N²,N^2′-Bis(2-hydr­oxy-3-methoxy­benzyl­idene)terephthalohydrazide dihydrate

The organic molecule of the title compound, C₂₄H₂₂N₄O₆·2H₂O, is centrosymmetric. The dihedral angle between the two benzene rings is 3.25 (7)°. The structure is stabilized by intra­molecular O—H...O, and inter­molecular N—H...O and O—H...O hydrogen bonds, forming an intricate three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• R factor = 0.055
• wR factor = 0.133
• Data-to-parameter ratio = 12.6

checkCIF/PLATON results

No syntax errors found


No errors found in this datablock

---

S1. Comment

Recently, we have reported some organotin(IV) complexes with Schiff base of o-vanillin-2-thiophenoylhydrazone (Yin & Chen, 2006). As an extension of our work on the structural characterization of Schiff base compounds, the title compound, (I), is reported here (Fig. 1).

In Fig. 1, it can be viewed as a centrosymmetric configuration, where one half of the molecule comprises the crystallographic asymmetric unit and the other half is generated by an inversion centre. In the compound, the N2═C5 bond length of 1.283 (4) Å (Table 1) conforms to the value for a double bond, while the N1—C1 bond [1.360 (4) Å] and N1—N2 bond [1.376 (3) Å] are intermediate between a double bond and a single bond because of conjugation effects in the molecule. The two benzene rings make a dihedral angle of 3.2 °.

The occurrence O—H···O and N—H···–O hydrogen bonds (Table 2) results in the formation of an intricated three dimensionnal network (Fig. 2).

Related literature

For the structures of some organotin(IV) complexes with the Schiff base o-vanillin-2-thiophenoylhydrazone, see Yin & Chen (2006). The Schiff base ligand chelates in a tridentate manner with O, N and O atoms.

S2. Experimental

Compound (I) was synthesized by the reaction of terephthalohydrazide (5 mmol) with 2-hydroxy-3-methoxybenzaldehyde (10 mmol). Single crystals of (I) suitable for X-ray diffraction were obtained by slow evaporation of an ethanol solution.

S3. Refinement

All H atoms attached to C atoms and N atom were fixed geometrically and treated as riding with C—H = 0.93 Å (aromatic), C—H = 0.96 Å (methylaromatic) and N—H = 0.86 Å with U_iso(H) = 1.2 or 1.5U_eq (C or N). H atoms of water molecule were located in difference Fourier maps and included in the subsequent refinement using restraints [O—H = 0.85 (1) Å and H···H = 1.39 (2) Å] with U_iso(H) = 1.5U_eq(O).

Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SMART or SAINT? (Siemens, 1996); data reduction: SMART or SAINT? (Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: SHELXTL (Sheldrick, 1997b); software used to prepare material for publication: SHELXTL (Sheldrick, 1997b).

Figures

	Fig. 1. The molecular structure of (I), showing 30% probability displacement ellipsoids and the atom-numbering scheme·The intramolecular hydrogen bonds are shown as dashed lines. [Symmetry code: (A) -x, -y + 1, -z - 1]
	Fig. 2. The crystal packing of the title compound.

N²,N^2'-Bis(2-hydroxy-3- methoxybenzylidene)terephthalohydrazide dihydrate

Crystal data

C24H22N4O6·2H2O	F(000) = 524
Mr = 498.49	Dx = 1.398 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 1112 reflections
a = 7.2854 (12) Å	θ = 2.9–27.6°
b = 25.711 (2) Å	µ = 0.11 mm^−1
c = 6.4780 (11) Å	T = 298 K
β = 102.613 (2)°	Block, colourless
V = 1184.1 (3) Å^3	0.28 × 0.17 × 0.14 mm
Z = 2

Data collection

Siemens SMART CCD area-detector diffractometer	2052 independent reflections
Radiation source: fine-focus sealed tube	1003 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.067
ϕ and ω scans	θmax = 25.0°, θmin = 1.6°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −8→8
Tmin = 0.971, Tmax = 0.985	k = −30→28
5724 measured reflections	l = −7→7

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)] = 0.055	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.133	H-atom parameters constrained
S = 1.00	w = 1/[σ^2(Fo^2) + (0.0526P)^2] where P = (Fo^2 + 2Fc^2)/3
2052 reflections	(Δ/σ)max < 0.001
163 parameters	Δρmax = 0.21 e Å^−3
0 restraints	Δρmin = −0.23 e Å^−3

