2,2'-Diamino­dibenzyl: a rare case of crystallographically non-compliant mol­ecular symmetry

The title compound, C₁₄H₁₆N₂, adopts a trans-planar conformation. However, the mol­ecule, which possesses C_i point group symmetry, crystallizes in the non-centrosymmetric space group P2₁2₁2₁. In the crystal structure, the mol­ecular symmetry is only approximately retained. The crystal packing is predominantly stabilized by N—H...N hydrogen bonds. Weak C—H...π inter­actions also contribute to the stability.

Key indicators

• Single-crystal X-ray study
• T = 292 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.040
• wR factor = 0.102
• Data-to-parameter ratio = 9.0

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT420_ALERT_2_C D-H Without Acceptor       N1     -   H1A    ...          ?
PLAT420_ALERT_2_C D-H Without Acceptor       N2     -   H2A    ...          ?
PLAT480_ALERT_4_C Long H...A H-Bond Reported H11    ..  CG2     ..       2.92 Ang.

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.43
           From the CIF: _reflns_number_total               1456
           Count of symmetry unique reflns         1530
           Completeness (_total/calc)             95.16%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present         no

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

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 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
   2 ALERT type 4 Improvement, methodology, query or suggestion

---

Computing details

Data collection: SMART (Bruker, 1998); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: WinGX (Farrugia, 1999) and PARST (Nardelli, 1995).

2,2'-Diaminodibenzyl

Crystal data

C14H16N2	F(000) = 456
Mr = 212.29	Dx = 1.237 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 5764 reflections
a = 5.4716 (4) Å	θ = 5–54°
b = 12.480 (1) Å	µ = 0.07 mm^−1
c = 16.695 (1) Å	T = 292 K
V = 1140.0 (2) Å^3	Block, colourless
Z = 4	0.51 × 0.24 × 0.15 mm

Data collection

Bruker SMART CCD area-detector diffractometer	1456 independent reflections
Radiation source: fine-focus sealed tube	1344 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.021
ω scans	θmax = 27.4°, θmin = 2.0°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −7→6
Tmin = 0.97, Tmax = 0.98	k = −16→14
9109 measured reflections	l = −21→21

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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.103	H atoms treated by a mixture of independent and constrained refinement
S = 1.11	w = 1/[σ^2(Fo^2) + (0.0596P)^2 + 0.1255P] where P = (Fo^2 + 2Fc^2)/3
1456 reflections	(Δ/σ)max < 0.001
161 parameters	Δρmax = 0.16 e Å^−3
0 restraints	Δρmin = −0.28 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.

Weighted least-squares planes through the starred atoms (Nardelli, Musatti, Domiano & Andreetti Ric·Sci.(1965),15(II—A),807). Equation of the plane: m1*X+m2*Y+m3*Z=d

Plane 1 m1 = 0.64645(0.00000) m2 = 0.24391(0.00000) m3 = -0.72292(0.00000) D = -5.83995(0.00010) Atom d s d/s (d/s)**2 C1 * 0.0148 0.0017 8.598 73.930 C2 * 0.0013 0.0017 0.736 0.542 C3 * -0.0063 0.0019 - 3.319 11.019 C4 * -0.0082 0.0019 - 4.220 17.812 C5 * -0.0014 0.0019 - 0.732 0.535 C6 * 0.0132 0.0019 7.096 50.352 C7 * 0.0373 0.0017 21.324 454.720 C8 * 0.0288 0.0017 16.926 286.475 C9 * 0.0416 0.0017 24.316 591.280 C10 * 0.0428 0.0017 25.127 631.348 C11 * 0.0127 0.0019 6.592 43.449 C12 * -0.0125 0.0021 - 5.985 35.823 C13 * 0.0039 0.0021 1.854 3.438 C14 * 0.0311 0.0019 16.380 268.311 N1 * 0.0475 0.0018 25.910 671.315 N2 * 0.0253 0.0018 14.018 196.493 H3 * -0.0100 0.0001 - 99.798 9959.655 H4 * -0.0143 0.0001 - 142.560 20323.371 H5 * -0.0065 0.0001 - 65.219 4253.479 H6 * 0.0221 0.0001 221.490 49057.891 H11 * 0.0096 0.0001 96.082 9231.792 H12 * -0.0405 0.0001 - 405.346 164305.750 H13 * -0.0031 0.0001 - 31.409 986.525 H14 * 0.0425 0.0001 425.081 180693.703 ============ Sum((d/s)**2) for starred atoms 442149.000 Chi-squared at 95% for 21 degrees of freedom: 32.70 The group of atoms deviates significantly from planarity

