(E)-N′-(2-Hydroxy­benzyl­idene)-2-(4-isobutyl­phen­yl)propanohydrazide

The title hydrazide compound, C₂₀H₂₄N₂O₂, exists in a trans configuration with respect to the acyclic C=N bond and an intra­molecular O—H...N hydrogen bond generates an S(6) ring motif. The mean plane through the formohydrazide unit is essentially planar [maximum deviation = 0.025 (2) Å], and forms dihedral angles of 24.45 (16) and 87.14 (16)° with the two benzene rings. In the crystal structure, inter­molecular N—H...O and C—H...O hydrogen bonds link neighbouring mol­ecules into extended chains along the c axis, which incorporate R₂²(16) ring motifs. An inter­molecular C—H...π inter­action is also observed.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.076
• wR factor = 0.181
• Data-to-parameter ratio = 17.8

checkCIF/PLATON results

No syntax errors found



Alert level C
SHFSU01_ALERT_2_C  Test not performed. _refine_ls_shift/su_max and
            _refine_ls_shift/esd_max not present.
            Absolute value of the parameter shift to su ratio given   0.001
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       3.33 Ratio
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for        C14
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          1
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          5

Alert level G
PLAT960_ALERT_3_G Number of Intensities with I .LT. - 2*sig(I) ..           1
PLAT720_ALERT_4_G Number of Unusual/Non-Standard Labels ..........          2
PLAT793_ALERT_4_G The Model has Chirality at C9      (Verify) ....          R

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   5 ALERT level C = Check and explain
   3 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
   0 ALERT type 5 Informative message, check

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S1. Comment

Hydrazone compounds are obtained by the reaction of aromatic and heterocyclic hydrazides with mono- and di-aldehydes or ketones and they have revealed very versatile behaviour in metal coordination (Rodrìguez-Argüelles et al., 2004). Hydrazones have been demonstrated to possess a variety of pharmacological activities (Bedia et al., 2006; Rollas et al., 2002; Terzioglu & Gürsoy, 2003). These observations have been the guidelines for the development of new hydrazone incorporating ibuprofen. Prompted by these observations and in continuation of our work (Fun et al., 2009b), we herein report the structure of this new hydrazone.

The title hydrazide compound (Fig. 1) exists in a trans configuration with respect to the acyclic C7═N1 bond. An intramolecular O1—H1O1···N1 hydrogen bond (Table 1) generates a six-membered ring, producing an S(6) ring motif (Bernstein et al., 1995). The mean plane through the formohydrazide unit (N1/N2/C8/O2) is essentially planar, with maximum deviation of 0.025 (2) Å for atom C8. This plane is inclined to the C1-C6 benzene ring at a dihedral angle of 24.45 (16)°, and almost perpendicular to the C10-C15 benzene ring, as indicated by the dihedral angle of 87.14 (16)°. The bond lengths and angles are within normal ranges and comparable to those closely related structures (Fun et al., 2009a,b).

In the crystal packing (Fig. 2), intermolecular N2—H1N2···O2 and C14—H14A···O1 hydrogen bonds (Table 1) link neighbouring molecules into one-dimensional infinite chains of R²₂(16) hydrogen bond ring motifs (Bernstein et al., 1995) along the c axis. An intermolecular C—H···π interaction (Table 1) involving the C10-C15 benzene ring is also observed.

Related literature

For the metal coordination and pharmacological activity of the title compound, see: Bedia et al. (2006); Rodrìguez-Argüelles et al. (2004); Rollas et al. (2002); Terzioglu & Gürsoy (2003). For hydrogen-bond motifs, see: Bernstein et al. (1995). For related structures, see: Fun et al. (2009a,b). For bond-length data, see: Allen et al. (1987). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986). Cg1 is the centroid of the C10–C15 benzene ring.

S2. Experimental

The title compound was obtained by refluxing for 1 h salicylaldehyde (0.01 mol), 2-(4-isobutylphenyl)propanehydrazide (0.01 mol) and ethanol (30 ml) with the addition of three drops of concentrated sulphuric acid. The solid product obtained was filtered, washed with ethanol and dried. Colourless blocks of (I) were obtained by slow evaporation from ethanol. Yield was 74 %. M.p. 426 K.

