Synthesis, crystal structure and Hirshfeld surface analysis of the ortho­rhom­bic polymorph of 4-bromo-N-(4-bromo­benzyl­idene)aniline

The crystal structure of the ortho­rhom­bic polymorph of N-(4-bromo­benzyl­idene)-4-bromo­aniline, C₁₃H₉Br₂N, is reported for the first time. The mol­ecule is disordered about a crystallographic inversion center.

Key indicators

Structure: I

• Single-crystal X-ray study
• T = 173 K
• Mean [sigma](C-C) = 0.005 Å
• Disorder in main residue
• R factor = 0.037
• wR factor = 0.061
• Data-to-parameter ratio = 15.8

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT906_ALERT_3_C Large K Value in the Analysis of Variance ......     11.915 Check
PLAT906_ALERT_3_C Large K Value in the Analysis of Variance ......      2.670 Check

Alert level G
PLAT171_ALERT_4_G The CIF-Embedded .res File Contains EADP Records          1 Report
PLAT300_ALERT_4_G Atom Site Occupancy of N1         Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of C7         Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H7         Constrained at        0.5 Check
PLAT301_ALERT_3_G Main Residue  Disorder ..............(Resd  1  )        13% Note
PLAT410_ALERT_2_G Short Intra H...H Contact  H6       ..H7       .       2.02 Ang.
                                                   -x,-y,-z  =      5_555 Check
PLAT764_ALERT_4_G Overcomplete CIF Bond List Detected (Rep/Expd) .       1.22 Ratio
PLAT802_ALERT_4_G CIF Input Record(s) with more than 80 Characters          1 Info
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600          1 Note
PLAT933_ALERT_2_G Number of HKL-OMIT Records in Embedded .res File          1 Note
PLAT965_ALERT_2_G The SHELXL WEIGHT Optimisation has not Converged     Please Check
PLAT978_ALERT_2_G Number C-C Bonds with Positive Residual Density.          3 Info

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   4 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   7 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: X-AREA (Stoe & Cie, 2009); cell refinement: X-AREA (Stoe & Cie, 2009); data reduction: X-RED32 (Stoe & Cie, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2018/3(Sheldrick, 2015); molecular graphics: PLATON (Spek, 2020) and Mercury (Macrae et al., 2020); software used to prepare material for publication: SHELXL2018/3 (Sheldrick, 2015), PLATON (Spek, 2020) and publCIF (Westrip, 2010).

(E)-N,1-Bis(4-bromophenyl)methanimine

Crystal data

C13H9Br2N	Dx = 1.895 Mg m^−3
Mr = 339.03	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pccn	Cell parameters from 8006 reflections
a = 27.4096 (19) Å	θ = 1.5–26.1°
b = 7.3301 (5) Å	µ = 6.79 mm^−1
c = 5.9135 (3) Å	T = 173 K
V = 1188.11 (13) Å^3	Plate, colourless
Z = 4	0.45 × 0.33 × 0.13 mm
F(000) = 656

Data collection

STOE IPDS 2 diffractometer	1125 independent reflections
Radiation source: fine-focus sealed tube	911 reflections with I > 2σ(I)
Plane graphite monochromator	Rint = 0.075
φ + ω scans	θmax = 25.7°, θmin = 1.5°
Absorption correction: multi-scan (MULABS; Spek, 2020)	h = −33→33
Tmin = 0.411, Tmax = 1.000	k = −8→8
11334 measured reflections	l = −6→7

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.037	H-atom parameters constrained
wR(F^2) = 0.061	w = 1/[σ^2(Fo^2) + (0.0216P)^2 + 1.2266P] where P = (Fo^2 + 2Fc^2)/3
S = 1.09	(Δ/σ)max < 0.001
1125 reflections	Δρmax = 0.34 e Å^−3
71 parameters	Δρmin = −0.48 e Å^−3
0 restraints	Extinction correction: (SHELXL-2018/3; Sheldrick, 2015), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0018 (2)

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

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

	x	y	z	Uiso*/Ueq	Occ. (<1)
Br1	0.20539 (2)	0.04724 (6)	0.54116 (7)	0.03603 (15)
C1	0.06221 (13)	−0.0182 (5)	0.1208 (6)	0.0249 (7)
C2	0.10666 (12)	−0.0797 (4)	0.0348 (6)	0.0263 (8)
H2	0.107547	−0.136872	−0.109346	0.032*
C3	0.14960 (12)	−0.0586 (5)	0.1562 (6)	0.0269 (8)
H3	0.179825	−0.098688	0.095236	0.032*
C4	0.14765 (12)	0.0211 (5)	0.3664 (6)	0.0234 (7)
C5	0.10402 (12)	0.0822 (4)	0.4573 (6)	0.0241 (7)
H5	0.103375	0.137253	0.602660	0.029*
C6	0.06141 (12)	0.0622 (5)	0.3344 (6)	0.0247 (8)
H6	0.031373	0.103567	0.396099	0.030*
N1	0.0189 (6)	−0.0524 (16)	−0.013 (3)	0.0249 (7)	0.5
C7	0.0200 (8)	−0.0280 (19)	−0.026 (4)	0.0249 (7)	0.5
H7	0.023969	−0.080904	−0.171946	0.037*	0.5

