3,4-Di-p-tolyl-6,7-dihydro­imidazo[2,1-b][1,3]thia­zole

The title compound, C₁₉H₁₈N₂S, is a member of a new series of 2,3-dihydro­imidazo[2,1-b][1,3]thia­zoles and was obtained from 4,5-di-p-tolyl-1,3-dihydroimidazole-2-thione and 1-bromo-2-chloro­ethane. The thia­zole ring adopts an envelope conformation; the plane through N, S and two C atoms makes a dihedral angle of 2.35 (3)° with the fused imidazole ring. The tolyl groups are essentially planar.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.063
• wR factor = 0.185
• Data-to-parameter ratio = 15.2

checkCIF/PLATON results

No syntax errors found



Alert level C
REFLT03_ALERT_3_C  Reflection count < 95% complete
           From the CIF: _diffrn_reflns_theta_max           74.16
           From the CIF: _diffrn_reflns_theta_full          74.16
           From the CIF: _reflns_number_total               3018
           TEST2: Reflns within _diffrn_reflns_theta_max
           Count of symmetry unique reflns         3257
           Completeness (_total/calc)             92.66%
PLAT022_ALERT_3_C Ratio Unique / Expected Reflections too Low ....       0.93
PLAT028_ALERT_3_C _diffrn_measured_fraction_theta_max  Low .......       0.93
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT199_ALERT_1_C Check the Reported _cell_measurement_temperature        293 K
PLAT322_ALERT_2_C Check Hybridisation of  S1     in Main Residue .          ?
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          5
PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety        C21
PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety        C20
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          1
              C19 H18 N2 S

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
  10 ALERT level C = Check and explain
   0 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
   4 ALERT type 3 Indicator that the structure quality may be low
   3 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

3,4-Di-p-tolyl-6,7-dihydroimidazo[2,1-b][1,3]thiazole

Crystal data

C19H18N2S	F(000) = 1296
Mr = 306.41	Dx = 1.274 Mg m^−3
Monoclinic, C2/c	Cu Kα radiation, λ = 1.54184 Å
Hall symbol: -C 2yc	Cell parameters from 25 reflections
a = 18.064 (4) Å	θ = 21.2–42.8°
b = 7.901 (2) Å	µ = 1.76 mm^−1
c = 22.401 (7) Å	T = 293 K
β = 91.76 (2)°	Prism, light brown
V = 3195.9 (15) Å^3	0.36 × 0.24 × 0.12 mm
Z = 8

Data collection

Enraf Nonius TurboCAD-4 diffractometer	Rint = 0.034
non–profiled ω scans	θmax = 74.2°, θmin = 4.0°
Absorption correction: ψ scan (North et al., 1968)	h = −22→0
Tmin = 0.632, Tmax = 0.810	k = 0→9
3110 measured reflections	l = −27→27
3018 independent reflections	3 standard reflections every 120 min
2081 reflections with I > 2σ(I)	intensity decay: none

Refinement

Refinement on F^2	0 restraints
Least-squares matrix: full	H-atom parameters constrained
R[F^2 > 2σ(F^2)] = 0.063	w = 1/[σ^2(Fo^2) + (0.0984P)^2 + 2.0386P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.185	(Δ/σ)max < 0.001
S = 1.06	Δρmax = 0.59 e Å^−3
3018 reflections	Δρmin = −0.42 e Å^−3
199 parameters

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.

