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ISSN: 2056-9890

4-Methyl-N′-(2,2,2-tri­chloro­ethanimido­yl)benzene-1-carboximidamide

aDepartment of Chemistry and Biochemistry, University of Lethbridge, Lethbridge, AB, Canada T1K 3M4
*Correspondence e-mail: boere@uleth.ca

(Received 20 October 2011; accepted 26 October 2011; online 2 November 2011)

The title compound, C10H10Cl3N3, features a delocalized unsaturated N C N C N chain and strong intra­molecular N—H⋯N hydrogen bonding across the chelate ring and also intra­molecular N—H⋯Cl contacts to a CCl3-group Cl atom. The only inter­molecular contacts in the lattice are non-classical hydrogen bonds between methyl and CCl3 groups. The pseudo-six-membered ring is distinctly non-planar by virtue of rotation about the N—C bond between the carboximidamide and imine components [C—N—C—N torsion angle = −23.6 (2) °].

Related literature

For crystal structures of closely related N′-(trichloro/tri­fluoro­ethanimido­yl)aryl-1-carboximidamides, see: Boeré, Roemmele, Suduweli Kondage et al. (2011)[Boeré, R. T., Roemmele, T. L., Suduweli Kondage, S., Zhou, J. & Parvez, M. (2011). Acta Cryst. C67, o273-o277.]; Boeré, Roemmele & Yu (2011[Boeré, R. T., Roemmele, T. L. & Yu, X. (2011). Inorg. Chem. 50, 5123-5136.]). For a review of this less-common class of chelating ligands, see: Kopylovich & Pombeiro (2011[Kopylovich, M. N. & Pombeiro, A. J. L. (2011). Coord. Chem. Rev. 255, 339-355.]).

[Scheme 1]

Experimental

Crystal data
  • C10H10Cl3N3

  • Mr = 278.56

  • Monoclinic, P 21 /c

  • a = 12.2952 (7) Å

  • b = 9.0696 (6) Å

  • c = 11.5407 (7) Å

  • β = 109.661 (1)°

  • V = 1211.90 (13) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.73 mm−1

  • T = 173 K

  • 0.43 × 0.34 × 0.25 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). APEX2, SAINT-Plus and SADABS. Bruker AXS Inc., Madison Wisconsin, USA.]) Tmin = 0.747, Tmax = 0.838

  • 16754 measured reflections

  • 2762 independent reflections

  • 2594 reflections with I > 2σ(I)

  • Rint = 0.014

Refinement
  • R[F2 > 2σ(F2)] = 0.029

  • wR(F2) = 0.077

  • S = 1.08

  • 2762 reflections

  • 158 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.40 e Å−3

  • Δρmin = −0.41 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H2⋯N3 0.83 (2) 2.07 (2) 2.683 (2) 130.8 (18)
N3—H3⋯Cl1 0.81 (2) 2.49 (2) 2.9993 (15) 122.2 (19)
C10—H10A⋯Cl2i 0.98 2.93 3.871 (2) 162 (1)
C10—H10C⋯Cl3ii 0.98 2.93 3.581 (2) 125 (1)
Symmetry codes: (i) -x+1, -y, -z+1; (ii) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2, SAINT-Plus and SADABS. Bruker AXS Inc., Madison Wisconsin, USA.]); cell refinement: SAINT-Plus (Bruker, 2008[Bruker (2008). APEX2, SAINT-Plus and SADABS. Bruker AXS Inc., Madison Wisconsin, USA.]); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