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br1	0.02284 (19)	0.0454 (2)	0.0398 (2)	−0.00407 (19)	−0.00786 (17)	−0.0014 (2)
C1	0.0279 (12)	0.0196 (18)	0.0272 (15)	−0.0043 (13)	−0.0033 (11)	0.0045 (13)
C2	0.0331 (18)	0.0231 (19)	0.0229 (17)	−0.0017 (14)	−0.0001 (15)	−0.0011 (16)
C3	0.0257 (16)	0.028 (2)	0.0267 (19)	0.0032 (17)	0.0051 (14)	−0.0001 (17)
C4	0.0196 (15)	0.0229 (18)	0.0276 (18)	−0.0043 (14)	−0.0001 (13)	0.0045 (15)
C5	0.0287 (17)	0.0206 (19)	0.0229 (16)	−0.0023 (13)	0.0026 (15)	0.0005 (15)
C6	0.0191 (15)	0.0226 (19)	0.032 (2)	−0.0011 (15)	0.0016 (14)	−0.0002 (17)
N1	0.0279 (12)	0.0196 (18)	0.0272 (15)	−0.0043 (13)	−0.0033 (11)	0.0045 (13)
C7	0.0279 (12)	0.0196 (18)	0.0272 (15)	−0.0043 (13)	−0.0033 (11)	0.0045 (13)

Geometric parameters (Å, º)

Br1—C4	1.900 (3)	C3—H3	0.9500
C1—C6	1.394 (5)	C4—C5	1.385 (5)
C1—C2	1.395 (5)	C5—C6	1.383 (5)
C1—N1	1.448 (17)	C5—H5	0.9500
C1—C7	1.45 (2)	C6—H6	0.9500
C2—C3	1.387 (5)	N1—N1^i	1.30 (3)
C2—H2	0.9500	C7—C7^i	1.21 (4)
C3—C4	1.374 (5)	C7—H7	0.9500
C6—C1—C2	118.7 (3)	C3—C4—Br1	120.1 (3)
C6—C1—N1	123.8 (8)	C5—C4—Br1	118.4 (3)
C2—C1—N1	117.4 (7)	C6—C5—C4	119.4 (3)
C6—C1—C7	123.6 (9)	C6—C5—H5	120.3
C2—C1—C7	117.5 (9)	C4—C5—H5	120.3
C3—C2—C1	121.1 (3)	C5—C6—C1	120.5 (3)
C3—C2—H2	119.5	C5—C6—H6	119.8
C1—C2—H2	119.5	C1—C6—H6	119.8
C4—C3—C2	118.8 (3)	N1^i—N1—C1	119.0 (18)
C4—C3—H3	120.6	C7^i—C7—C1	123 (3)
C2—C3—H3	120.6	C7^i—C7—H7	118.3
C3—C4—C5	121.5 (3)	C1—C7—H7	118.3
C6—C1—C2—C3	−1.3 (5)	C4—C5—C6—C1	−0.1 (5)
N1—C1—C2—C3	−177.6 (5)	C2—C1—C6—C5	0.7 (5)
C7—C1—C2—C3	173.6 (6)	N1—C1—C6—C5	176.7 (6)
C1—C2—C3—C4	1.3 (5)	C7—C1—C6—C5	−173.9 (6)
C2—C3—C4—C5	−0.7 (5)	C6—C1—N1—N1^i	28.0 (17)
C2—C3—C4—Br1	178.5 (3)	C2—C1—N1—N1^i	−155.9 (13)
C3—C4—C5—C6	0.1 (5)	C6—C1—C7—C7^i	−2 (2)
Br1—C4—C5—C6	−179.1 (3)	C2—C1—C7—C7^i	−177.0 (15)

Symmetry code: (i) −x, −y, −z.

Hydrogen-bond geometry (Å, º)

Cg1 is the centroid of the C1–C6 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···Cg1^ii	0.95	2.81	3.535 (3)	134
C5—H5···Cg1^iii	0.95	2.78	3.494 (3)	133

Symmetry codes: (ii) x, −y−1/2, z−1/2; (iii) x, −y+1/2, z+1/2.