Plane 2 m1 = -0.53086(0.02439) m2 = -0.83272(0.01768) m3 = 0.15736(0.02553) D = -7.83991(0.46080) Atom d s d/s (d/s)**2 N1 * 0.0000 0.0017 0.000 0.000 H1A * 0.0000 0.0215 0.000 0.000 H1B * 0.0000 0.0236 0.000 0.000 C2 1.0605 0.0017 638.401 407555.531 ============ Sum((d/s)**2) for starred atoms 0.000

Plane 3 m1 = -0.57979(0.02078) m2 = -0.78869(0.01857) m3 = 0.20447(0.02790) D = -5.47071(0.46131) Atom d s d/s (d/s)**2 N2 * 0.0000 0.0016 0.000 0.000 H2A * 0.0000 0.0242 0.000 0.000 H2B * 0.0000 0.0227 0.000 0.000 C10 - 0.9693 0.0017 - 580.761 337283.875 ============ Sum((d/s)**2) for starred atoms 0.000

Plane 4 m1 = 0.63926(0.00000) m2 = 0.24169(0.00000) m3 = -0.73002(0.00000) D = -5.92163(0.00026) Atom d s d/s (d/s)**2 C1 * -0.0059 0.0017 - 3.415 11.664 C2 * -0.0106 0.0017 - 6.211 38.582 C3 * -0.0038 0.0019 - 2.023 4.093 C4 * -0.0001 0.0019 - 0.075 0.006 C5 * -0.0020 0.0019 - 1.010 1.020 C6 * -0.0016 0.0019 - 0.853 0.728 H3 * -0.0017 0.0001 - 16.899 285.572 H4 * 0.0034 0.0001 33.541 1125.019 H5 * -0.0033 0.0001 - 33.413 1116.443 H6 * 0.0017 0.0001 16.740 280.234 N1 * 0.0302 0.0018 16.446 270.470 C7 * 0.0011 0.0017 0.634 0.402 H1A -0.5216 0.0225 - 23.234 539.823 H1B -0.1541 0.0230 - 6.706 44.965 ============ Sum((d/s)**2) for starred atoms 3134.232 Chi-squared at 95% for 9 degrees of freedom: 16.90 The group of atoms deviates significantly from planarity

Plane 5 m1 = 0.66112(0.00000) m2 = 0.25542(0.00000) m3 = -0.70547(0.00000) D = -5.37701(0.00041) Atom d s d/s (d/s)**2 C9 * -0.0203 0.0017 - 11.835 140.075 C10 * -0.0061 0.0017 - 3.559 12.664 C11 * -0.0010 0.0019 - 0.533 0.284 C12 * -0.0038 0.0021 - 1.825 3.331 C13 * 0.0003 0.0021 0.155 0.024 C14 * -0.0075 0.0019 - 3.928 15.433 H11 * 0.0043 0.0001 43.051 1853.378 H12 * -0.0085 0.0001 - 84.650 7165.545 H13 * 0.0083 0.0001 83.485 6969.692 H14 * -0.0041 0.0001 - 40.915 1674.016 N2 * -0.0462 0.0018 - 25.642 657.534 C8 * -0.0712 0.0017 - 41.815 1748.531 H2A 0.4349 0.0250 17.411 303.134 H2B 0.1355 0.0219 6.196 38.394 ============ Sum((d/s)**2) for starred atoms 20240.506 Chi-squared at 95% for 9 degrees of freedom: 16.90 The group of atoms deviates significantly from planarity

Dihedral angles formed by LSQ-planes Plane - plane angle (s.u.) angle (s.u.) 1 2 48.70 (1.36) 131.30 (1.36) 1 3 44.36 (1.42) 135.64 (1.42) 1 4 0.59 (0.00) 179.41 (0.00) 1 5 1.46 (0.00) 178.54 (0.00) 2 3 4.64 (1.99) 175.36 (1.99) 2 4 49.04 (1.32) 130.96 (1.32) 2 5 47.57 (1.43) 132.43 (1.43) 3 4 44.72 (1.53) 135.28 (1.53) 3 5 43.20 (1.46) 136.80 (1.46) 4 5 2.04 (0.00) 177.96 (0.00)

