2,2′-Bis(2-nitro­benzylidene)pyridine-2,6-dicarbohydrazide

The title mol­ecule, C₂₁H₁₅N₇O₆, has crystallographic twofold symmetry. In the crystal structure, inter­molecular N—H...O hydrogen bonds [H...O = 2.125 (17) Å] link the mol­ecules, forming one-dimensional chains along [001].

Key indicators

• Single-crystal X-ray study
• T = 292 K
• Mean [sigma](C-C) = 0.002 Å
• Disorder in main residue
• R factor = 0.056
• wR factor = 0.132
• Data-to-parameter ratio = 13.9

checkCIF/PLATON results

No syntax errors found



Alert level C
RINTA01_ALERT_3_C  The value of Rint is greater than 0.10
            Rint given   0.128
PLAT020_ALERT_3_C The value of Rint is greater than 0.10 .........       0.13
PLAT220_ALERT_2_C Large Non-Solvent    O     Ueq(max)/Ueq(min) ...       3.38 Ratio
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         N4
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.02
PLAT301_ALERT_3_C Main Residue  Disorder .........................      11.00 Perc.
PLAT482_ALERT_4_C Small D-H..A Angle Rep for C7     ..  N3      ..      99.60 Deg.
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          1
              C21 H15 N7 O6

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 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
   2 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: SMART (Bruker, 2001); 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: PLATON (Spek, 2003); software used to prepare material for publication: PLATON.

bis(2-Nitrobenzaldehyde)-2,6-dipicolinoyhydrazone

Crystal data

C21H15N7O6	F(000) = 952
Mr = 461.40	Dx = 1.486 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 1723 reflections
a = 19.889 (3) Å	θ = 3.1–25.4°
b = 12.5106 (17) Å	µ = 0.11 mm^−1
c = 8.3010 (11) Å	T = 292 K
β = 92.861 (3)°	Needle, yellow
V = 2062.9 (5) Å^3	0.20 × 0.10 × 0.06 mm
Z = 4

Data collection

Bruker SMART APEX CCD diffractometer	1578 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.129
Graphite monochromator	θmax = 28.0°, θmin = 1.9°
φ and ω scans	h = −26→26
9263 measured reflections	k = −16→16
2454 independent reflections	l = −10→10

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)] = 0.056	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.133	H atoms treated by a mixture of independent and constrained refinement
S = 0.92	w = 1/[σ^2(Fo^2) + (0.0515P)^2] where P = (Fo^2 + 2Fc^2)/3
2454 reflections	(Δ/σ)max = 0.001
177 parameters	Δρmax = 0.31 e Å^−3
4 restraints	Δρmin = −0.31 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.

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	Occ. (<1)
C1	0.0000	0.18506 (18)	−0.2500	0.0439 (6)
H1	0.0000	0.1107	−0.2500	0.053*
C2	0.03481 (8)	0.24050 (13)	−0.1294 (2)	0.0391 (4)
H2	0.0579	0.2046	−0.0456	0.047*
C3	0.03450 (7)	0.35141 (12)	−0.13612 (18)	0.0299 (4)
C4	0.07350 (8)	0.41581 (12)	−0.0099 (2)	0.0318 (4)
C5	0.12562 (8)	0.67997 (13)	−0.0089 (2)	0.0366 (4)
H5	0.1016	0.6994	−0.1034	0.044*
C6	0.16581 (8)	0.75979 (13)	0.0840 (2)	0.0359 (4)
C7	0.21171 (9)	0.72714 (14)	0.2053 (2)	0.0437 (5)
H7	0.2149	0.6548	0.2303	0.052*
C8	0.25277 (10)	0.79854 (16)	0.2901 (2)	0.0539 (5)
H8	0.2837	0.7739	0.3693	0.065*
C9	0.24803 (10)	0.90610 (16)	0.2577 (3)	0.0603 (6)
H9	0.2762	0.9542	0.3135	0.072*
C10	0.20180 (10)	0.94187 (16)	0.1432 (3)	0.0574 (6)
H10	0.1972	1.0148	0.1236	0.069*
C11	0.16178 (9)	0.86946 (14)	0.0560 (2)	0.0443 (5)
N1	0.0000	0.40677 (13)	−0.2500	0.0289 (4)
N2	0.08766 (7)	0.51551 (11)	−0.05920 (17)	0.0356 (4)
H2A	0.0775 (9)	0.5353 (13)	−0.161 (2)	0.043*
N3	0.12424 (6)	0.58391 (10)	0.04183 (16)	0.0341 (4)
N4	0.11444 (10)	0.91445 (15)	−0.0679 (3)	0.0687 (6)
O1	0.09010 (6)	0.37917 (9)	0.12168 (14)	0.0462 (4)
O2	0.11132 (16)	0.8667 (3)	−0.2020 (4)	0.0724 (9)	0.67
O3	0.0859 (5)	0.9956 (4)	−0.0349 (13)	0.111 (2)	0.67
O2'	0.0699 (4)	0.8669 (6)	−0.1308 (14)	0.155 (5)	0.33
O3'	0.1078 (10)	1.0114 (7)	−0.075 (2)	0.085 (3)	0.33

