Crystallographic and spectroscopic characterization of two 1-phenyl-1H-imidazoles: 4-(1H-imidazol-1-yl)benzaldehyde and 1-(4-meth­oxy­phen­yl)-1H-imidazole

Two 1-phenyl-1H-imidazoles, 4-(1H-imidazol-1-yl)benzaldehyde and 1-(4-meth­oxy­phen­yl)-1H-imidazole, differ in the substituent para to the imidazole group on the arene ring. Both mol­ecules pack with different motifs via similar weak C—H...N/O inter­actions and differ with respect to the angles between the mean planes of the imidazole and arene rings.

Key indicators

Structure: I

• Single-crystal X-ray study
• T = 125 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.027
• wR factor = 0.079
• Data-to-parameter ratio = 12.5

Structure: II

• Single-crystal X-ray study
• T = 125 K
• Mean [sigma](C-C) = 0.001 Å
• R factor = 0.040
• wR factor = 0.119
• Data-to-parameter ratio = 22.5

checkCIF/PLATON results

No syntax errors found



Datablock: I


Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full value Low .      0.971 Why?
PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax < 18) ........       6.93 Note
PLAT911_ALERT_3_C Missing FCF Refl Between Thmin & STh/L=    0.600         21 Report
PLAT934_ALERT_3_C Number of (Iobs-Icalc)/Sigma(W) > 10 Outliers ..          1 Check

Alert level G
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600          2 Note
PLAT913_ALERT_3_G Missing # of Very Strong Reflections in FCF ....          2 Note
PLAT961_ALERT_5_G Dataset Contains no Negative Intensities .......     Please Check
PLAT978_ALERT_2_G Number C-C Bonds with Positive Residual Density.          7 Info

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   4 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   4 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
   5 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check




Datablock: II


Alert level G
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600         13 Note
PLAT978_ALERT_2_G Number C-C Bonds with Positive Residual Density.          9 Info

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

For both structures, data collection: APEX3 (Bruker, 2013); cell refinement: SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: SHELXT2018 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2017 (Sheldrick, 2015b); molecular graphics: SHELXTL2014 (Sheldrick, 2008); software used to prepare material for publication: SHELXTL2014 (Sheldrick, 2008), OLEX2 (Dolomanov et al., 2009), and Mercury (Macrae et al., 2020).

4-(1H-Imidazol-1-yl)benzaldehyde (I)

Crystal data

C10H8N2O	F(000) = 180
Mr = 172.18	Dx = 1.422 Mg m^−3
Monoclinic, P21	Cu Kα radiation, λ = 1.54178 Å
a = 3.7749 (2) Å	Cell parameters from 5426 reflections
b = 7.3711 (5) Å	θ = 3.1–71.6°
c = 14.4524 (9) Å	µ = 0.77 mm^−1
β = 91.096 (2)°	T = 125 K
V = 402.07 (4) Å^3	Plate, clear colourless
Z = 2	0.37 × 0.20 × 0.05 mm

Data collection

Bruker APEXII CCD diffractometer	1482 independent reflections
Radiation source: Cu IuS micro-focus source	1466 reflections with I > 2σ(I)
Detector resolution: 8.3333 pixels mm^-1	Rint = 0.029
φ and ω scans	θmax = 71.6°, θmin = 3.1°
Absorption correction: multi-scan (SADABS; Bruker, 2016)	h = −4→4
Tmin = 0.80, Tmax = 0.96	k = −8→7
5673 measured reflections	l = −17→16

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F^2 > 2σ(F^2)] = 0.027	w = 1/[σ^2(Fo^2) + (0.0495P)^2 + 0.0471P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.079	(Δ/σ)max < 0.001
S = 1.14	Δρmax = 0.19 e Å^−3
1482 reflections	Δρmin = −0.15 e Å^−3
119 parameters	Extinction correction: SHELXL2017 (Sheldrick, 2015b)
1 restraint	Extinction coefficient: 0.021 (6)
Primary atom site location: dual	Absolute structure: Flack x determined using 652 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013); Hooft y = 0.11(6) calculated with OLEX2 (Dolomanov et al., 2009).
Secondary atom site location: difference Fourier map	Absolute structure parameter: 0.09 (7)

