Hydro­gen-bonded R22(8) dimers in (E)-{[2-(phenyl­diazenyl)­phenyl]­ethyl­idene­amino­oxy}acetic acid

Glidewell, C.; Low, J.N.; Skakle, J.M.S.; Wardell, J.L.

doi:10.1107/S1600536804019877

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 60| Part 9| September 2004| Pages o1560-o1562

https://doi.org/10.1107/S1600536804019877

Hydrogen-bonded R₂²(8) dimers in (E)-{[2-(phenyldiazenyl)phenyl]ethylideneaminooxy}acetic acid

Christopher Glidewell,^a ^* John N. Low,^b Janet M. S. Skakle ^b and James L. Wardell ^c

^aSchool of Chemistry, University of St Andrews, Fife KY16 9ST, Scotland, ^bDepartment of Chemistry, University of Aberdeen, Meston Walk, Old Aberdeen AB24 3UE, Scotland, and ^cInstituto de Química, Departamento de Química Inorgânica, Universidade Federal do Rio de Janeiro, 21945-970 Rio de Janeiro, RJ, Brazil
^*Correspondence e-mail: cg@st-andrews.ac.uk

(Received 9 August 2004; accepted 10 August 2004; online 21 August 2004)

Molecules of the title compound, C₁₆H₁₅N₃O₃, are linked by paired O—H⋯O hydrogen bonds [H⋯O = 1.84 Å, O⋯O = 2.655 (3) Å and O—H⋯O = 175°] into centrosymmetric R₂²(8) dimers.

Comment

Persulfate oxidation of iminooxyacetic acids, R(R′)C=NOCH₂COOH, provides a useful route to iminyl radicals (Forrester et al., 1979 ). The subsequent reactions of the iminyl radicals thus generated depend greatly on the substituents, and important species including nitrogen-containing heterocycles can result. We report here the crystal structure of the title compound, (I) (Fig. 1), and we compare (I) with the simpler analogues (II) and (III), whose structures we reported recently (Glidewell et al., 2004 ).

The C—O distances in the carboxyl group of (I) (Table 1) are consistent with the fully ordered location of the carboxyl H atom as deduced from a difference map. The distance O3—N4 corresponds exactly with the mean value for the —O—N= bond in oximes (Allen et al., 1987 ). The other distances are all typical of their types. The interbond angle at O3 is less than the idealized tetrahedral value, and those at N4, N11 and N12 are all significantly less than 120°, pointing in every case to the stereochemical influence of the unshared pairs of electrons. The angles at C5 indicate planarity at this atom. While the azobenzene fragment is effectively planar, as indicated by the key torsion angles (Table 1), the conformation of the side chain between O1 and C11 (Fig. 1) is not amenable to simple explanation. Compounds (I) and (III) have configurations at the C=N double bond [viz. (E) in (I) and (Z) in (III)] such that the sterically smaller substituent at C5 is on the same side as the OCH₂COOH substituent.

The molecules of (I) are linked by paired, and nearly linear, O—H⋯O hydrogen bonds (Table 2) into a centrosymmetric R₂²(8) (Bernstein et al., 1995 ) dimer, selected for the sake of convenience to lie across the inversion centre at (½, ½, ½) (Fig. 2). In this respect, the primary aggregation in (I) is the same at that in (II) and (III). The structure of (I) differs from that of (III), however, in that there are no direction-specific interactions between the dimers in (I), whereas those in (III) are linked into chains by a single aromatic π–π stacking interaction.

Figure 1
View of (I

), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.

Figure 2
Part of the crystal structure of (I

), showing the formation of an R₂²(8) dimer centred at (0.5, 0.5, 0.5). For the sake of clarity, H atoms bonded to C atoms have been omitted. Atoms marked with an asterisk (*) are at the symmetry position (1 − x, 1 − y, 1 − z).

Experimental

The title compound was prepared by reaction of ClCH₂CO₂H with the oxime derived from 2-(PhN=N)C₆H₄COCH₃ (Forrester et al., 1979), following the general procedure described recently (Glidewell et al., 2004). Crystals suitable for single-crystal X-ray diffraction were grown by slow evaporation of a solution in ethanol (m.p. 420–421 K).