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0537 (16)	0.0193 (11)	0.0577 (17)	0.000	−0.0076 (13)	0.000
C2	0.0439 (10)	0.0277 (9)	0.0447 (11)	0.0031 (7)	−0.0084 (8)	0.0054 (7)
C3	0.0310 (8)	0.0264 (8)	0.0321 (9)	0.0016 (6)	−0.0010 (7)	−0.0004 (7)
C4	0.0320 (8)	0.0292 (9)	0.0335 (9)	0.0043 (7)	−0.0048 (7)	0.0002 (7)
C5	0.0399 (10)	0.0327 (9)	0.0365 (10)	−0.0019 (7)	−0.0040 (7)	0.0017 (8)
C6	0.0362 (9)	0.0336 (9)	0.0380 (10)	−0.0047 (7)	0.0040 (7)	−0.0021 (7)
C7	0.0446 (11)	0.0372 (10)	0.0484 (11)	−0.0054 (8)	−0.0063 (9)	−0.0011 (8)
C8	0.0481 (12)	0.0582 (13)	0.0542 (12)	−0.0094 (9)	−0.0098 (9)	−0.0053 (10)
C9	0.0607 (14)	0.0493 (13)	0.0702 (15)	−0.0181 (10)	−0.0029 (11)	−0.0179 (11)
C10	0.0632 (14)	0.0340 (11)	0.0753 (15)	−0.0092 (9)	0.0058 (11)	−0.0101 (10)
C11	0.0447 (11)	0.0347 (10)	0.0534 (12)	−0.0023 (8)	0.0020 (9)	−0.0003 (9)
N1	0.0325 (10)	0.0263 (10)	0.0275 (10)	0.000	−0.0030 (8)	0.000
N2	0.0452 (8)	0.0299 (8)	0.0305 (8)	−0.0053 (6)	−0.0099 (6)	0.0008 (6)
N3	0.0357 (8)	0.0311 (8)	0.0349 (8)	−0.0044 (6)	−0.0045 (6)	−0.0026 (6)
N4	0.0741 (14)	0.0415 (11)	0.0885 (16)	−0.0028 (10)	−0.0162 (11)	0.0182 (11)
O1	0.0642 (9)	0.0352 (7)	0.0373 (7)	0.0001 (6)	−0.0165 (6)	0.0056 (5)
O2	0.099 (2)	0.0500 (15)	0.0648 (17)	−0.0110 (16)	−0.0313 (16)	0.0134 (13)
O3	0.129 (6)	0.075 (3)	0.128 (6)	0.054 (3)	−0.006 (4)	0.016 (3)
O2'	0.125 (7)	0.076 (5)	0.253 (12)	−0.020 (6)	−0.119 (8)	0.033 (7)
O3'	0.114 (10)	0.048 (4)	0.095 (8)	0.022 (4)	0.004 (5)	0.018 (4)

Geometric parameters (Å, º)