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

	x	y	z	Uiso*/Ueq
C2	0.1297 (2)	0.9049 (5)	0.02442 (17)	0.0671 (10)
H2A	0.1219	0.7908	0.0095	0.08*
H2B	0.0891	0.9333	0.0499	0.08*
C3	0.13196 (18)	1.0293 (5)	−0.02786 (15)	0.0579 (9)
H1A	0.1048	0.9851	−0.0625	0.069*
H1B	0.1109	1.1376	−0.0171	0.069*
C5	0.25152 (17)	1.1083 (4)	−0.08669 (13)	0.0442 (7)
C6	0.32483 (16)	1.0976 (4)	−0.06574 (13)	0.0440 (7)
C7	0.25890 (18)	1.0033 (4)	0.00440 (13)	0.0480 (7)
C8	0.39419 (16)	1.1459 (4)	−0.09406 (12)	0.0426 (7)
C9	0.46018 (17)	1.0751 (4)	−0.07258 (14)	0.0498 (8)
H14	0.4591	0.998	−0.0413	0.06*
C10	0.52726 (18)	1.1166 (5)	−0.09666 (15)	0.0539 (8)
H15	0.5705	1.0687	−0.0807	0.065*
C11	0.53125 (17)	1.2283 (5)	−0.14404 (15)	0.0524 (8)
C12	0.46545 (18)	1.2979 (5)	−0.16568 (15)	0.0550 (8)
H17	0.4666	1.373	−0.1976	0.066*
C13	0.39789 (18)	1.2591 (4)	−0.14121 (14)	0.0525 (8)
H18	0.3548	1.3093	−0.1565	0.063*
C14	0.21589 (16)	1.1558 (4)	−0.14387 (13)	0.0435 (7)
C15	0.24043 (17)	1.0918 (4)	−0.19792 (13)	0.0484 (8)
H7	0.282	1.0224	−0.198	0.058*
C16	0.20376 (18)	1.1301 (5)	−0.25136 (14)	0.0530 (8)
H8	0.2215	1.0868	−0.2868	0.064*
C17	0.14110 (17)	1.2317 (4)	−0.25328 (14)	0.0501 (8)
C18	0.11741 (18)	1.2976 (5)	−0.19955 (15)	0.0555 (9)
H10	0.0759	1.3673	−0.1997	0.067*
C19	0.15398 (18)	1.2621 (4)	−0.14583 (15)	0.0538 (8)
H11	0.1372	1.3093	−0.1107	0.065*
C20	0.1003 (2)	1.2702 (5)	−0.31163 (16)	0.0676 (10)
H12A	0.0586	1.3418	−0.3042	0.101*
H12B	0.0832	1.1664	−0.3296	0.101*
H12C	0.133	1.3266	−0.3381	0.101*
C21	0.6040 (2)	1.2703 (6)	−0.17189 (18)	0.0708 (11)
H19A	0.5957	1.3494	−0.2039	0.106*
H19B	0.6257	1.1688	−0.1872	0.106*
H19C	0.637	1.3195	−0.1423	0.106*
N4	0.21061 (14)	1.0462 (3)	−0.03994 (11)	0.0464 (6)
N7	0.32813 (14)	1.0307 (4)	−0.00790 (11)	0.0491 (6)
S1	0.21703 (5)	0.91680 (13)	0.06671 (4)	0.0628 (3)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C2	0.065 (2)	0.079 (3)	0.058 (2)	−0.009 (2)	0.0117 (17)	0.007 (2)
C3	0.0467 (19)	0.074 (2)	0.0529 (18)	−0.0054 (17)	0.0063 (14)	−0.0019 (17)
C5	0.0464 (16)	0.0491 (18)	0.0374 (15)	0.0034 (14)	0.0025 (12)	−0.0027 (13)
C6	0.0458 (17)	0.0496 (18)	0.0366 (14)	0.0015 (14)	0.0011 (12)	−0.0013 (13)
C7	0.0551 (19)	0.051 (2)	0.0382 (15)	0.0015 (15)	0.0031 (13)	−0.0016 (14)
C8	0.0429 (15)	0.0490 (17)	0.0358 (14)	−0.0011 (13)	0.0010 (12)	−0.0030 (13)
C9	0.0500 (18)	0.058 (2)	0.0408 (16)	0.0020 (15)	−0.0032 (13)	−0.0027 (14)
C10	0.0420 (17)	0.068 (2)	0.0514 (18)	0.0041 (15)	−0.0032 (14)	−0.0068 (16)
C11	0.0435 (17)	0.060 (2)	0.0539 (18)	−0.0062 (15)	0.0060 (14)	−0.0106 (16)
C12	0.0551 (19)	0.058 (2)	0.0519 (18)	−0.0023 (16)	0.0078 (15)	0.0064 (16)
C13	0.0479 (18)	0.057 (2)	0.0523 (18)	0.0071 (15)	0.0030 (14)	0.0035 (16)
C14	0.0411 (15)	0.0484 (17)	0.0411 (15)	0.0004 (13)	0.0015 (12)	0.0007 (13)
C15	0.0411 (16)	0.058 (2)	0.0462 (17)	0.0076 (14)	0.0041 (13)	0.0000 (15)
C16	0.0515 (18)	0.068 (2)	0.0403 (16)	−0.0012 (16)	0.0057 (13)	0.0000 (15)
C17	0.0447 (17)	0.054 (2)	0.0509 (17)	−0.0080 (15)	−0.0042 (13)	0.0084 (15)
C18	0.0451 (17)	0.060 (2)	0.061 (2)	0.0100 (16)	−0.0041 (15)	0.0051 (17)
C19	0.0499 (18)	0.061 (2)	0.0511 (18)	0.0077 (16)	0.0064 (14)	−0.0050 (16)
C20	0.064 (2)	0.078 (3)	0.060 (2)	−0.0080 (19)	−0.0169 (17)	0.015 (2)
C21	0.054 (2)	0.080 (3)	0.079 (3)	−0.0100 (19)	0.0130 (18)	−0.004 (2)
N4	0.0452 (14)	0.0520 (15)	0.0422 (13)	−0.0001 (12)	0.0058 (10)	−0.0001 (11)
N7	0.0511 (15)	0.0579 (16)	0.0383 (13)	0.0014 (13)	−0.0007 (11)	0.0008 (12)
S1	0.0678 (6)	0.0772 (7)	0.0437 (5)	−0.0071 (5)	0.0087 (4)	0.0076 (4)