The title compound (Figure 1), commonly known as an imidoylamidine, was prepared as part of our continuing interest in C,N,S based heterocycles (Boeré, Roemmele & Yu, 2011). The molecular structure is very similar to seven independent molecules from our prevous study (Boeré, Roemmele, Suduweli Kondage et al., 2011), with only a single tautomeric form being evidenced in the crystal lattice. The bond lengths and angles for the N CNCN core are nearly identical within the s.u. values to the comparison group. Intramolecular hydrogen bonding occurs between N1—H2···N3 at 2.683 (2) Å to form a pseudo six membered ring. This hydrogen bond is slightly longer (just outside the s.u. values) than the previously reported average of 2.638 (14) Å, which is likely due to a slight rotation of the core (C1—N2—C2—N3 torsion angle = 23.6 (2) °) which causes N3 to be twisted out of the plane of the other four atoms (N1,C1,N2,C2) compared to a range of 4.2 (5) to 16.0 (2) ° for this torsion angle in the comparison group. Also noteworthy is a short intramolecular N3—H3···Cl1 contact at 2.9993 (15) Å, which is within s.u. values of the other known trichloromethyl imidoylamidines. The most surprising feature is the complete lack of intermolecular hydrogen bonding involving the NH or NH2 groups, which was previously observed only in the structure of 4-trifluormethyl-N'-(2,2,2-trichloroethanimidoyl)benzene-1-carboximidamide. In fact, the only short contacts are non-classical hydrogen bonds between the methyl and CCl3 groups, specifically from H10A to Cl2i and H10C to Cl3ii at 2.9272 (5) and 2.9245 (5) Å (Figure 2).

Related literature top

For crystal structures of closely related N'-(trichloro/trifluoroethanimidoyl)aryl-1-carboximidamides, see: Boeré, Roemmele, Suduweli Kondage et al. (2011); Boeré, Roemmele & Yu (2011). For a review of this less-common class of chelating ligands, see: Kopylovich & Pombeiro (2011).

Experimental top

The title compound was prepared as were those described in Boeré, Roemmele, Suduweli Kondage et al. (2011) by addition of trichloroacetonitrile to N,N,N'-4-methylbenzamidine in acetonitrile. Crystals suitable for X-ray diffraction were grown by vacuum sublimation (m.p. 315–317 K).

Refinement top

C-bound H atoms were treated as riding, with C–H = 0.98 Å and Uiso(H) = 1.5Ueq(C) for methyl and C–H = 0.95–0.96 Å and Uiso(H) = 1.2Ueq(C) for all other H atoms. The three N-bound H-atom positions were refined using a distance restraint of 0.88 Å and with Uiso(H) = 1.2Ueq(N).

Structure description top

The title compound (Figure 1), commonly known as an imidoylamidine, was prepared as part of our continuing interest in C,N,S based heterocycles (Boeré, Roemmele & Yu, 2011). The molecular structure is very similar to seven independent molecules from our prevous study (Boeré, Roemmele, Suduweli Kondage et al., 2011), with only a single tautomeric form being evidenced in the crystal lattice. The bond lengths and angles for the N CNCN core are nearly identical within the s.u. values to the comparison group. Intramolecular hydrogen bonding occurs between N1—H2···N3 at 2.683 (2) Å to form a pseudo six membered ring. This hydrogen bond is slightly longer (just outside the s.u. values) than the previously reported average of 2.638 (14) Å, which is likely due to a slight rotation of the core (C1—N2—C2—N3 torsion angle = 23.6 (2) °) which causes N3 to be twisted out of the plane of the other four atoms (N1,C1,N2,C2) compared to a range of 4.2 (5) to 16.0 (2) ° for this torsion angle in the comparison group. Also noteworthy is a short intramolecular N3—H3···Cl1 contact at 2.9993 (15) Å, which is within s.u. values of the other known trichloromethyl imidoylamidines. The most surprising feature is the complete lack of intermolecular hydrogen bonding involving the NH or NH2 groups, which was previously observed only in the structure of 4-trifluormethyl-N'-(2,2,2-trichloroethanimidoyl)benzene-1-carboximidamide. In fact, the only short contacts are non-classical hydrogen bonds between the methyl and CCl3 groups, specifically from H10A to Cl2i and H10C to Cl3ii at 2.9272 (5) and 2.9245 (5) Å (Figure 2).