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
O1	0.8970 (4)	0.9617 (2)	0.09534 (10)	0.0289 (4)
N1	0.3041 (4)	0.2861 (2)	0.33233 (10)	0.0166 (4)
N2	0.2148 (4)	0.1490 (2)	0.46723 (11)	0.0222 (4)
C1	0.8366 (5)	0.8021 (3)	0.07934 (13)	0.0230 (4)
H1A	0.889378	0.758391	0.019326	0.028*
C2	0.6890 (5)	0.6719 (3)	0.14516 (12)	0.0185 (4)
C3	0.6418 (5)	0.4920 (3)	0.11753 (13)	0.0203 (4)
H3A	0.698927	0.4571	0.056322	0.024*
C4	0.5120 (5)	0.3631 (3)	0.17851 (12)	0.0192 (4)
H4A	0.480518	0.240754	0.159434	0.023*
C5	0.4286 (4)	0.4165 (3)	0.26824 (12)	0.0169 (4)
C6	0.4704 (4)	0.5971 (3)	0.29652 (12)	0.0183 (4)
H6A	0.409116	0.632564	0.357352	0.022*
C7	0.6015 (5)	0.7236 (3)	0.23531 (13)	0.0199 (4)
H7A	0.632366	0.846022	0.254394	0.024*
C8	0.1451 (4)	0.1207 (3)	0.31214 (12)	0.0191 (4)
H8A	0.086412	0.073743	0.25258	0.023*
C9	0.0906 (5)	0.0395 (3)	0.39529 (13)	0.0212 (4)
H9A	−0.017271	−0.075833	0.403072	0.025*
C10	0.3399 (5)	0.2943 (3)	0.42704 (13)	0.0204 (4)
H10A	0.443164	0.393702	0.45957	0.025*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0395 (9)	0.0225 (9)	0.0249 (7)	−0.0053 (6)	0.0026 (6)	0.0022 (6)
N1	0.0195 (7)	0.0148 (9)	0.0154 (7)	0.0001 (6)	−0.0004 (5)	0.0002 (6)
N2	0.0268 (8)	0.0210 (10)	0.0188 (7)	−0.0002 (6)	0.0009 (6)	0.0014 (6)
C1	0.0245 (9)	0.0236 (12)	0.0209 (9)	−0.0008 (8)	−0.0004 (7)	0.0000 (8)
C2	0.0179 (8)	0.0201 (11)	0.0175 (8)	0.0005 (7)	−0.0013 (7)	0.0002 (7)
C3	0.0212 (9)	0.0230 (11)	0.0166 (9)	0.0020 (7)	0.0012 (7)	−0.0018 (7)
C4	0.0230 (9)	0.0166 (11)	0.0180 (8)	−0.0005 (7)	−0.0001 (7)	−0.0021 (7)
C5	0.0151 (8)	0.0176 (10)	0.0180 (8)	0.0009 (7)	−0.0018 (6)	0.0007 (7)
C6	0.0212 (8)	0.0175 (10)	0.0164 (8)	0.0015 (7)	0.0006 (7)	−0.0021 (7)
C7	0.0213 (9)	0.0162 (10)	0.0221 (10)	0.0002 (7)	−0.0015 (7)	−0.0017 (7)
C8	0.0202 (8)	0.0168 (10)	0.0203 (8)	−0.0005 (7)	−0.0009 (6)	−0.0027 (7)
C9	0.0219 (9)	0.0187 (11)	0.0229 (9)	0.0004 (7)	0.0007 (7)	0.0016 (7)
C10	0.0243 (9)	0.0207 (11)	0.0163 (9)	0.0005 (7)	−0.0013 (7)	−0.0012 (7)

Geometric parameters (Å, º)