Geometric parameters (Å, º)

C2—C3	1.530 (5)	C11—C21	1.509 (5)
C2—S1	1.818 (4)	C12—C13	1.388 (4)
C2—H2A	0.97	C12—H17	0.93
C2—H2B	0.97	C13—H18	0.93
C3—N4	1.461 (4)	C14—C19	1.398 (4)
C3—H1A	0.97	C14—C15	1.397 (4)
C3—H1B	0.97	C15—C16	1.384 (4)
C5—N4	1.390 (4)	C15—H7	0.93
C5—C6	1.394 (4)	C16—C17	1.387 (5)
C5—C14	1.465 (4)	C16—H8	0.93
C6—N7	1.399 (4)	C17—C18	1.391 (5)
C6—C8	1.472 (4)	C17—C20	1.512 (4)
C7—N7	1.307 (4)	C18—C19	1.384 (4)
C7—N4	1.345 (4)	C18—H10	0.93
C7—S1	1.747 (3)	C19—H11	0.93
C8—C13	1.387 (4)	C20—H12A	0.96
C8—C9	1.389 (4)	C20—H12B	0.96
C9—C10	1.381 (5)	C20—H12C	0.96
C9—H14	0.93	C21—H19A	0.96
C10—C11	1.384 (5)	C21—H19B	0.96
C10—H15	0.93	C21—H19C	0.96
C11—C12	1.384 (5)
C3—C2—S1	108.8 (2)	C12—C13—H18	119.8
C3—C2—H2A	109.9	C8—C13—H18	119.8
S1—C2—H2A	109.9	C19—C14—C15	117.7 (3)
C3—C2—H2B	109.9	C19—C14—C5	120.7 (3)
S1—C2—H2B	109.9	C15—C14—C5	121.5 (3)
H2A—C2—H2B	108.3	C16—C15—C14	121.0 (3)
N4—C3—C2	104.5 (3)	C16—C15—H7	119.5
N4—C3—H1A	110.9	C14—C15—H7	119.5
C2—C3—H1A	110.9	C15—C16—C17	121.5 (3)
N4—C3—H1B	110.9	C15—C16—H8	119.3
C2—C3—H1B	110.9	C17—C16—H8	119.3
H1A—C3—H1B	108.9	C18—C17—C16	117.5 (3)
N4—C5—C6	104.3 (3)	C18—C17—C20	121.2 (3)
N4—C5—C14	121.3 (3)	C16—C17—C20	121.3 (3)
C6—C5—C14	134.2 (3)	C17—C18—C19	121.7 (3)
C5—C6—N7	110.3 (3)	C17—C18—H10	119.2
C5—C6—C8	130.7 (3)	C19—C18—H10	119.2
N7—C6—C8	119.0 (3)	C18—C19—C14	120.6 (3)
N7—C7—N4	113.9 (3)	C18—C19—H11	119.7
N7—C7—S1	132.4 (3)	C14—C19—H11	119.7
N4—C7—S1	113.7 (2)	C17—C20—H12A	109.5
C13—C8—C9	117.5 (3)	C17—C20—H12B	109.5
C13—C8—C6	123.8 (3)	H12A—C20—H12B	109.5
C9—C8—C6	118.6 (3)	C17—C20—H12C	109.5
C10—C9—C8	121.5 (3)	H12A—C20—H12C	109.5