For crystal structures of closely related N'-(trichloro/trifluoroethanimidoyl)aryl-1-carboximidamides, see: Boeré, Roemmele, Suduweli Kondage et al. (2011); Boeré, Roemmele & Yu (2011). For a review of this less-common class of chelating ligands, see: Kopylovich & Pombeiro (2011).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT-Plus (Bruker, 2008); data reduction: SAINT-Plus (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. Displacement ellipsoid plot (drawn at the 30% probability level) of the title compound. Intramolecular N1···N3 and N3···Cl1 hydrogen bonds (dotted lines) occur in the molecular structure within the crystal lattice.
[Figure 2] Fig. 2. Crystal packing diagram showing the short intermolecular contacts as well as the intramolecular hydrogen bonds.
4-methyl-N'-(2,2,2-trichloroethanimidoyl)benzene-1-carboximidamide top
Crystal data top
C10H10Cl3N3F(000) = 568
Mr = 278.56Dx = 1.527 Mg m3
Monoclinic, P21/cMelting point: 315 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 12.2952 (7) ÅCell parameters from 9876 reflections
b = 9.0696 (6) Åθ = 2.9–27.5°
c = 11.5407 (7) ŵ = 0.73 mm1
β = 109.661 (1)°T = 173 K
V = 1211.90 (13) Å3Prism, colourless
Z = 40.43 × 0.34 × 0.25 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
2762 independent reflections
Radiation source: X-ray, Bruker D82594 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.014
Detector resolution: 0.015 pixels mm-1θmax = 27.5°, θmin = 1.8°
phi and ω scansh = 1515
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
k = 1111
Tmin = 0.747, Tmax = 0.838l = 1414
16754 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.029Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.077H atoms treated by a mixture of independent and constrained refinement
S = 1.08 w = 1/[σ2(Fo2) + (0.0354P)2 + 0.6197P]
where P = (Fo2 + 2Fc2)/3
2762 reflections(Δ/σ)max = 0.001
158 parametersΔρmax = 0.40 e Å3
0 restraintsΔρmin = 0.41 e Å3
Crystal data top
C10H10Cl3N3V = 1211.90 (13) Å3
Mr = 278.56Z = 4
Monoclinic, P21/cMo Kα radiation
a = 12.2952 (7) ŵ = 0.73 mm1
b = 9.0696 (6) ÅT = 173 K
c = 11.5407 (7) Å0.43 × 0.34 × 0.25 mm
β = 109.661 (1)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
2762 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
2594 reflections with I > 2σ(I)
Tmin = 0.747, Tmax = 0.838Rint = 0.014
16754 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0290 restraints
wR(F2) = 0.077H atoms treated by a mixture of independent and constrained refinement
S = 1.08Δρmax = 0.40 e Å3
2762 reflectionsΔρmin = 0.41 e Å3
158 parameters
Special details top

Experimental. A crystal coated in Paratone oil was mounted on the end of a thin glass capillary and cooled in the gas stream of the diffractometer Kryoflex device.