S3. Refinement

The H atoms bound to atoms O1 and N2 were located from the difference Fourier map and allowed to refine freely. All the other H atoms were placed in calculated positions, with C—H = 0.93 – 0.97 Å, and as riding, with U_iso = 1.2 or 1.5 U_eq(C). A rotating group model was used for the methyl groups. The reflection (020) was omitted from the refinement as the intensity was affected by the beam backstop.

Computing details

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures

	Fig. 1. The molecular structure of (I), showing 50% probability displacement ellipsoids for non-H atoms. The intramolecular hydrogen bond is shown as a dashed line.
	Fig. 2. The crystal structure of (I), viewed along the a axis, showing one-dimensional extended chains of R^22(16) ring motif along the c axis. Intermolecular hydrogen bonds are shown as dashed lines.

(E)-N'-(2-Hydroxybenzylidene)-2-(4-isobutylphenyl)propanohydrazide

Crystal data

C20H24N2O2	F(000) = 696
Mr = 324.41	Dx = 1.220 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 7778 reflections
a = 5.5017 (2) Å	θ = 2.4–30.0°
b = 33.0204 (14) Å	µ = 0.08 mm^−1
c = 9.7279 (4) Å	T = 100 K
β = 91.731 (3)°	Block, colourless
V = 1766.45 (12) Å^3	0.39 × 0.24 × 0.19 mm
Z = 4

Data collection

Bruker SMART APEXII CCD diffractometer	4059 independent reflections
Radiation source: fine-focus sealed tube	3190 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.042
ϕ and ω scans	θmax = 27.5°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −7→7
Tmin = 0.970, Tmax = 0.985	k = −38→42
18817 measured reflections	l = −12→12

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)] = 0.076	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.181	H atoms treated by a mixture of independent and constrained refinement
S = 1.18	w = 1/[σ^2(Fo^2) + (0.0443P)^2 + 2.5698P] where P = (Fo^2 + 2Fc^2)/3
4059 reflections	(Δ/σ)max < 0.001
228 parameters	Δρmax = 0.26 e Å^−3
0 restraints	Δρmin = −0.28 e Å^−3

Special details

Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1)K.

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.