Crystal data

C₁₆H₁₅N₃O₃
M_r = 297.31
Monoclinic, P2/c
a = 16.927 (2) Å
b = 4.5244 (5) Å
c = 19.673 (2) Å
β = 105.828 (5)°
V = 1449.5 (3) Å³
Z = 4
D_x = 1.362 Mg m⁻³
Mo Kα radiation
Cell parameters from 3256 reflections
θ = 3.7–27.6°
μ = 0.10 mm⁻¹
T = 120 (2) K
Block, colourless
0.24 × 0.18 × 0.10 mm

Data collection

Nonius KappaCCD diffractometer
φ scans, and ω scans with κ offsets
Absorption correction: multi-scan (SORTAV; Blessing, 1995 , 1997 ) T_min = 0.967, T_max = 0.990
13 640 measured reflections
3256 independent reflections
1443 reflections with I > 2σ(I)
R_int = 0.114
θ_max = 27.6°
h = −21 → 21
k = −5 → 5
l = −25 → 23

Refinement

Refinement on F²
R[F² > 2σ(F²)] = 0.069
wR(F²) = 0.187
S = 0.95
3256 reflections
201 parameters
H-atom parameters constrained
w = 1/[σ²(F_o²) + (0.0887P)²] where P = (F_o² + 2F_c²)/3
(Δ/σ)_max < 0.001
Δρ_max = 0.33 e Å⁻³
Δρ_min = −0.30 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

C1—O1	1.306 (4)
C1—O2	1.216 (4)
C1—C2	1.497 (5)
C2—O3	1.419 (4)
O3—N4	1.416 (3)
N4—C5	1.321 (4)

C2—O3—N4	107.6 (2)
O3—N4—C5	107.8 (2)
N12—N11—C12	114.1 (2)
N11—N12—C21	113.9 (3)
N4—C5—C6	126.8 (3)
N4—C5—C11	114.1 (3)
C6—C5—C11	119.0 (3)

O1—C1—C2—O3	157.5 (3)
C1—C2—O3—N4	83.0 (3)
C2—O3—N4—C5	174.9 (3)
O3—N4—C5—C11	176.4 (2)
N4—C5—C11—C12	114.9 (3)
C11—C12—N11—N12	−171.6 (3)
C12—N11—N12—C21	−177.0 (2)
N11—N12—C21—C22	−169.2 (3)

Table 2
Hydrogen-bonding geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯O2ⁱ	0.82	1.84	2.655 (3)	175
Symmetry code: (i) 1-x,1-y,1-z.

All H atoms were located in difference maps and then treated as riding atoms in idealized positions, with distances C—H = 0.95 (aromatic), 0.98 (CH₃) or 0.99 Å (CH₂), and O—H = 0.82 Å, and with U_iso(H) = 1.2U_eq(C,O) or 1.5U_eq(C_methyl). The low proportion (ca 44%) of the reflections labelled observed, even at 120 (2) K, together with the rather high merging index (0.11), are suggestive of poorly diffracting crystals, which may in turn be associated with the very limited intermolecular aggregation.

Data collection: KappaCCD Server Software (Nonius, 1997 ); cell refinement: DENZO–SMN (Otwinowski & Minor, 1997 ); data reduction: DENZO–SMN; program(s) used to solve structure: OSCAIL (McArdle, 2003 ) and SHELXS97 (Sheldrick, 1997 ); program(s) used to refine structure: OSCAIL and SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003 ); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536804019877/lh6263sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536804019877/lh6263Isup2.hkl

Computing details top

Data collection: KappaCCD Server Software (Nonius, 1997); cell refinement: DENZO–SMN (Otwinowski & Minor, 1997); data reduction: DENZO–SMN; program(s) used to solve structure: OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: OSCAIL and SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999).