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

	x	y	z	Uiso*/Ueq
N1	−0.0134 (4)	0.57438 (9)	−0.0098 (4)	0.0298 (7)
H1	−0.1305	0.5725	−0.0711	0.036*
N2	0.0440 (4)	0.60098 (9)	0.1775 (4)	0.0299 (7)
O1	0.2850 (3)	0.55158 (9)	−0.0035 (4)	0.0475 (7)
O2	0.3017 (3)	0.63702 (8)	0.4869 (4)	0.0415 (7)
H2	0.2621	0.6214	0.3757	0.062*
O3	0.3871 (3)	0.68755 (8)	0.8377 (4)	0.0427 (7)
O4	0.5917 (3)	0.58503 (9)	0.8496 (4)	0.0513 (7)
H13	0.5422	0.6126	0.7893	0.077*
H14	0.5073	0.5706	0.9022	0.077*
C1	0.1207 (5)	0.55120 (12)	−0.0950 (5)	0.0306 (9)
C2	0.0522 (5)	0.52507 (11)	−0.3037 (5)	0.0286 (8)
C3	0.1867 (5)	0.50515 (12)	−0.4035 (6)	0.0367 (9)
H3	0.3134	0.5085	−0.3394	0.044*
C4	0.1356 (5)	0.48038 (12)	−0.5968 (5)	0.0343 (9)
H4	0.2283	0.4672	−0.6610	0.041*
C5	−0.0843 (5)	0.62087 (12)	0.2609 (5)	0.0354 (9)
H5	−0.2104	0.6168	0.1955	0.042*
C6	−0.0321 (5)	0.64951 (12)	0.4562 (5)	0.0282 (8)
C7	0.1552 (5)	0.65613 (11)	0.5602 (5)	0.0284 (8)
C8	0.1981 (5)	0.68380 (11)	0.7509 (5)	0.0302 (8)
C9	0.0568 (5)	0.70477 (12)	0.8354 (6)	0.0378 (9)
H9	0.0861	0.7234	0.9614	0.045*
C10	−0.1276 (5)	0.69803 (13)	0.7330 (6)	0.0402 (9)
H10	−0.2226	0.7122	0.7908	0.048*
C11	−0.1739 (5)	0.67075 (12)	0.5469 (6)	0.0369 (9)
H11	−0.2996	0.6663	0.4804	0.044*
C12	0.4402 (6)	0.71070 (15)	1.0399 (6)	0.0602 (12)
H12A	0.3977	0.7461	1.0325	0.090*
H12B	0.5747	0.7098	1.0860	0.090*
H12C	0.3844	0.6918	1.1385	0.090*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0271 (16)	0.0405 (17)	0.0199 (17)	−0.0041 (13)	0.0008 (13)	−0.0077 (14)
N2	0.0338 (18)	0.0308 (16)	0.0243 (18)	−0.0018 (13)	0.0046 (15)	−0.0073 (13)
O1	0.0263 (16)	0.0760 (19)	0.0380 (17)	−0.0021 (13)	0.0022 (14)	−0.0161 (14)
O2	0.0286 (15)	0.0549 (15)	0.0391 (16)	0.0065 (12)	0.0029 (13)	−0.0126 (12)
O3	0.0401 (16)	0.0468 (15)	0.0379 (16)	−0.0051 (12)	0.0013 (13)	−0.0162 (13)
O4	0.0289 (15)	0.0623 (16)	0.0606 (19)	0.0045 (12)	0.0054 (14)	0.0005 (15)
C1	0.036 (2)	0.032 (2)	0.025 (2)	−0.0032 (17)	0.0081 (19)	−0.0007 (17)
C2	0.031 (2)	0.0276 (18)	0.027 (2)	−0.0023 (15)	0.0053 (18)	−0.0008 (15)
C3	0.026 (2)	0.048 (2)	0.036 (2)	−0.0066 (17)	0.0047 (18)	−0.0127 (19)
C4	0.032 (2)	0.042 (2)	0.030 (2)	−0.0017 (16)	0.0083 (19)	−0.0098 (18)
C5	0.032 (2)	0.040 (2)	0.033 (2)	0.0029 (17)	0.0032 (18)	−0.0064 (18)
C6	0.030 (2)	0.0297 (19)	0.024 (2)	0.0040 (15)	0.0028 (18)	−0.0010 (16)
C7	0.035 (2)	0.0237 (18)	0.027 (2)	−0.0002 (16)	0.0092 (19)	0.0016 (16)
C8	0.033 (2)	0.0237 (18)	0.031 (2)	−0.0014 (16)	0.0009 (18)	0.0011 (16)
C9	0.047 (3)	0.039 (2)	0.027 (2)	−0.0007 (18)	0.006 (2)	−0.0081 (17)
C10	0.046 (3)	0.047 (2)	0.030 (2)	0.0123 (18)	0.013 (2)	−0.0019 (19)
C11	0.031 (2)	0.043 (2)	0.038 (2)	0.0076 (17)	0.0081 (19)	−0.0022 (18)
C12	0.059 (3)	0.083 (3)	0.032 (3)	−0.012 (2)	−0.004 (2)	−0.022 (2)