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 > 2sigma(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
O1	−0.2604 (4)	0.18426 (6)	0.5584 (2)	0.0358 (5)
O2	0.3223 (3)	0.25847 (5)	0.60286 (15)	0.0209 (4)
N1	0.1237 (4)	0.20555 (6)	0.4218 (2)	0.0199 (5)
N2	0.3012 (4)	0.23282 (6)	0.3875 (2)	0.0210 (5)
C1	−0.1353 (6)	0.11240 (9)	0.2812 (3)	0.0364 (7)
H1A	−0.0286	0.1087	0.2099	0.044*
C2	−0.3138 (6)	0.08401 (9)	0.3013 (3)	0.0367 (8)
H2A	−0.3268	0.0614	0.2448	0.044*
C3	−0.4735 (6)	0.08962 (9)	0.4065 (4)	0.0385 (8)
H3A	−0.5952	0.0706	0.4205	0.046*
C4	−0.4540 (5)	0.12339 (9)	0.4918 (4)	0.0382 (7)
H4A	−0.5625	0.1268	0.5624	0.046*
C5	−0.2736 (5)	0.15194 (8)	0.4721 (3)	0.0285 (6)
C6	−0.1095 (5)	0.14680 (8)	0.3650 (3)	0.0269 (6)
C7	0.0819 (5)	0.17603 (8)	0.3390 (3)	0.0276 (6)
H7A	0.1748	0.1732	0.2613	0.033*
C8	0.3850 (4)	0.25968 (7)	0.4827 (2)	0.0156 (5)
C9	0.5550 (5)	0.29208 (8)	0.4303 (3)	0.0235 (5)
H9A	0.6170	0.2834	0.3417	0.028*
C10	0.4016 (5)	0.33029 (8)	0.4081 (3)	0.0235 (5)
C11	0.4132 (5)	0.36299 (8)	0.4983 (3)	0.0310 (6)
H11A	0.5260	0.3628	0.5715	0.037*
C12	0.2587 (5)	0.39598 (8)	0.4807 (3)	0.0277 (6)
H12A	0.2735	0.4177	0.5411	0.033*
C13	0.0842 (6)	0.39741 (8)	0.3763 (3)	0.0277 (6)
C14	0.0756 (8)	0.36506 (9)	0.2855 (3)	0.0518 (11)
H14A	−0.0389	0.3652	0.2131	0.062*
C15	0.2335 (7)	0.33241 (9)	0.2998 (3)	0.0438 (9)
H15A	0.2259	0.3116	0.2354	0.053*
C16	−0.0929 (6)	0.43214 (8)	0.3616 (3)	0.0319 (7)
H16A	−0.1484	0.4392	0.4522	0.038*
H16B	−0.2334	0.4230	0.3075	0.038*
C17	0.0063 (6)	0.47049 (8)	0.2944 (3)	0.0331 (7)
H17A	0.1393	0.4809	0.3537	0.040*
C18	−0.1918 (7)	0.50278 (9)	0.2851 (3)	0.0435 (8)
H18A	−0.1264	0.5272	0.2472	0.065*
H18B	−0.2499	0.5082	0.3754	0.065*
H18C	−0.3239	0.4933	0.2270	0.065*
C19	0.1076 (7)	0.46188 (9)	0.1530 (3)	0.0402 (8)
H19A	0.1558	0.4869	0.1114	0.060*
H19B	−0.0152	0.4491	0.0960	0.060*
H19C	0.2460	0.4443	0.1628	0.060*
C20	0.7674 (5)	0.29712 (9)	0.5318 (4)	0.0423 (8)
H20A	0.8636	0.2729	0.5335	0.063*
H20B	0.7074	0.3022	0.6218	0.063*
