1,2-Diisobutyrylhydrazine

The title mol­ecule, C₈H₁₆N₂O₂, possesses a crystallographically imposed center of symmetry. In the crystal structure, inter­molecular N—H...O hydrogen bonds link the mol­ecules into ribbons extended along the a axis.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.076
• wR factor = 0.236
• Data-to-parameter ratio = 16.0

checkCIF/PLATON results

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Alert level C
PLAT048_ALERT_1_C MoietyFormula Not Given ........................          ?
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       2.67 Ratio
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C2
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.27
PLAT340_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...          5

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

   2 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
   1 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

In this paper,we present a title compound, 1,2-Diisobutyrylhydrazine,(I), synthesized through the substituted reaction of iso-butyryl chloride with hydrazine hydrate under mild conditions.

In (I) (Fig. 1), the bond lengths and angles are normal and comparable to those observed in 1,2-dibenzoylhydrazine (Shanmuga Sundara Raj et al., 2000).

In the crystal, the molecules lies on inversion centers. There exist typical intermolecular N—H···O hydrogen bonds (Table 1), which link the molecules into ribbons extended along the a axis.

Related literature

For the crystal structure of 1,2-dibenzoylhydrazine, see: Shanmuga Sundara Raj et al. (2000).

S2. Experimental

A mixture of iso-butyryl chloride (2 mmol) and hydrazine hydrate (1.00 mmol) was well stirred at room temperature for 20 minutes. The crude compound was purified by recrystallization from ethanol. Elemental analysis: calculated for C₈H₁₆N₂O₂: C 55.79, H 9.36, N 16.27%; found: C 55.73, H 9.42, N 16.35%.

S3. Refinement

All H atoms were placed in idealized positions (C—H 0.96–0.98 Å, N—H 0.86 Å) and constrained to ride on their parent atoms, with U_iso(H) = 1.2–1.5 U_eq(parent atom).

Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SMART (Siemens, 1996); data reduction: 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) with atomic numbering and displacement ellipsoids drawn at the 30% probability level. The unlabelled atoms are related with the labelled ones by symmetry operation (1 - x, -y, 2 - z). Hydrogen atoms are omitted for clarity.
	Fig. 2. A portion of the crystal packing of (I) showing the ribbon of hydrogen-bonded (dashed lines) molecules.

1,2-Diisobutyrylhydrazine

Crystal data

C8H16N2O2	F(000) = 188
Mr = 172.23	Dx = 1.107 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
a = 4.7758 (8) Å	Cell parameters from 540 reflections
b = 10.9093 (13) Å	θ = 2.8–22.2°
c = 9.9204 (12) Å	µ = 0.08 mm^−1
β = 91.024 (1)°	T = 298 K
V = 516.78 (12) Å^3	Block, colourless
Z = 2	0.37 × 0.18 × 0.15 mm

Data collection

Bruker SMART CCD area-detector diffractometer	914 independent reflections
Radiation source: fine-focus sealed tube	557 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.065
phi and ω scans	θmax = 25.0°, θmin = 2.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −5→5
Tmin = 0.971, Tmax = 0.988	k = −12→12
2549 measured reflections	l = −11→8

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) = 0.236	H-atom parameters constrained
S = 0.99	w = 1/[σ^2(Fo^2) + (0.1473P)^2] where P = (Fo^2 + 2Fc^2)/3
914 reflections	(Δ/σ)max = 0.001
57 parameters	Δρmax = 0.31 e Å^−3
0 restraints	Δρmin = −0.24 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
N1	0.5501 (5)	0.0388 (2)	0.9509 (2)	0.0516 (8)
H1	0.7270	0.0428	0.9368	0.062*
O1	0.1184 (4)	0.10264 (19)	0.8985 (2)	0.0655 (9)
C1	0.3724 (6)	0.1075 (2)	0.8781 (3)	0.0465 (8)
C2	0.4985 (7)	0.1882 (3)	0.7727 (3)	0.0651 (11)
H2	0.7029	0.1858	0.7827	0.078*
C3	0.4004 (12)	0.3177 (4)	0.7895 (5)	0.1089 (17)
H3A	0.2018	0.3217	0.7733	0.163*
H3B	0.4938	0.3696	0.7264	0.163*
H3C	0.4428	0.3449	0.8796	0.163*
C4	0.4179 (13)	0.1435 (5)	0.6365 (4)	0.124 (2)
H4A	0.4935	0.0630	0.6233	0.186*
H4B	0.4904	0.1982	0.5699	0.186*
H4C	0.2174	0.1404	0.6281	0.186*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0353 (13)	0.0611 (17)	0.0587 (16)	0.0001 (11)	0.0101 (10)	0.0209 (12)
O1	0.0347 (12)	0.0771 (16)	0.0851 (18)	0.0045 (10)	0.0088 (10)	0.0328 (13)
C1	0.0349 (15)	0.0500 (16)	0.0547 (17)	0.0014 (12)	0.0048 (12)	0.0114 (14)
C2	0.050 (2)	0.075 (2)	0.071 (2)	0.0024 (16)	0.0088 (16)	0.0320 (19)
C3	0.138 (4)	0.075 (3)	0.115 (3)	−0.003 (3)	0.030 (3)	0.036 (3)
C4	0.172 (5)	0.121 (4)	0.080 (3)	−0.025 (4)	0.038 (3)	0.016 (3)

Geometric parameters (Å, º)

N1—C1	1.335 (3)	C2—H2	0.9800
N1—N1^i	1.382 (4)	C3—H3A	0.9600
N1—H1	0.8600	C3—H3B	0.9600
O1—C1	1.235 (3)	C3—H3C	0.9600
C1—C2	1.501 (4)	C4—H4A	0.9600
C2—C4	1.480 (5)	C4—H4B	0.9600
C2—C3	1.499 (5)	C4—H4C	0.9600
C1—N1—N1^i	120.0 (3)	C2—C3—H3A	109.5
C1—N1—H1	120.0	C2—C3—H3B	109.5
N1^i—N1—H1	120.0	H3A—C3—H3B	109.5
O1—C1—N1	120.3 (3)	C2—C3—H3C	109.5
O1—C1—C2	123.2 (2)	H3A—C3—H3C	109.5
N1—C1—C2	116.6 (3)	H3B—C3—H3C	109.5
C4—C2—C3	109.6 (4)	C2—C4—H4A	109.5
C4—C2—C1	110.0 (3)	C2—C4—H4B	109.5
C3—C2—C1	110.2 (3)	H4A—C4—H4B	109.5
C4—C2—H2	109.0	C2—C4—H4C	109.5
C3—C2—H2	109.0	H4A—C4—H4C	109.5
C1—C2—H2	109.0	H4B—C4—H4C	109.5

Symmetry code: (i) −x+1, −y, −z+2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1^ii	0.86	2.02	2.858 (3)	164

Symmetry code: (ii) x+1, y, z.