(E)-{[2-(phenyldiazenyl)phenyl]ethylideneaminooxy}acetic acid top

Crystal data top

C₁₆H₁₅N₃O₃	F(000) = 624
M_r = 297.31	D_x = 1.362 Mg m⁻³
Monoclinic, P2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yc	Cell parameters from 3256 reflections
a = 16.927 (2) Å	θ = 3.7–27.6°
b = 4.5244 (5) Å	µ = 0.10 mm⁻¹
c = 19.673 (2) Å	T = 120 K
β = 105.828 (5)°	Block, colourless
V = 1449.5 (3) Å³	0.24 × 0.18 × 0.10 mm
Z = 4

Data collection top

Nonius KappaCCD diffractometer	3256 independent reflections
Radiation source: rotating anode	1443 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.114
φ scans, and ω scans with κ offsets	θ_max = 27.6°, θ_min = 3.7°
Absorption correction: multi-scan (SORTAV; Blessing, 1995, 1997)	h = −21→21
T_min = 0.967, T_max = 0.990	k = −5→5
13640 measured reflections	l = −25→23

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.069	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.187	H-atom parameters constrained
S = 0.95	w = 1/[σ²(F_o²) + (0.0887P)²] where P = (F_o² + 2F_c²)/3
3256 reflections	(Δ/σ)_max < 0.001
201 parameters	Δρ_max = 0.33 e Å⁻³
0 restraints	Δρ_min = −0.30 e Å⁻³

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.46906 (14)	0.7971 (5)	0.54731 (11)	0.0437 (6)
O2	0.55689 (14)	0.4231 (6)	0.58201 (11)	0.0434 (6)
O3	0.57470 (13)	0.5937 (6)	0.72230 (11)	0.0446 (6)
N4	0.66025 (15)	0.5730 (7)	0.73040 (13)	0.0393 (7)
N11	0.80586 (15)	0.6485 (6)	0.90340 (12)	0.0324 (7)
N12	0.85988 (16)	0.7732 (6)	0.95175 (13)	0.0344 (7)
C1	0.52388 (19)	0.6478 (8)	0.59434 (16)	0.0356 (8)
C2	0.5416 (2)	0.7907 (8)	0.66556 (16)	0.0454 (9)
C5	0.69242 (19)	0.4093 (7)	0.78678 (15)	0.0334 (8)
C6	0.6478 (2)	0.2676 (8)	0.83366 (17)	0.0444 (9)
C11	0.78107 (19)	0.3522 (7)	0.79952 (15)	0.0319 (8)
C12	0.83809 (18)	0.4609 (7)	0.85880 (14)	0.0299 (7)
C13	0.9206 (2)	0.3874 (8)	0.87194 (17)	0.0396 (9)
C14	0.9458 (2)	0.2030 (8)	0.82658 (17)	0.0443 (9)
C15	0.8899 (2)	0.0953 (8)	0.76677 (17)	0.0430 (9)
C16	0.8080 (2)	0.1681 (8)	0.75322 (16)	0.0382 (8)
C21	0.82756 (19)	0.9473 (7)	0.99800 (14)	0.0322 (8)
C22	0.8830 (2)	1.1286 (7)	1.04418 (15)	0.0373 (8)
C23	0.8578 (2)	1.2983 (8)	1.09284 (16)	0.0415 (9)
C24	0.7775 (2)	1.2874 (8)	1.09551 (16)	0.0437 (9)
C25	0.7221 (2)	1.1054 (8)	1.04992 (17)	0.0439 (9)
