4-Iodo­benzohydrazide

In the structure of the title compound, C₇H₇IN₂O, the hydrazide group is inclined at 13.3 (3)° with respect to the benzene ring. The structure is stabilized by inter­molecular N—H...N and N—H...O hydrogen bonds involving the hydrazide group, resulting in six- and ten-membered rings with R₂²(6) and R₂²(10) graph-set notations, respectively.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.029
• wR factor = 0.106
• Data-to-parameter ratio = 19.0

checkCIF/PLATON results

No syntax errors found



Alert level C
            Value of measurement temperature given =   296.000
            Value of melting point given =     0.000
PLAT420_ALERT_2_C D-H Without Acceptor       N2     -   H2B    ...          ?
PLAT731_ALERT_1_C Bond    Calc     0.86(4), Rep   0.862(10) ......       4.00 su-Ra
              N2   -H2A     1.555   1.555
PLAT731_ALERT_1_C Bond    Calc     0.86(4), Rep   0.860(10) ......       4.00 su-Ra
              N2   -H2B     1.555   1.555
PLAT735_ALERT_1_C D-H     Calc     0.86(4), Rep   0.862(10) ......       4.00 su-Ra
              N2   -H2A     1.555   1.555
PLAT736_ALERT_1_C H...A   Calc     2.24(4), Rep   2.240(14) ......       2.86 su-Ra
              H2A  -O1      1.555   2.555

Alert level G
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          3

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

   4 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
   1 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

The title compound and its oxovanadium(IV) complex were investigated for their α-glucosidase inhibitory and urease activities. Free hydrazide ligand was found to be inactive, whereas its oxovanadium(IV) complex was found to be a potent inhibitor of α-glucosidase (Ashiq, Ara et al., 2008) and urease (Ara et al., 2007). Continuing our studies on the enzyme inhibition behavior of the title compound, (I), and to investigate the change in its activity due to complexation with vanadium center, we have synthesized (I) and report its crystal structure in this paper. The structures of benzhydrazide (Kallel et al., 1992), para-chloro (Saraogi et al., 2002) and para-bromo (Ashiq, Jamal et al., 2008) analogues of (I) have already been reported.

The molecule of the title compound (Fig. 1) is far from planar as is evident from the dihedral angle of 13.3 (3)° between the mean-planes of the phenyl ring (C1-C6) and the hydrazide moiety (N1/N2/O1/C7). The bond distances and bond angles in (I) are similar to the corersponding distances and angles reported in the structures quoted above. The molecules of (I) are involved in two types of hydrogen bonds involving hydrazide moiety. On one hand, the molecules lying about inversion centers form six membered rings via N1—H1A···N2ⁱ hydrogen bonding. On the other hand, the molecules related by c-glide form ten membered rings via N2—H2A···O1ⁱⁱ; detail of the hydrogen bonding have been presented in Table 1 and depicted in Fig. 2. The six and ten membered rings represent R₂²(6) and R₂²(10) graph set patterns, respectively (Bernstein et al., 1994).

Related literature

For related structures, see: Kallel et al. (1992); Saraogi et al. (2002); Ashiq, Jamal et al. (2008). For related literature, see: Ara et al. (2007); Ashiq, Ara et al. (2008); Bernstein et al. (1994).

S2. Experimental

All reagent-grade chemicals were obtained from Aldrich and Sigma Chemical companies and were used without further purification. To a solution of ethyl-4-iodobenzoate (5.5 g, 20 mmol) in 75 ml ethanol, hydrazine hydrate (5.0 ml, 100 mmol) was added. The mixture was refluxed for 5 h and a solid was obtained upon removal of the solvent by rotary evaporation. The resulting solid was washed with hexane to afford 4-iodobenzohydrazide (yield 84%).

S3. Refinement

H-atoms bonded to N-atoms were located from a difference map and were included in the refinement at those positions (using DFIX command with N—H = 0.86 (1) Å) while the aryl H-atoms were positioned geometrically in a riding mode, with C—H = 0.93 Å; for all H-atoms, U_iso = 1.2 times U_eq of the parent atoms.

Computing details

Data collection: APEX2 (Bruker, 2007); cell refinement: APEX2 (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures

	Fig. 1. ORTEP plot of the title compound with the ellipsoids drawn at the 50% probability level.
	Fig. 2. The hydrogen bonding patterns of (I) represented by dashed lines in the unit cell; H-atoms not involved in H-bonds have been excluded.

4-Iodobenzohydrazide

Crystal data

C7H7IN2O	F(000) = 992
Mr = 262.05	Dx = 2.072 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 3495 reflections
a = 28.4394 (18) Å	θ = 1.4–28.3°
b = 4.4514 (3) Å	µ = 3.76 mm^−1
c = 13.3216 (9) Å	T = 296 K
β = 94.292 (2)°	Needle, colorless
V = 1681.72 (19) Å^3	0.12 × 0.08 × 0.06 mm
Z = 8

Data collection

Bruker KappaAPEXII CCD diffractometer	2069 independent reflections
Radiation source: fine-focus sealed tube	1645 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.030
ω scans	θmax = 28.3°, θmin = 1.4°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −37→37
Tmin = 0.581, Tmax = 0.806	k = −5→5
9236 measured reflections	l = −17→17

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)] = 0.029	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.106	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ^2(Fo^2) + (0.0565P)^2 + 5.77P] where P = (Fo^2 + 2Fc^2)/3
2069 reflections	(Δ/σ)max = 0.001
109 parameters	Δρmax = 0.55 e Å^−3
3 restraints	Δρmin = −1.33 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.