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 (Å2) top
xyzUiso*/Ueq
C10.60366 (11)0.08801 (14)0.75586 (12)0.0251 (3)
C20.78479 (12)0.15175 (16)0.89254 (13)0.0296 (3)
C30.89517 (12)0.22286 (16)0.88006 (12)0.0282 (3)
C40.50862 (11)0.12222 (14)0.63920 (12)0.0247 (3)
C50.39803 (12)0.06308 (16)0.61262 (13)0.0308 (3)
H50.38290.00450.66820.037*
C60.31014 (12)0.10232 (17)0.50565 (14)0.0330 (3)
H60.23540.06090.48880.040*
C70.32937 (12)0.20122 (16)0.42266 (13)0.0299 (3)
C80.44024 (12)0.25899 (17)0.44926 (13)0.0313 (3)
H80.45520.32630.39340.038*
C90.52899 (12)0.22015 (16)0.55551 (13)0.0283 (3)
H90.60400.26030.57150.034*
C100.23320 (14)0.2455 (2)0.30785 (15)0.0413 (4)
H10A0.17640.16560.28280.062*
H10B0.26480.26510.24190.062*
H10C0.19570.33470.32400.062*
N10.59080 (12)0.02814 (15)0.82081 (13)0.0339 (3)
N20.69301 (10)0.17656 (14)0.78685 (11)0.0298 (3)
N30.78334 (13)0.08069 (19)0.98683 (13)0.0434 (3)
Cl11.01604 (3)0.20856 (5)1.01601 (3)0.04137 (12)
Cl20.92765 (3)0.12843 (5)0.76109 (4)0.04211 (12)
Cl30.87281 (4)0.41134 (4)0.84076 (5)0.04654 (12)
H10.5360 (18)0.087 (2)0.7925 (18)0.045 (5)*
H20.6389 (17)0.041 (2)0.8902 (18)0.039 (5)*
H30.846 (2)0.083 (3)1.041 (2)0.055 (6)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0274 (6)0.0241 (6)0.0277 (6)0.0044 (5)0.0141 (5)0.0011 (5)
C20.0292 (7)0.0314 (7)0.0289 (7)0.0001 (5)0.0107 (5)0.0021 (5)
C30.0278 (6)0.0279 (7)0.0279 (6)0.0003 (5)0.0080 (5)0.0000 (5)
C40.0263 (6)0.0229 (6)0.0271 (6)0.0036 (5)0.0118 (5)0.0007 (5)
C50.0304 (7)0.0297 (7)0.0338 (7)0.0013 (5)0.0130 (6)0.0035 (6)
C60.0259 (6)0.0352 (7)0.0378 (8)0.0007 (6)0.0105 (6)0.0002 (6)
C70.0291 (7)0.0315 (7)0.0292 (6)0.0074 (5)0.0100 (5)0.0009 (5)
C80.0332 (7)0.0330 (7)0.0300 (7)0.0036 (6)0.0137 (6)0.0054 (6)
C90.0266 (6)0.0300 (7)0.0309 (7)0.0014 (5)0.0131 (5)0.0015 (5)
C100.0324 (8)0.0489 (9)0.0384 (8)0.0086 (7)0.0066 (6)0.0064 (7)
N10.0350 (7)0.0292 (6)0.0353 (7)0.0021 (5)0.0090 (5)0.0079 (5)
N20.0278 (6)0.0333 (6)0.0281 (6)0.0013 (5)0.0091 (5)0.0061 (5)
N30.0373 (7)0.0599 (9)0.0306 (6)0.0050 (7)0.0080 (6)0.0124 (6)
Cl10.0336 (2)0.0485 (2)0.0339 (2)0.00458 (15)0.00062 (15)0.00111 (15)
Cl20.0371 (2)0.0550 (3)0.0387 (2)0.00594 (17)0.01858 (16)0.01338 (17)
Cl30.0414 (2)0.02872 (19)0.0694 (3)0.00018 (15)0.01851 (19)0.00905 (17)
Geometric parameters (Å, º) top
C1—N21.3098 (18)C6—C71.389 (2)
C1—N11.3328 (18)C6—H60.9500
C1—C41.4885 (18)C7—C81.395 (2)
C2—N31.270 (2)C7—C101.504 (2)
C2—N21.3732 (18)C8—C91.3849 (19)
C2—C31.5525 (19)C8—H80.9500
C3—Cl11.7657 (14)C9—H90.9500
C3—Cl31.7662 (15)C10—H10A0.9800
C3—Cl21.7739 (14)C10—H10B0.9800
C4—C91.3955 (19)C10—H10C0.9800
C4—C51.3964 (19)N1—H10.84 (2)
C5—C61.386 (2)N1—H20.83 (2)
C5—H50.9500N3—H30.81 (2)
N2—C1—N1125.34 (13)C6—C7—C8118.11 (13)
N2—C1—C4116.76 (12)C6—C7—C10120.94 (14)
N1—C1—C4117.90 (13)C8—C7—C10120.94 (14)
N3—C2—N2126.87 (14)C9—C8—C7121.33 (13)
N3—C2—C3123.71 (13)C9—C8—H8119.3
N2—C2—C3109.41 (11)C7—C8—H8119.3