O1—C1	1.219 (3)	C3—H3A	0.9500
N1—C10	1.374 (2)	C4—C5	1.397 (2)
N1—C8	1.388 (2)	C4—H4A	0.9500
N1—C5	1.421 (2)	C5—C6	1.401 (3)
N2—C10	1.311 (2)	C6—C7	1.383 (3)
N2—C9	1.391 (2)	C6—H6A	0.9500
C1—C2	1.469 (2)	C7—H7A	0.9500
C1—H1A	0.9500	C8—C9	1.362 (3)
C2—C3	1.395 (3)	C8—H8A	0.9500
C2—C7	1.403 (2)	C9—H9A	0.9500
C3—C4	1.391 (3)	C10—H10A	0.9500
C10—N1—C8	106.39 (15)	C4—C5—N1	119.84 (17)
C10—N1—C5	126.28 (15)	C6—C5—N1	119.32 (16)
C8—N1—C5	127.19 (15)	C7—C6—C5	119.59 (17)
C10—N2—C9	105.21 (15)	C7—C6—H6A	120.2
O1—C1—C2	125.41 (17)	C5—C6—H6A	120.2
O1—C1—H1A	117.3	C6—C7—C2	120.28 (18)
C2—C1—H1A	117.3	C6—C7—H7A	119.9
C3—C2—C7	119.54 (17)	C2—C7—H7A	119.9
C3—C2—C1	118.92 (15)	C9—C8—N1	105.83 (16)
C7—C2—C1	121.53 (17)	C9—C8—H8A	127.1
C4—C3—C2	120.81 (16)	N1—C8—H8A	127.1
C4—C3—H3A	119.6	C8—C9—N2	110.49 (18)
C2—C3—H3A	119.6	C8—C9—H9A	124.8
C3—C4—C5	118.95 (17)	N2—C9—H9A	124.8
C3—C4—H4A	120.5	N2—C10—N1	112.07 (16)
C5—C4—H4A	120.5	N2—C10—H10A	124.0
C4—C5—C6	120.84 (16)	N1—C10—H10A	124.0
O1—C1—C2—C3	−178.55 (18)	N1—C5—C6—C7	178.08 (15)
O1—C1—C2—C7	0.2 (3)	C5—C6—C7—C2	0.6 (2)
C7—C2—C3—C4	−0.6 (3)	C3—C2—C7—C6	0.2 (3)
C1—C2—C3—C4	178.21 (16)	C1—C2—C7—C6	−178.52 (16)
C2—C3—C4—C5	0.1 (3)	C10—N1—C8—C9	0.62 (19)
C3—C4—C5—C6	0.7 (3)	C5—N1—C8—C9	176.67 (16)
C3—C4—C5—N1	−178.42 (15)	N1—C8—C9—N2	−0.6 (2)
C10—N1—C5—C4	153.02 (17)	C10—N2—C9—C8	0.4 (2)
C8—N1—C5—C4	−22.3 (2)	C9—N2—C10—N1	0.0 (2)
C10—N1—C5—C6	−26.2 (3)	C8—N1—C10—N2	−0.4 (2)
C8—N1—C5—C6	158.54 (16)	C5—N1—C10—N2	−176.52 (16)
C4—C5—C6—C7	−1.1 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8A···O1^i	0.95	2.51	3.458 (2)	176
C10—H10A···N2^ii	0.95	2.51	3.449 (2)	173

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

1-(4-Methoxyphenyl)-1H-imidazole (II)

Crystal data

C10H10N2O	F(000) = 368
Mr = 174.20	Dx = 1.318 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 8.5663 (12) Å	Cell parameters from 8588 reflections
b = 11.2143 (16) Å	θ = 2.4–30.4°
c = 9.1635 (13) Å	µ = 0.09 mm^−1
β = 94.448 (2)°	T = 125 K
V = 877.6 (2) Å^3	Plate, colourless
Z = 4	0.40 × 0.25 × 0.15 mm

Data collection

Bruker APEXII CCD diffractometer	2678 independent reflections
Radiation source: sealed X-ray tube, Bruker APEXII CCD	2332 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.031
Detector resolution: 8.3333 pixels mm^-1	θmax = 30.6°, θmin = 2.4°
φ and ω scans	h = −12→12
Absorption correction: multi-scan (SADABS; Bruker, 2016)	k = −16→15
Tmin = 0.92, Tmax = 0.99	l = −13→13
21397 measured reflections