C26	0.7466 (2)	0.9344 (7)	1.00096 (16)	0.0374 (8)
H1	0.4617	0.7184	0.5085	0.052*
H2A	0.5801	0.9515	0.6676	0.054*
H2B	0.4912	0.8748	0.6715	0.054*
H6A	0.5898	0.2978	0.8145	0.067*
H6B	0.6653	0.3540	0.8799	0.067*
H6C	0.6593	0.0595	0.8368	0.067*
H13	0.9587	0.4631	0.9115	0.048*
H14	1.0009	0.1502	0.8362	0.053*
H15	0.9076	−0.0262	0.7357	0.052*
H16	0.7705	0.0944	0.7131	0.046*
H22	0.9373	1.1364	1.0425	0.045*
H23	0.8952	1.4201	1.1238	0.050*
H24	0.7605	1.4027	1.1281	0.052*
H25	0.6679	1.0976	1.0521	0.053*
H26	0.7091	0.8118	0.9703	0.045*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0491 (14)	0.0479 (16)	0.0282 (12)	0.0134 (12)	0.0006 (11)	0.0019 (11)
O2	0.0488 (15)	0.0421 (16)	0.0332 (12)	0.0099 (12)	0.0011 (11)	0.0013 (11)
O3	0.0356 (14)	0.0591 (17)	0.0381 (13)	0.0006 (12)	0.0087 (10)	0.0011 (11)
N4	0.0253 (15)	0.0535 (19)	0.0371 (15)	−0.0034 (13)	0.0053 (12)	−0.0110 (14)
N11	0.0368 (16)	0.0308 (16)	0.0259 (13)	−0.0019 (13)	0.0020 (12)	−0.0003 (12)
N12	0.0359 (15)	0.0373 (17)	0.0276 (13)	−0.0019 (13)	0.0046 (12)	−0.0003 (12)
C1	0.0306 (19)	0.041 (2)	0.0333 (18)	−0.0016 (17)	0.0063 (15)	0.0072 (16)
C2	0.049 (2)	0.052 (2)	0.0281 (17)	0.0165 (18)	−0.0006 (15)	0.0035 (16)
C5	0.039 (2)	0.0326 (19)	0.0235 (15)	−0.0021 (15)	0.0005 (14)	−0.0035 (14)
C6	0.0361 (19)	0.051 (2)	0.0418 (19)	−0.0008 (17)	0.0028 (16)	−0.0037 (17)
C11	0.0352 (19)	0.0347 (19)	0.0239 (15)	−0.0021 (15)	0.0048 (14)	0.0045 (14)
C12	0.0324 (19)	0.0313 (18)	0.0248 (15)	−0.0037 (14)	0.0058 (14)	0.0009 (14)
C13	0.036 (2)	0.047 (2)	0.0341 (17)	−0.0071 (16)	0.0064 (15)	−0.0066 (16)
C14	0.038 (2)	0.052 (2)	0.045 (2)	−0.0031 (17)	0.0136 (17)	−0.0035 (18)
C15	0.047 (2)	0.046 (2)	0.0396 (19)	−0.0021 (18)	0.0177 (17)	−0.0096 (16)
C16	0.045 (2)	0.042 (2)	0.0256 (16)	−0.0035 (17)	0.0061 (15)	−0.0013 (15)
C21	0.0335 (19)	0.0349 (19)	0.0246 (15)	0.0007 (15)	0.0020 (14)	0.0025 (14)
C22	0.040 (2)	0.040 (2)	0.0279 (16)	−0.0051 (16)	0.0037 (15)	−0.0004 (15)
C23	0.049 (2)	0.039 (2)	0.0313 (17)	−0.0086 (17)	0.0019 (16)	−0.0012 (16)
C24	0.063 (3)	0.038 (2)	0.0303 (18)	0.0054 (18)	0.0146 (18)	−0.0007 (15)
C25	0.041 (2)	0.047 (2)	0.043 (2)	0.0021 (18)	0.0108 (17)	0.0007 (17)
C26	0.041 (2)	0.037 (2)	0.0297 (17)	−0.0004 (16)	0.0039 (15)	0.0002 (15)