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
I1	0.215538 (11)	1.09655 (7)	0.64904 (2)	0.05339 (15)
O1	0.05919 (14)	0.3811 (8)	0.2873 (2)	0.0582 (10)
N1	0.03174 (13)	0.1851 (9)	0.4262 (2)	0.0404 (8)
H1A	0.0321 (18)	0.170 (11)	0.4905 (9)	0.049*
N2	−0.00239 (14)	0.0017 (10)	0.3743 (2)	0.0408 (8)
H2A	−0.0195 (16)	0.119 (9)	0.335 (3)	0.049*
H2B	0.0127 (17)	−0.126 (9)	0.341 (3)	0.049*
C1	0.09627 (14)	0.5363 (10)	0.4445 (3)	0.0358 (8)
C2	0.09382 (15)	0.5693 (10)	0.5484 (3)	0.0403 (9)
H2	0.0695	0.4777	0.5799	0.048*
C3	0.12697 (15)	0.7356 (11)	0.6046 (3)	0.0441 (10)
H3	0.1244	0.7611	0.6733	0.053*
C4	0.16380 (15)	0.8638 (9)	0.5594 (3)	0.0397 (9)
C5	0.16696 (17)	0.8370 (11)	0.4566 (3)	0.0489 (11)
H5	0.1918	0.9256	0.4260	0.059*
C6	0.13267 (18)	0.6768 (12)	0.3998 (3)	0.0489 (11)
H6	0.1342	0.6637	0.3305	0.059*
C7	0.06129 (16)	0.3608 (9)	0.3801 (3)	0.0375 (9)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
I1	0.0461 (2)	0.0498 (2)	0.0626 (2)	−0.00097 (13)	−0.00736 (14)	0.00125 (13)
O1	0.069 (2)	0.080 (3)	0.0273 (13)	−0.0221 (19)	0.0124 (14)	−0.0003 (14)
N1	0.0469 (19)	0.0465 (19)	0.0277 (14)	−0.0046 (17)	0.0010 (13)	0.0067 (14)
N2	0.050 (2)	0.0425 (19)	0.0302 (15)	0.0003 (17)	0.0039 (14)	0.0051 (15)
C1	0.0384 (19)	0.038 (2)	0.0317 (17)	0.0053 (17)	0.0080 (14)	0.0015 (16)
C2	0.039 (2)	0.051 (3)	0.0317 (17)	−0.0001 (18)	0.0109 (15)	0.0041 (17)
C3	0.043 (2)	0.054 (3)	0.0352 (18)	0.001 (2)	0.0049 (16)	0.0000 (19)
C4	0.036 (2)	0.039 (2)	0.044 (2)	0.0035 (16)	−0.0004 (16)	0.0018 (17)
C5	0.048 (2)	0.053 (3)	0.047 (2)	−0.008 (2)	0.0168 (19)	0.002 (2)
C6	0.055 (3)	0.056 (3)	0.038 (2)	−0.004 (2)	0.0156 (19)	0.001 (2)
C7	0.042 (2)	0.041 (2)	0.0309 (17)	0.0060 (17)	0.0088 (15)	0.0037 (15)

Geometric parameters (Å, º)

I1—C4	2.098 (4)	C1—C7	1.486 (6)
O1—C7	1.237 (5)	C2—C3	1.375 (6)
N1—C7	1.332 (5)	C2—H2	0.9300
N1—N2	1.410 (6)	C3—C4	1.371 (6)
N1—H1A	0.857 (10)	C3—H3	0.9300
N2—H2A	0.862 (10)	C4—C5	1.384 (6)
N2—H2B	0.860 (10)	C5—C6	1.386 (7)
C1—C6	1.382 (6)	C5—H5	0.9300
C1—C2	1.398 (5)	C6—H6	0.9300
C7—N1—N2	123.3 (3)	C2—C3—H3	120.0
C7—N1—H1A	123 (3)	C3—C4—C5	120.5 (4)
N2—N1—H1A	114 (3)	C3—C4—I1	118.8 (3)
N1—N2—H2A	106 (3)	C5—C4—I1	120.7 (3)
N1—N2—H2B	107 (4)	C4—C5—C6	119.3 (4)
H2A—N2—H2B	112 (5)	C4—C5—H5	120.4
C6—C1—C2	118.3 (4)	C6—C5—H5	120.4
C6—C1—C7	118.6 (3)	C1—C6—C5	121.1 (4)
C2—C1—C7	123.1 (4)	C1—C6—H6	119.5
C3—C2—C1	120.8 (4)	C5—C6—H6	119.5
C3—C2—H2	119.6	O1—C7—N1	121.3 (4)
C1—C2—H2	119.6	O1—C7—C1	121.3 (4)
C4—C3—C2	120.0 (4)	N1—C7—C1	117.4 (3)
C4—C3—H3	120.0
C6—C1—C2—C3	−0.5 (7)	C7—C1—C6—C5	−178.3 (4)
C7—C1—C2—C3	−179.6 (4)	C4—C5—C6—C1	−1.9 (8)
C1—C2—C3—C4	−2.0 (7)	N2—N1—C7—O1	2.7 (7)
C2—C3—C4—C5	2.5 (7)	N2—N1—C7—C1	−178.5 (4)
C2—C3—C4—I1	−176.8 (3)	C6—C1—C7—O1	−12.8 (6)
C3—C4—C5—C6	−0.6 (7)	C2—C1—C7—O1	166.3 (4)
I1—C4—C5—C6	178.8 (4)	C6—C1—C7—N1	168.4 (4)
C2—C1—C6—C5	2.4 (7)	C2—C1—C7—N1	−12.4 (6)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···N2^i	0.86 (1)	2.19 (3)	2.964 (5)	151 (5)
N2—H2A···O1^ii	0.86 (1)	2.24 (1)	3.094 (5)	170 (5)
C3—H3···O1^iii	0.93	2.56	3.257 (5)	132

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