H20C	0.8658	0.3195	0.5043	0.063*
H1N2	0.346 (6)	0.2342 (9)	0.303 (3)	0.034 (9)*
H1O1	−0.127 (8)	0.1984 (12)	0.539 (4)	0.064 (13)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0260 (11)	0.0248 (10)	0.0569 (14)	−0.0014 (8)	0.0068 (10)	−0.0075 (9)
O2	0.0300 (10)	0.0253 (9)	0.0074 (7)	0.0012 (7)	0.0012 (7)	−0.0001 (7)
N1	0.0248 (11)	0.0194 (10)	0.0150 (9)	−0.0027 (8)	−0.0055 (8)	0.0027 (8)
N2	0.0329 (12)	0.0221 (11)	0.0083 (9)	−0.0060 (9)	0.0021 (8)	0.0006 (8)
C1	0.060 (2)	0.0304 (15)	0.0184 (13)	−0.0137 (14)	−0.0084 (13)	0.0022 (11)
C2	0.057 (2)	0.0258 (15)	0.0268 (14)	−0.0115 (13)	−0.0136 (14)	0.0030 (12)
C3	0.0319 (16)	0.0256 (15)	0.057 (2)	−0.0059 (12)	−0.0153 (15)	0.0061 (14)
C4	0.0206 (14)	0.0292 (15)	0.065 (2)	0.0004 (11)	−0.0005 (14)	−0.0014 (14)
C5	0.0243 (13)	0.0198 (13)	0.0409 (16)	0.0032 (10)	−0.0087 (12)	0.0015 (11)
C6	0.0379 (15)	0.0226 (13)	0.0192 (12)	−0.0055 (11)	−0.0128 (11)	0.0059 (10)
C7	0.0434 (16)	0.0256 (14)	0.0134 (11)	−0.0049 (12)	−0.0048 (11)	0.0025 (10)
C8	0.0146 (11)	0.0190 (11)	0.0132 (10)	0.0031 (9)	−0.0001 (8)	0.0004 (9)
C9	0.0239 (13)	0.0202 (12)	0.0272 (13)	−0.0009 (10)	0.0118 (10)	−0.0033 (10)
C10	0.0311 (14)	0.0191 (12)	0.0212 (12)	−0.0024 (10)	0.0130 (10)	0.0016 (10)
C11	0.0232 (14)	0.0261 (14)	0.0435 (16)	−0.0025 (11)	−0.0013 (12)	−0.0117 (12)
C12	0.0255 (14)	0.0239 (13)	0.0339 (15)	−0.0010 (11)	0.0057 (11)	−0.0101 (11)
C13	0.0454 (17)	0.0201 (13)	0.0181 (12)	0.0021 (11)	0.0076 (11)	0.0042 (10)
C14	0.105 (3)	0.0295 (16)	0.0196 (14)	0.0204 (18)	−0.0219 (17)	−0.0017 (12)
C15	0.095 (3)	0.0228 (14)	0.0131 (12)	0.0159 (16)	−0.0038 (15)	−0.0027 (11)
C16	0.0447 (18)	0.0244 (14)	0.0265 (14)	0.0061 (12)	0.0002 (12)	0.0016 (11)
C17	0.0498 (19)	0.0229 (14)	0.0262 (14)	0.0030 (12)	−0.0069 (13)	0.0019 (11)
C18	0.062 (2)	0.0271 (15)	0.0413 (18)	0.0081 (15)	−0.0068 (16)	0.0036 (13)
C19	0.057 (2)	0.0328 (16)	0.0305 (16)	0.0008 (14)	−0.0011 (14)	0.0074 (13)
C20	0.0220 (14)	0.0266 (15)	0.078 (2)	−0.0012 (11)	−0.0006 (15)	−0.0134 (15)