Refinement

Refinement on F^2	Primary atom site location: dual
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.119	H-atom parameters constrained
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0687P)^2 + 0.1966P] where P = (Fo^2 + 2Fc^2)/3
2678 reflections	(Δ/σ)max < 0.001
119 parameters	Δρmax = 0.35 e Å^−3
0 restraints	Δρmin = −0.29 e Å^−3

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
N1	0.50111 (8)	0.64826 (6)	0.27442 (7)	0.01696 (16)
N2	0.35189 (9)	0.60120 (7)	0.07295 (8)	0.02110 (17)
O1	0.98420 (8)	0.63969 (6)	0.71768 (7)	0.02769 (18)
C1	1.02429 (11)	0.53203 (10)	0.79493 (10)	0.0289 (2)
H1A	1.108753	0.547969	0.87077	0.043*
H1B	1.059244	0.472373	0.726426	0.043*
H1C	0.932403	0.501862	0.840608	0.043*
C2	0.86571 (10)	0.63397 (8)	0.60922 (9)	0.02084 (18)
C3	0.81994 (11)	0.74301 (8)	0.54587 (10)	0.02479 (19)
H3A	0.870761	0.814315	0.579384	0.03*
C4	0.70105 (11)	0.74809 (8)	0.43457 (9)	0.02198 (18)
H4A	0.670793	0.822403	0.391376	0.026*
C5	0.62626 (10)	0.64337 (7)	0.38651 (9)	0.01708 (17)
C6	0.67205 (10)	0.53468 (7)	0.44827 (9)	0.01901 (17)
H6A	0.621215	0.463503	0.414318	0.023*
C7	0.79220 (10)	0.52919 (8)	0.55986 (9)	0.02071 (18)
H7A	0.823565	0.454653	0.601777	0.025*
C8	0.37965 (10)	0.72974 (7)	0.26290 (9)	0.01978 (18)
H8A	0.362414	0.793692	0.327719	0.024*
C9	0.28976 (10)	0.69928 (8)	0.13921 (9)	0.02107 (18)
H9A	0.197198	0.739844	0.10349	0.025*
C10	0.47846 (10)	0.57358 (7)	0.15758 (9)	0.01911 (18)
H10A	0.545959	0.509019	0.139087	0.023*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0198 (3)	0.0156 (3)	0.0153 (3)	0.0015 (2)	0.0003 (2)	−0.0014 (2)
N2	0.0226 (4)	0.0219 (4)	0.0183 (3)	0.0020 (3)	−0.0011 (3)	−0.0016 (3)
O1	0.0249 (3)	0.0327 (4)	0.0239 (3)	−0.0069 (3)	−0.0077 (3)	0.0039 (3)
C1	0.0249 (4)	0.0389 (5)	0.0222 (4)	−0.0024 (4)	−0.0028 (3)	0.0082 (4)
C2	0.0194 (4)	0.0251 (4)	0.0178 (4)	−0.0035 (3)	0.0003 (3)	0.0010 (3)
C3	0.0271 (4)	0.0204 (4)	0.0260 (4)	−0.0055 (3)	−0.0037 (3)	−0.0010 (3)
C4	0.0264 (4)	0.0162 (4)	0.0228 (4)	−0.0015 (3)	−0.0013 (3)	0.0004 (3)
C5	0.0188 (4)	0.0176 (4)	0.0148 (3)	−0.0004 (3)	0.0009 (3)	−0.0006 (3)
C6	0.0205 (4)	0.0167 (4)	0.0195 (4)	−0.0014 (3)	−0.0001 (3)	−0.0001 (3)
C7	0.0214 (4)	0.0205 (4)	0.0200 (4)	−0.0013 (3)	−0.0001 (3)	0.0031 (3)
C8	0.0231 (4)	0.0166 (4)	0.0197 (4)	0.0034 (3)	0.0024 (3)	−0.0010 (3)
C9	0.0211 (4)	0.0209 (4)	0.0211 (4)	0.0037 (3)	0.0005 (3)	0.0011 (3)
C10	0.0221 (4)	0.0181 (4)	0.0170 (3)	0.0018 (3)	0.0004 (3)	−0.0031 (3)