C10—C9—H14	119.2	H12B—C20—H12C	109.5
C8—C9—H14	119.2	C11—C21—H19A	109.5
C9—C10—C11	121.2 (3)	C11—C21—H19B	109.5
C9—C10—H15	119.4	H19A—C21—H19B	109.5
C11—C10—H15	119.4	C11—C21—H19C	109.5
C10—C11—C12	117.2 (3)	H19A—C21—H19C	109.5
C10—C11—C21	121.6 (3)	H19B—C21—H19C	109.5
C12—C11—C21	121.2 (3)	C7—N4—C5	107.3 (3)
C13—C12—C11	122.0 (3)	C7—N4—C3	116.9 (3)
C13—C12—H17	119	C5—N4—C3	135.6 (3)
C11—C12—H17	119	C7—N7—C6	104.1 (3)
C12—C13—C8	120.5 (3)	C7—S1—C2	89.66 (16)
S1—C2—C3—N4	26.2 (3)	C14—C15—C16—C17	−0.7 (5)
N4—C5—C6—N7	0.1 (3)	C15—C16—C17—C18	1.6 (5)
C14—C5—C6—N7	−175.0 (3)	C15—C16—C17—C20	−178.7 (3)
N4—C5—C6—C8	−179.1 (3)	C16—C17—C18—C19	−0.9 (5)
C14—C5—C6—C8	5.8 (6)	C20—C17—C18—C19	179.4 (3)
C5—C6—C8—C13	20.4 (5)	C17—C18—C19—C14	−0.9 (5)
N7—C6—C8—C13	−158.8 (3)	C15—C14—C19—C18	1.9 (5)
C5—C6—C8—C9	−159.8 (3)	C5—C14—C19—C18	−175.6 (3)
N7—C6—C8—C9	21.0 (4)	N7—C7—N4—C5	0.1 (4)
C13—C8—C9—C10	0.7 (5)	S1—C7—N4—C5	−178.4 (2)
C6—C8—C9—C10	−179.2 (3)	N7—C7—N4—C3	−176.2 (3)
C8—C9—C10—C11	−1.3 (5)	S1—C7—N4—C3	5.3 (4)
C9—C10—C11—C12	0.8 (5)	C6—C5—N4—C7	−0.1 (3)
C9—C10—C11—C21	−178.1 (3)	C14—C5—N4—C7	175.8 (3)
C10—C11—C12—C13	0.2 (5)	C6—C5—N4—C3	175.1 (3)
C21—C11—C12—C13	179.1 (3)	C14—C5—N4—C3	−9.0 (6)
C11—C12—C13—C8	−0.8 (5)	C2—C3—N4—C7	−20.6 (4)
C9—C8—C13—C12	0.4 (5)	C2—C3—N4—C5	164.4 (3)
C6—C8—C13—C12	−179.8 (3)	N4—C7—N7—C6	−0.1 (4)
N4—C5—C14—C19	49.8 (5)	S1—C7—N7—C6	178.1 (3)
C6—C5—C14—C19	−135.7 (4)	C5—C6—N7—C7	0.0 (3)
N4—C5—C14—C15	−127.6 (3)	C8—C6—N7—C7	179.3 (3)
C6—C5—C14—C15	46.9 (5)	N7—C7—S1—C2	−168.4 (4)
C19—C14—C15—C16	−1.1 (5)	N4—C7—S1—C2	9.9 (3)
C5—C14—C15—C16	176.3 (3)	C3—C2—S1—C7	−21.1 (3)