54 (17)	C9—C8—H8A	118.0
C10—N1—C6	119.75 (17)	N2—C9—C8	107.01 (17)
C7—N1—C6	119.51 (17)	N2—C9—C12	108.89 (19)
C10—N2—C9	128.55 (18)	C8—C9—C12	111.2 (2)
C10—N2—H2A	115.7	N2—C9—C13	107.40 (19)
C9—N2—H2A	115.7	C8—C9—C13	111.7 (2)
C6—C1—C2	119.4 (2)	C12—C9—C13	110.5 (2)
C6—C1—H1A	120.3	N2—C10—N1	117.32 (18)
C2—C1—H1A	120.3	N2—C10—S1	120.68 (16)
C3—C2—C1	120.3 (2)	N1—C10—S1	121.99 (15)
C3—C2—H2B	119.9	C7—C11—H11A	109.5
C1—C2—H2B	119.9	C7—C11—H11B	109.5
C2—C3—C4	120.0 (2)	H11A—C11—H11B	109.5
C2—C3—H3A	120.0	C7—C11—H11D	109.5
C4—C3—H3A	120.0	H11A—C11—H11D	109.5
C3—C4—C5	120.4 (3)	H11B—C11—H11D	109.5
C3—C4—H4A	119.8	C9—C12—H12A	109.5
C5—C4—H4A	119.8	C9—C12—H12D	109.5
C6—C5—C4	119.4 (2)	H12A—C12—H12D	109.5
C6—C5—H5A	120.3	C9—C12—H12B	109.5
C4—C5—H5A	120.3	H12A—C12—H12B	109.5
C1—C6—C5	120.5 (2)	H12D—C12—H12B	109.5
C1—C6—N1	120.6 (2)	C9—C13—H13D	109.5
C5—C6—N1	118.9 (2)	C9—C13—H13A	109.5
C8—C7—N1	120.2 (2)	H13D—C13—H13A	109.5
C8—C7—C11	123.1 (2)	C9—C13—H13B	109.5
N1—C7—C11	116.67 (19)	H13D—C13—H13B	109.5
C7—C8—C9	124.0 (2)	H13A—C13—H13B	109.5
C7—C8—H8A	118.0
C6—C1—C2—C3	0.3 (4)	C6—N1—C7—C11	14.6 (3)
C1—C2—C3—C4	0.1 (4)	N1—C7—C8—C9	2.5 (4)
C2—C3—C4—C5	−0.3 (4)	C11—C7—C8—C9	−179.1 (3)
C3—C4—C5—C6	0.1 (4)	C10—N2—C9—C8	17.3 (3)
C2—C1—C6—C5	−0.5 (3)	C10—N2—C9—C12	−103.1 (3)
C2—C1—C6—N1	178.3 (2)	C10—N2—C9—C13	137.3 (2)
C4—C5—C6—C1	0.3 (4)	C7—C8—C9—N2	−13.2 (3)
C4—C5—C6—N1	−178.5 (2)	C7—C8—C9—C12	105.6 (3)
C10—N1—C6—C1	90.4 (3)	C7—C8—C9—C13	−130.5 (3)
C7—N1—C6—C1	−94.7 (3)	C9—N2—C10—N1	−9.1 (3)
C10—N1—C6—C5	−90.7 (3)	C9—N2—C10—S1	172.22 (18)
C7—N1—C6—C5	84.2 (3)	C7—N1—C10—N2	−4.9 (3)
C10—N1—C7—C8	7.9 (4)	C6—N1—C10—N2	169.9 (2)
C6—N1—C7—C8	−166.9 (2)	C7—N1—C10—S1	173.71 (17)
C10—N1—C7—C11	−170.6 (2)	C6—N1—C10—S1	−11.5 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···S1^i	0.86	2.71	3.465 (2)	148

Symmetry code: (i) −x+1, −y+1, −z+2.