C2—C3—Cl1112.81 (10)C8—C9—C4120.22 (13)
C2—C3—Cl3111.13 (10)C8—C9—H9119.9
Cl1—C3—Cl3108.12 (8)C4—C9—H9119.9
C2—C3—Cl2107.62 (10)C7—C10—H10A109.5
Cl1—C3—Cl2108.12 (8)C7—C10—H10B109.5
Cl3—C3—Cl2108.94 (8)H10A—C10—H10B109.5
C9—C4—C5118.73 (13)C7—C10—H10C109.5
C9—C4—C1119.31 (12)H10A—C10—H10C109.5
C5—C4—C1121.92 (12)H10B—C10—H10C109.5
C6—C5—C4120.46 (13)C1—N1—H1121.3 (14)
C6—C5—H5119.8C1—N1—H2118.1 (14)
C4—C5—H5119.8H1—N1—H2121 (2)
C5—C6—C7121.15 (13)C1—N2—C2120.34 (12)
C5—C6—H6119.4C2—N3—H3111.7 (16)
C7—C6—H6119.4
N3—C2—C3—Cl15.2 (2)C4—C5—C6—C70.2 (2)
N2—C2—C3—Cl1175.64 (10)C5—C6—C7—C80.7 (2)
N3—C2—C3—Cl3126.84 (15)C5—C6—C7—C10178.90 (14)
N2—C2—C3—Cl354.02 (14)C6—C7—C8—C90.4 (2)
N3—C2—C3—Cl2113.95 (16)C10—C7—C8—C9179.23 (14)
N2—C2—C3—Cl265.19 (13)C7—C8—C9—C40.5 (2)
N2—C1—C4—C915.26 (18)C5—C4—C9—C81.0 (2)
N1—C1—C4—C9165.53 (13)C1—C4—C9—C8176.86 (12)
N2—C1—C4—C5162.49 (13)N1—C1—N2—C21.5 (2)
N1—C1—C4—C516.73 (19)C4—C1—N2—C2179.38 (12)
C9—C4—C5—C60.6 (2)N3—C2—N2—C123.6 (2)
C1—C4—C5—C6177.12 (13)C3—C2—N2—C1155.50 (12)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H2···N30.83 (2)2.07 (2)2.683 (2)130.8 (18)
N3—H3···Cl10.81 (2)2.49 (2)2.9993 (15)122.2 (19)
C10—H10A···Cl2i0.982.933.871 (2)162 (1)
C10—H10C···Cl3ii0.982.933.581 (2)125 (1)
Symmetry codes: (i) x+1, y, z+1; (ii) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC10H10Cl3N3
Mr278.56
Crystal system, space groupMonoclinic, P21/c
Temperature (K)173
a, b, c (Å)12.2952 (7), 9.0696 (6), 11.5407 (7)
β (°) 109.661 (1)
V3)1211.90 (13)
Z4
Radiation typeMo Kα
µ (mm1)0.73
Crystal size (mm)0.43 × 0.34 × 0.25
Data collection
DiffractometerBruker APEXII CCD area-detector
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.747, 0.838
No. of measured, independent and
observed [I > 2σ(I)] reflections
16754, 2762, 2594
Rint0.014
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.029, 0.077, 1.08
No. of reflections2762
No. of parameters158
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.40, 0.41

Computer programs: APEX2 (Bruker, 2008), SAINT-Plus (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), Mercury (Macrae et al., 2006), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H2···N30.83 (2)2.07 (2)2.683 (2)130.8 (18)
N3—H3···Cl10.81 (2)2.49 (2)2.9993 (15)122.2 (19)
C10—H10A···Cl2i0.9802.92723.871 (2)162.0 (1)
C10—H10C···Cl3ii0.9802.92453.581 (2)125.3 (1)
Symmetry codes: (i) x+1, y, z+1; (ii) x+1, y+1, z+1.
 

Acknowledgements

This research was supported by the Natural Sciences and Engineering Research Council (NSERC) of Canada. The diffractometer at the University of Lethbridge X-ray Diffraction Facility was purchased with the help of the NSERC and the University of Lethbridge.

References

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First citationMacrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453–457.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
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