Geometric parameters (Å, º)

N1—C10	1.3612 (10)	C3—C4	1.3854 (12)
N1—C8	1.3827 (10)	C3—H3A	0.9500
N1—C5	1.4271 (10)	C4—C5	1.3928 (11)
N2—C10	1.3200 (10)	C4—H4A	0.9500
N2—C9	1.3828 (11)	C5—C6	1.3876 (11)
O1—C2	1.3658 (10)	C6—C7	1.3947 (11)
O1—C1	1.4279 (12)	C6—H6A	0.9500
C1—H1A	0.9800	C7—H7A	0.9500
C1—H1B	0.9800	C8—C9	1.3634 (11)
C1—H1C	0.9800	C8—H8A	0.9500
C2—C7	1.3920 (12)	C9—H9A	0.9500
C2—C3	1.3967 (12)	C10—H10A	0.9500
C10—N1—C8	106.62 (7)	C5—C4—H4A	120.3
C10—N1—C5	126.57 (7)	C6—C5—C4	120.21 (8)
C8—N1—C5	126.81 (7)	C6—C5—N1	120.01 (7)
C10—N2—C9	104.78 (7)	C4—C5—N1	119.78 (7)
C2—O1—C1	117.23 (7)	C5—C6—C7	120.46 (7)
O1—C1—H1A	109.5	C5—C6—H6A	119.8
O1—C1—H1B	109.5	C7—C6—H6A	119.8
H1A—C1—H1B	109.5	C2—C7—C6	119.38 (8)
O1—C1—H1C	109.5	C2—C7—H7A	120.3
H1A—C1—H1C	109.5	C6—C7—H7A	120.3
H1B—C1—H1C	109.5	C9—C8—N1	105.73 (7)
O1—C2—C7	124.61 (8)	C9—C8—H8A	127.1
O1—C2—C3	115.48 (8)	N1—C8—H8A	127.1
C7—C2—C3	119.91 (8)	C8—C9—N2	110.64 (7)
C4—C3—C2	120.57 (8)	C8—C9—H9A	124.7
C4—C3—H3A	119.7	N2—C9—H9A	124.7
C2—C3—H3A	119.7	N2—C10—N1	112.23 (7)
C3—C4—C5	119.47 (8)	N2—C10—H10A	123.9
C3—C4—H4A	120.3	N1—C10—H10A	123.9
C1—O1—C2—C7	−6.43 (13)	N1—C5—C6—C7	−178.75 (7)
C1—O1—C2—C3	174.10 (8)	O1—C2—C7—C6	179.88 (8)
O1—C2—C3—C4	179.87 (8)	C3—C2—C7—C6	−0.68 (13)
C7—C2—C3—C4	0.38 (14)	C5—C6—C7—C2	0.19 (13)
C2—C3—C4—C5	0.41 (14)	C10—N1—C8—C9	0.16 (9)
C3—C4—C5—C6	−0.91 (13)	C5—N1—C8—C9	179.98 (7)
C3—C4—C5—N1	178.46 (7)	N1—C8—C9—N2	−0.15 (10)
C10—N1—C5—C6	−44.15 (12)	C10—N2—C9—C8	0.07 (10)
C8—N1—C5—C6	136.07 (9)	C9—N2—C10—N1	0.03 (10)
C10—N1—C5—C4	136.49 (9)	C8—N1—C10—N2	−0.12 (10)
C8—N1—C5—C4	−43.30 (12)	C5—N1—C10—N2	−179.94 (7)
C4—C5—C6—C7	0.61 (13)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8A···N2^i	0.95	2.55	3.4391 (11)	157
C9—H9A···O1^ii	0.95	2.56	3.3048 (11)	136
C10—H10A···N2^iii	0.95	2.52	3.3004 (11)	140

Symmetry codes: (i) x, −y+3/2, z+1/2; (ii) x−1, −y+3/2, z−1/2; (iii) −x+1, −y+1, −z.