Geometric parameters (Å, º) top

C1—O1	1.306 (4)	C13—H13	0.93
C1—O2	1.216 (4)	C14—C15	1.382 (5)
C1—C2	1.497 (5)	C14—H14	0.93
O1—H1	0.82	C15—C16	1.378 (5)
C2—O3	1.419 (4)	C15—H15	0.93
C2—H2A	0.97	C16—H16	0.93
C2—H2B	0.97	N11—N12	1.259 (3)
O3—N4	1.416 (3)	N12—C21	1.421 (4)
N4—C5	1.321 (4)	C21—C22	1.383 (4)
C5—C11	1.475 (4)	C21—C26	1.389 (4)
C5—C6	1.488 (5)	C22—C23	1.382 (4)
C6—H6A	0.96	C22—H22	0.93
C6—H6B	0.96	C23—C24	1.376 (5)
C6—H6C	0.96	C23—H23	0.93
C11—C12	1.385 (4)	C24—C25	1.380 (5)
C11—C16	1.400 (4)	C24—H24	0.93
C12—C13	1.389 (4)	C25—C26	1.384 (4)
C12—N11	1.431 (4)	C25—H25	0.93
C13—C14	1.372 (5)	C26—H26	0.93

O2—C1—O1	124.6 (3)	C14—C13—H13	120.0
O2—C1—C2	124.2 (3)	C12—C13—H13	120.0
O1—C1—C2	111.2 (3)	C13—C14—C15	120.4 (3)
C1—O1—H1	109.5	C13—C14—H14	119.8
O3—C2—C1	113.6 (3)	C15—C14—H14	119.8
O3—C2—H2A	108.8	C16—C15—C14	119.9 (3)
C1—C2—H2A	108.8	C16—C15—H15	120.0
O3—C2—H2B	108.8	C14—C15—H15	120.0
C1—C2—H2B	108.8	C15—C16—C11	120.4 (3)
H2A—C2—H2B	107.7	C15—C16—H16	119.8
C2—O3—N4	107.6 (2)	C11—C16—H16	119.8
O3—N4—C5	107.8 (2)	C22—C21—C26	119.8 (3)
N12—N11—C12	114.1 (2)	C22—C21—N12	116.1 (3)
N11—N12—C21	113.9 (3)	C26—C21—N12	124.1 (3)
N4—C5—C6	126.8 (3)	C23—C22—C21	120.2 (3)
N4—C5—C11	114.1 (3)	C23—C22—H22	119.9
C6—C5—C11	119.0 (3)	C21—C22—H22	119.9
C5—C6—H6A	109.5	C24—C23—C22	120.0 (3)
C5—C6—H6B	109.5	C24—C23—H23	120.0
H6A—C6—H6B	109.5	C22—C23—H23	120.0
C5—C6—H6C	109.5	C23—C24—C25	120.0 (3)
H6A—C6—H6C	109.5	C23—C24—H24	120.0
H6B—C6—H6C	109.5	C25—C24—H24	120.0
C12—C11—C16	118.9 (3)	C24—C25—C26	120.4 (3)
C12—C11—C5	121.6 (3)	C24—C25—H25	119.8
C16—C11—C5	119.4 (3)	C26—C25—H25	119.8
C11—C12—C13	120.4 (3)	C25—C26—C21	119.5 (3)
C11—C12—N11	115.6 (3)	C25—C26—H26	120.3
C13—C12—N11	124.0 (3)	C21—C26—H26	120.3
C14—C13—C12	120.0 (3)

O2—C1—C2—O3	−23.1 (5)	C13—C14—C15—C16	−1.4 (5)
O1—C1—C2—O3	157.5 (3)	C14—C15—C16—C11	0.4 (5)
C1—C2—O3—N4	83.0 (3)	C12—C11—C16—C15	0.4 (5)
C2—O3—N4—C5	174.9 (3)	C5—C11—C16—C15	−175.5 (3)
O3—N4—C5—C11	176.4 (2)	C11—C12—N11—N12	−171.6 (3)
O3—N4—C5—C6	0.6 (4)	C13—C12—N11—N12	8.3 (4)
N4—C5—C11—C12	114.9 (3)	C12—N11—N12—C21	−177.0 (2)
C6—C5—C11—C12	−68.9 (4)	N11—N12—C21—C22	−169.2 (3)
N4—C5—C11—C16	−69.4 (4)	N11—N12—C21—C26	13.7 (4)
C6—C5—C11—C16	106.8 (3)	C26—C21—C22—C23	−0.5 (5)
C16—C11—C12—C13	−0.1 (4)	N12—C21—C22—C23	−177.7 (3)
C5—C11—C12—C13	175.6 (3)	C21—C22—C23—C24	0.0 (5)
C16—C11—C12—N11	179.8 (3)	C22—C23—C24—C25	0.4 (5)
C5—C11—C12—N11	−4.5 (4)	C23—C24—C25—C26	−0.4 (5)
C11—C12—C13—C14	−0.9 (5)	C24—C25—C26—C21	0.0 (5)
N11—C12—C13—C14	179.3 (3)	C22—C21—C26—C25	0.5 (5)
C12—C13—C14—C15	1.6 (5)	N12—C21—C26—C25	177.5 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O2ⁱ	0.82	1.84	2.655 (3)	175

Symmetry code: (i) −x+1, −y+1, −z+1.

Acknowledgements

X-ray data were collected at the EPSRC X-ray Crystallographic Service, University of Southampton, England. The authors thank the staff for all their help and advice. JNL thanks NCR Self-Service, Dundee, for grants which have provided computing facilities for this work. JLW thanks CNPq and FAPERJ for financial support.

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ISSN: 2056-9890

Volume 60| Part 9| September 2004| Pages o1560-o1562

https://doi.org/10.1107/S1600536804019877

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