Geometric parameters (Å, º)

N1—C1	1.360 (4)	C4—C2^i	1.387 (4)
N1—N2	1.376 (3)	C4—H4	0.9300
N1—H1	0.8600	C5—C6	1.441 (4)
N2—C5	1.283 (4)	C5—H5	0.9300
O1—C1	1.214 (4)	C6—C7	1.394 (4)
O2—C7	1.352 (3)	C6—C11	1.406 (4)
O2—H2	0.8200	C7—C8	1.400 (4)
O3—C8	1.372 (4)	C8—C9	1.377 (4)
O3—C12	1.414 (4)	C9—C10	1.373 (5)
O4—H13	0.8500	C9—H9	0.9300
O4—H14	0.8500	C10—C11	1.372 (5)
C1—C2	1.495 (5)	C10—H10	0.9300
C2—C3	1.384 (4)	C11—H11	0.9300
C2—C4^i	1.387 (4)	C12—H12A	0.9600
C3—C4	1.381 (4)	C12—H12B	0.9600
C3—H3	0.9300	C12—H12C	0.9600
C1—N1—N2	118.0 (3)	C7—C6—C5	122.0 (3)
C1—N1—H1	121.0	C11—C6—C5	119.2 (3)
N2—N1—H1	121.0	O2—C7—C6	123.4 (3)
C5—N2—N1	117.4 (3)	O2—C7—C8	117.0 (3)
C7—O2—H2	109.5	C6—C7—C8	119.7 (3)
C8—O3—C12	117.2 (3)	O3—C8—C9	125.4 (3)
H13—O4—H14	106.0	O3—C8—C7	114.1 (3)
O1—C1—N1	121.2 (3)	C9—C8—C7	120.5 (3)
O1—C1—C2	122.9 (3)	C10—C9—C8	119.7 (3)
N1—C1—C2	115.9 (3)	C10—C9—H9	120.1
C3—C2—C4^i	118.2 (3)	C8—C9—H9	120.1
C3—C2—C1	117.3 (3)	C11—C10—C9	121.1 (3)
C4^i—C2—C1	124.5 (3)	C11—C10—H10	119.5
C4—C3—C2	121.1 (3)	C9—C10—H10	119.5
C4—C3—H3	119.5	C10—C11—C6	120.3 (3)
C2—C3—H3	119.5	C10—C11—H11	119.9
C3—C4—C2^i	120.7 (3)	C6—C11—H11	119.9
C3—C4—H4	119.6	O3—C12—H12A	109.5
C2^i—C4—H4	119.6	O3—C12—H12B	109.5
N2—C5—C6	119.8 (3)	H12A—C12—H12B	109.5
N2—C5—H5	120.1	O3—C12—H12C	109.5
C6—C5—H5	120.1	H12A—C12—H12C	109.5
C7—C6—C11	118.8 (3)	H12B—C12—H12C	109.5
C1—N1—N2—C5	−177.2 (3)	C11—C6—C7—C8	−0.3 (4)
N2—N1—C1—O1	3.8 (4)	C5—C6—C7—C8	−179.3 (3)
N2—N1—C1—C2	−177.0 (2)	C12—O3—C8—C9	6.1 (5)
O1—C1—C2—C3	−6.5 (5)	C12—O3—C8—C7	−174.2 (3)
N1—C1—C2—C3	174.4 (3)	O2—C7—C8—O3	−0.1 (4)
O1—C1—C2—C4^i	173.6 (3)	C6—C7—C8—O3	179.9 (3)
N1—C1—C2—C4^i	−5.5 (4)	O2—C7—C8—C9	179.6 (3)
C4^i—C2—C3—C4	−0.1 (5)	C6—C7—C8—C9	−0.4 (5)
C1—C2—C3—C4	180.0 (3)	O3—C8—C9—C10	−179.7 (3)
C2—C3—C4—C2^i	0.1 (5)	C7—C8—C9—C10	0.7 (5)
N1—N2—C5—C6	−179.5 (3)	C8—C9—C10—C11	−0.1 (5)
N2—C5—C6—C7	−0.5 (5)	C9—C10—C11—C6	−0.6 (5)
N2—C5—C6—C11	−179.5 (3)	C7—C6—C11—C10	0.8 (5)
C11—C6—C7—O2	179.7 (3)	C5—C6—C11—C10	179.8 (3)
C5—C6—C7—O2	0.7 (5)

Symmetry code: (i) −x, −y+1, −z−1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O4^ii	0.86	2.00	2.835 (3)	163
O4—H14···O1^iii	0.85	1.92	2.751 (3)	167
O2—H2···N2	0.82	1.89	2.599 (4)	145
O4—H13···O3	0.85	2.29	3.021 (3)	144
O4—H13···O2	0.85	2.41	3.099 (3)	139

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