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
N1	−0.1909 (3)	0.97722 (13)	0.67049 (11)	0.0396 (4)
N2	0.6995 (3)	0.62302 (12)	0.84395 (11)	0.0396 (4)
C1	−0.0114 (3)	0.79906 (13)	0.68086 (10)	0.0301 (4)
C2	−0.1873 (3)	0.86849 (13)	0.64793 (10)	0.0312 (4)
C3	−0.3518 (4)	0.83089 (15)	0.59086 (11)	0.0374 (4)
H3	−0.4671	0.8773	0.5691	0.045*
C4	−0.3454 (4)	0.72499 (15)	0.56621 (11)	0.0403 (5)
H4	−0.4560	0.7005	0.5281	0.048*
C5	−0.1748 (4)	0.65592 (14)	0.59822 (11)	0.0389 (4)
H5	−0.1702	0.5847	0.5820	0.047*
C6	−0.0101 (4)	0.69337 (14)	0.65473 (10)	0.0351 (4)
H6	0.1049	0.6463	0.6758	0.042*
C7	0.1670 (3)	0.84215 (13)	0.74214 (10)	0.0320 (4)
H7A	0.0746	0.8719	0.7865	0.038*
H7B	0.2583	0.9003	0.7179	0.038*
C8	0.3472 (3)	0.76105 (13)	0.77522 (10)	0.0315 (4)
H8A	0.2553	0.7027	0.7989	0.038*
H8B	0.4397	0.7317	0.7308	0.038*
C9	0.5258 (3)	0.80222 (14)	0.83690 (10)	0.0298 (4)
C10	0.6982 (3)	0.73072 (13)	0.86927 (10)	0.0319 (4)
C11	0.8605 (4)	0.76520 (16)	0.92803 (11)	0.0395 (4)
H11	0.9735	0.7174	0.9494	0.047*
C12	0.8549 (4)	0.86984 (16)	0.95487 (12)	0.0444 (5)
H12	0.9631	0.8921	0.9945	0.053*
C13	0.6898 (4)	0.94132 (15)	0.92315 (12)	0.0437 (5)
H13	0.6870	1.0120	0.9408	0.052*
C14	0.5275 (4)	0.90715 (15)	0.86472 (11)	0.0378 (4)
H14	0.4164	0.9559	0.8435	0.045*
H1A	−0.168 (4)	0.9845 (17)	0.7240 (13)	0.049 (6)*
H1B	−0.328 (4)	1.0116 (19)	0.6548 (13)	0.052 (6)*
H2A	0.673 (5)	0.6138 (19)	0.7923 (15)	0.064 (7)*
H2B	0.829 (4)	0.5862 (18)	0.8584 (12)	0.048 (6)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0368 (9)	0.0328 (8)	0.0494 (10)	0.0043 (7)	−0.0068 (8)	0.0021 (7)
N2	0.0349 (9)	0.0326 (8)	0.0512 (10)	0.0073 (7)	−0.0043 (8)	0.0027 (7)
C1	0.0282 (9)	0.0322 (8)	0.0299 (8)	−0.0008 (7)	0.0018 (7)	0.0028 (7)
C2	0.0279 (9)	0.0318 (9)	0.0339 (8)	−0.0016 (7)	0.0024 (8)	0.0045 (7)
C3	0.0312 (9)	0.0441 (10)	0.0369 (9)	−0.0002 (9)	−0.0037 (8)	0.0066 (7)
C4	0.0377 (10)	0.0478 (11)	0.0353 (9)	−0.0102 (10)	−0.0048 (8)	−0.0010 (8)
C5	0.0451 (11)	0.0338 (9)	0.0380 (9)	−0.0071 (9)	0.0020 (9)	−0.0019 (7)
C6	0.0371 (10)	0.0329 (9)	0.0355 (9)	0.0007 (8)	0.0004 (8)	0.0044 (7)
C7	0.0299 (9)	0.0285 (8)	0.0375 (9)	0.0004 (8)	−0.0032 (8)	0.0017 (7)
C8	0.0299 (9)	0.0292 (8)	0.0354 (9)	0.0014 (8)	−0.0015 (7)	0.0008 (7)
C9	0.0266 (8)	0.0317 (9)	0.0312 (8)	−0.0008 (7)	0.0011 (7)	0.0026 (7)
C10	0.0282 (8)	0.0337 (9)	0.0338 (8)	−0.0004 (8)	0.0045 (7)	0.0055 (7)
C11	0.0322 (9)	0.0467 (11)	0.0397 (10)	0.0010 (9)	−0.0049 (8)	0.0103 (8)
C12	0.0431 (11)	0.0514 (12)	0.0387 (9)	−0.0082 (10)	−0.0092 (9)	0.0006 (8)
C13	0.0491 (11)	0.0358 (10)	0.0462 (10)	−0.0039 (10)	−0.0031 (10)	−0.0060 (8)
C14	0.0380 (10)	0.0332 (9)	0.0422 (10)	0.0041 (9)	−0.0038 (9)	0.0006 (8)

Geometric parameters (Å, º)