Geometric parameters (Å, º)

O1—C5	1.359 (3)	C11—C12	1.389 (4)
O1—H1O1	0.89 (4)	C11—H11A	0.9300
O2—C8	1.229 (3)	C12—C13	1.377 (4)
N1—C7	1.281 (3)	C12—H12A	0.9300
N1—N2	1.377 (3)	C13—C14	1.386 (4)
N2—C8	1.354 (3)	C13—C16	1.509 (4)
N2—H1N2	0.86 (3)	C14—C15	1.389 (4)
C1—C2	1.376 (4)	C14—H14A	0.9300
C1—C6	1.403 (4)	C15—H15A	0.9300
C1—H1A	0.9300	C16—C17	1.533 (4)
C2—C3	1.382 (5)	C16—H16A	0.9700
C2—H2A	0.9300	C16—H16B	0.9700
C3—C4	1.392 (4)	C17—C18	1.526 (4)
C3—H3A	0.9300	C17—C19	1.526 (4)
C4—C5	1.387 (4)	C17—H17A	0.9800
C4—H4A	0.9300	C18—H18A	0.9600
C5—C6	1.409 (4)	C18—H18B	0.9600
C6—C7	1.456 (4)	C18—H18C	0.9600
C7—H7A	0.9300	C19—H19A	0.9600
C8—C9	1.519 (3)	C19—H19B	0.9600
C9—C20	1.516 (4)	C19—H19C	0.9600
C9—C10	1.530 (4)	C20—H20A	0.9600
C9—H9A	0.9800	C20—H20B	0.9600
C10—C15	1.382 (4)	C20—H20C	0.9600
C10—C11	1.392 (4)
C5—O1—H1O1	108 (3)	C13—C12—H12A	119.1
C7—N1—N2	117.4 (2)	C11—C12—H12A	119.1
C8—N2—N1	119.4 (2)	C12—C13—C14	117.0 (3)
C8—N2—H1N2	121 (2)	C12—C13—C16	122.0 (2)
N1—N2—H1N2	119 (2)	C14—C13—C16	121.0 (3)
C2—C1—C6	122.0 (3)	C13—C14—C15	121.6 (3)
C2—C1—H1A	119.0	C13—C14—H14A	119.2
C6—C1—H1A	119.0	C15—C14—H14A	119.2
C1—C2—C3	119.1 (3)	C10—C15—C14	121.2 (3)
C1—C2—H2A	120.4	C10—C15—H15A	119.4
C3—C2—H2A	120.4	C14—C15—H15A	119.4
C2—C3—C4	120.6 (3)	C13—C16—C17	115.5 (3)
C2—C3—H3A	119.7	C13—C16—H16A	108.4
C4—C3—H3A	119.7	C17—C16—H16A	108.4
C5—C4—C3	120.3 (3)	C13—C16—H16B	108.4
C5—C4—H4A	119.8	C17—C16—H16B	108.4
C3—C4—H4A	119.8	H16A—C16—H16B	107.5
O1—C5—C4	118.3 (3)	C18—C17—C19	110.9 (2)
O1—C5—C6	121.9 (2)	C18—C17—C16	109.8 (3)
C4—C5—C6	119.8 (3)	C19—C17—C16	112.0 (2)
C1—C6—C5	118.1 (3)	C18—C17—H17A	108.0
C1—C6—C7	119.8 (3)	C19—C17—H17A	108.0
C5—C6—C7	122.1 (2)	C16—C17—H17A	108.0
N1—C7—C6	120.8 (3)	C17—C18—H18A	109.5
N1—C7—H7A	119.6	C17—C18—H18B	109.5
C6—C7—H7A	119.6	H18A—C18—H18B	109.5
O2—C8—N2	122.0 (2)	C17—C18—H18C	109.5
O2—C8—C9	122.4 (2)	H18A—C18—H18C	109.5
N2—C8—C9	115.6 (2)	H18B—C18—H18C	109.5
C20—C9—C8	109.2 (2)	C17—C19—H19A	109.5
C20—C9—C10	114.4 (2)	C17—C19—H19B	109.5
C8—C9—C10	106.6 (2)	H19A—C19—H19B	109.5
C20—C9—H9A	108.8	C17—C19—H19C	109.5
C8—C9—H9A	108.8	H19A—C19—H19C	109.5
C10—C9—H9A	108.8	H19B—C19—H19C	109.5
C15—C10—C11	117.3 (3)	C9—C20—H20A	109.5
C15—C10—C9	120.2 (2)	C9—C20—H20B	109.5
C11—C10—C9	122.4 (2)	H20A—C20—H20B	109.5
C12—C11—C10	120.9 (3)	C9—C20—H20C	109.5
C12—C11—H11A	119.5	H20A—C20—H20C	109.5
C10—C11—H11A	119.5	H20B—C20—H20C	109.5
C13—C12—C11	121.9 (3)
C7—N1—N2—C8	−167.2 (2)	N2—C8—C9—C10	99.7 (2)
C6—C1—C2—C3	0.4 (4)	C20—C9—C10—C15	167.3 (3)
C1—C2—C3—C4	−0.3 (4)	C8—C9—C10—C15	−71.9 (3)
C2—C3—C4—C5	0.0 (4)	C20—C9—C10—C11	−16.6 (4)
C3—C4—C5—O1	−179.5 (3)	C8—C9—C10—C11	104.2 (3)
C3—C4—C5—C6	0.1 (4)	C15—C10—C11—C12	1.0 (4)
C2—C1—C6—C5	−0.2 (4)	C9—C10—C11—C12	−175.2 (3)
C2—C1—C6—C7	−179.7 (3)	C10—C11—C12—C13	1.7 (4)
O1—C5—C6—C1	179.6 (2)	C11—C12—C13—C14	−2.5 (5)
C4—C5—C6—C1	0.0 (4)	C11—C12—C13—C16	176.6 (3)
O1—C5—C6—C7	−0.9 (4)	C12—C13—C14—C15	0.7 (5)
C4—C5—C6—C7	179.4 (3)	C16—C13—C14—C15	−178.4 (3)
N2—N1—C7—C6	−177.5 (2)	C11—C10—C15—C14	−2.8 (5)
C1—C6—C7—N1	−173.3 (2)	C9—C10—C15—C14	173.5 (3)
C5—C6—C7—N1	7.3 (4)	C13—C14—C15—C10	2.0 (6)
N1—N2—C8—O2	6.1 (3)	C12—C13—C16—C17	79.8 (3)
N1—N2—C8—C9	−172.1 (2)	C14—C13—C16—C17	−101.1 (3)
O2—C8—C9—C20	45.5 (3)	C13—C16—C17—C18	179.5 (2)
N2—C8—C9—C20	−136.3 (2)	C13—C16—C17—C19	55.8 (3)
O2—C8—C9—C10	−78.5 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H1N2···O2^i	0.87 (3)	1.96 (3)	2.790 (2)	159 (3)
O1—H1O1···N1	0.90 (4)	1.83 (4)	2.626 (3)	147 (4)
C14—H14A···O1^i	0.93	2.51	3.272 (4)	139
C20—H20C···Cg1^ii	0.96	2.80	3.722 (3)	161

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