C1—C2	1.3761 (19)	C7—H7	0.9300
C1—C2^i	1.3762 (19)	C8—C9	1.375 (3)
C1—H1	0.9300	C8—H8	0.9300
C2—C3	1.389 (2)	C9—C10	1.365 (3)
C2—H2	0.9300	C9—H9	0.9300
C3—N1	1.3340 (16)	C10—C11	1.386 (2)
C3—C4	1.506 (2)	C10—H10	0.9300
C4—O1	1.2152 (18)	C11—N4	1.471 (2)
C4—N2	1.347 (2)	N1—C3^i	1.3339 (16)
C5—N3	1.274 (2)	N2—N3	1.3799 (17)
C5—C6	1.473 (2)	N2—H2A	0.893 (17)
C5—H5	0.9300	N4—O2'	1.169 (6)
C6—C7	1.387 (2)	N4—O3	1.201 (5)
C6—C11	1.393 (2)	N4—O3'	1.222 (8)
C7—C8	1.379 (2)	N4—O2	1.262 (3)
C2—C1—C2^i	119.5 (2)	C7—C8—H8	120.0
C2—C1—H1	120.3	C10—C9—C8	119.65 (17)
C2^i—C1—H1	120.3	C10—C9—H9	120.2
C1—C2—C3	118.24 (15)	C8—C9—H9	120.2
C1—C2—H2	120.9	C9—C10—C11	119.92 (19)
C3—C2—H2	120.9	C9—C10—H10	120.0
N1—C3—C2	123.26 (15)	C11—C10—H10	120.0
N1—C3—C4	116.37 (14)	C10—C11—C6	122.01 (17)
C2—C3—C4	120.37 (13)	C10—C11—N4	116.47 (18)
O1—C4—N2	124.81 (14)	C6—C11—N4	121.52 (16)
O1—C4—C3	122.07 (14)	C3^i—N1—C3	117.45 (18)
N2—C4—C3	113.12 (13)	C4—N2—N3	120.11 (13)
N3—C5—C6	119.07 (15)	C4—N2—H2A	120.2 (11)
N3—C5—H5	120.5	N3—N2—H2A	119.4 (11)
C6—C5—H5	120.5	C5—N3—N2	113.78 (13)
C7—C6—C11	116.20 (15)	O2'—N4—O3	100.1 (8)
C7—C6—C5	120.09 (15)	O2'—N4—O3'	114.0 (12)
C11—C6—C5	123.70 (16)	O3—N4—O2	126.7 (6)
C8—C7—C6	122.09 (17)	O3'—N4—O2	115.3 (10)
C8—C7—H7	119.0	O2'—N4—C11	124.2 (5)
C6—C7—H7	119.0	O3—N4—C11	117.2 (6)
C9—C8—C7	120.07 (18)	O3'—N4—C11	118.5 (11)
C9—C8—H8	120.0	O2—N4—C11	115.9 (2)
C2^i—C1—C2—C3	−1.29 (11)	C5—C6—C11—C10	−178.17 (17)
C1—C2—C3—N1	2.8 (2)	C7—C6—C11—N4	−179.20 (18)
C1—C2—C3—C4	−178.15 (13)	C5—C6—C11—N4	2.0 (3)
N1—C3—C4—O1	158.06 (14)	C2—C3—N1—C3^i	−1.41 (12)
C2—C3—C4—O1	−21.1 (2)	C4—C3—N1—C3^i	179.46 (16)
N1—C3—C4—N2	−22.29 (19)	O1—C4—N2—N3	0.8 (2)
C2—C3—C4—N2	158.56 (15)	C3—C4—N2—N3	−178.83 (13)
N3—C5—C6—C7	12.8 (2)	C6—C5—N3—N2	−177.02 (14)
N3—C5—C6—C11	−168.41 (17)	C4—N2—N3—C5	−170.11 (15)
C11—C6—C7—C8	−2.1 (3)	C10—C11—N4—O2'	−166.0 (8)
C5—C6—C7—C8	176.74 (17)	C6—C11—N4—O2'	13.8 (9)
C6—C7—C8—C9	1.3 (3)	C10—C11—N4—O3	−40.0 (5)
C7—C8—C9—C10	1.1 (3)	C6—C11—N4—O3	139.8 (4)
C8—C9—C10—C11	−2.5 (3)	C10—C11—N4—O3'	−7.8 (8)
C9—C10—C11—C6	1.6 (3)	C6—C11—N4—O3'	172.0 (7)
C9—C10—C11—N4	−178.5 (2)	C10—C11—N4—O2	135.7 (3)
C7—C6—C11—C10	0.6 (3)	C6—C11—N4—O2	−44.4 (3)

Symmetry code: (i) −x, y, −z−1/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···O2	0.93	2.26	2.839 (3)	120
C5—H5···O1^ii	0.93	2.49	3.199 (2)	134
N2—H2A···O1^ii	0.893 (17)	2.125 (17)	2.9612 (19)	155.8 (15)
N2—H2A···N1	0.893 (17)	2.322 (17)	2.6690 (15)	103.0 (12)
C7—H7···N3	0.93	2.49	2.801 (2)	100

Symmetry code: (ii) x, −y+1, z−1/2.