N1—C2	1.408 (2)	C7—C8	1.517 (2)
N1—H1A	0.91 (2)	C7—H7A	0.9700
N1—H1B	0.90 (2)	C7—H7B	0.9700
N2—C10	1.409 (2)	C8—C9	1.510 (2)
N2—H2A	0.88 (2)	C8—H8A	0.9700
N2—H2B	0.88 (2)	C8—H8B	0.9700
C1—C6	1.389 (2)	C9—C14	1.389 (2)
C1—C2	1.407 (2)	C9—C10	1.406 (2)
C1—C7	1.513 (2)	C10—C11	1.391 (3)
C2—C3	1.392 (2)	C11—C12	1.381 (3)
C3—C4	1.385 (3)	C11—H11	0.9300
C3—H3	0.9300	C12—C13	1.376 (3)
C4—C5	1.378 (3)	C12—H12	0.9300
C4—H4	0.9300	C13—C14	1.386 (3)
C5—C6	1.386 (3)	C13—H13	0.9300
C5—H5	0.9300	C14—H14	0.9300
C6—H6	0.9300
C2—N1—H1A	111.0 (13)	C1—C7—H7B	108.4
C2—N1—H1B	113.0 (15)	C8—C7—H7B	108.4
H1A—N1—H1B	111 (2)	H7A—C7—H7B	107.5
C10—N2—H2A	114.6 (16)	C9—C8—C7	116.23 (14)
C10—N2—H2B	114.8 (15)	C9—C8—H8A	108.2
H2A—N2—H2B	110 (2)	C7—C8—H8A	108.2
C6—C1—C2	117.75 (17)	C9—C8—H8B	108.2
C6—C1—C7	123.13 (16)	C7—C8—H8B	108.2
C2—C1—C7	119.12 (14)	H8A—C8—H8B	107.4
C3—C2—C1	120.14 (15)	C14—C9—C10	117.72 (16)
C3—C2—N1	119.93 (16)	C14—C9—C8	123.57 (16)
C1—C2—N1	119.88 (16)	C10—C9—C8	118.70 (15)
C4—C3—C2	120.56 (18)	C11—C10—C9	120.18 (17)
C4—C3—H3	119.7	C11—C10—N2	120.20 (17)
C2—C3—H3	119.7	C9—C10—N2	119.58 (16)
C5—C4—C3	119.94 (18)	C12—C11—C10	120.47 (18)
C5—C4—H4	120.0	C12—C11—H11	119.8
C3—C4—H4	120.0	C10—C11—H11	119.8
C4—C5—C6	119.56 (17)	C13—C12—C11	120.19 (18)
C4—C5—H5	120.2	C13—C12—H12	119.9
C6—C5—H5	120.2	C11—C12—H12	119.9
C5—C6—C1	122.04 (18)	C12—C13—C14	119.48 (18)
C5—C6—H6	119.0	C12—C13—H13	120.3
C1—C6—H6	119.0	C14—C13—H13	120.3
C1—C7—C8	115.37 (14)	C13—C14—C9	121.96 (18)
C1—C7—H7A	108.4	C13—C14—H14	119.0
C8—C7—H7A	108.4	C9—C14—H14	119.0
C6—C1—C2—C3	−0.3 (3)	C7—C8—C9—C14	1.4 (2)
C7—C1—C2—C3	179.37 (15)	C7—C8—C9—C10	−179.61 (14)
C6—C1—C2—N1	−177.87 (17)	C14—C9—C10—C11	1.0 (3)
C7—C1—C2—N1	1.8 (2)	C8—C9—C10—C11	−178.01 (15)
C1—C2—C3—C4	0.4 (3)	C14—C9—C10—N2	178.69 (16)
N1—C2—C3—C4	177.92 (18)	C8—C9—C10—N2	−0.3 (2)
C2—C3—C4—C5	−0.1 (3)	C9—C10—C11—C12	−0.3 (3)
C3—C4—C5—C6	−0.3 (3)	N2—C10—C11—C12	−177.98 (18)
C4—C5—C6—C1	0.3 (3)	C10—C11—C12—C13	−0.6 (3)
C2—C1—C6—C5	0.0 (3)	C11—C12—C13—C14	0.7 (3)
C7—C1—C6—C5	−179.70 (16)	C12—C13—C14—C9	0.0 (3)
C6—C1—C7—C8	−1.2 (2)	C10—C9—C14—C13	−0.9 (3)
C2—C1—C7—C8	179.08 (15)	C8—C9—C14—C13	178.08 (17)
C1—C7—C8—C9	−179.60 (15)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1B···N2^i	0.90 (2)	2.46 (2)	3.334 (2)	162 (2)
N2—H2B···N1^ii	0.88 (2)	2.45 (2)	3.255 (2)	153 (2)
C7—H7A···Cg2^iii	0.97	2.81	3.654 (2)	145
C8—H8B···Cg1^iv	0.97	2.78	3.624 (2)	147
C4—H4···Cg1^v	0.93	2.85	3.657 (2)	139
C11—H11···Cg2^vi	0.93	2.92	3.678 (2)	139

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