The 2-methoxy­phenyl­hydrazone derivative of de­hydro­ascorbic acid

The title compound, (3Z)-5-(1,2-di­hydroxy­ethyl)­furan-2,3,4(3H,5H)-trione 3-[(2-methoxy­phenyl)­hydrazone], C₁₃H₁₄N₂O₆, is produced when de­hydro-L-ascorbic acid reacts with 2-methoxy­phenyl­hydrazine. A two-dimensional structure is generated by extensive hydrogen-bonding interactions.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.013 Å
• R factor = 0.073
• wR factor = 0.221
• Data-to-parameter ratio = 8.2

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT340_ALERT_3_B Low Bond Precision on C-C bonds (x 1000) Ang..         13

Alert level C
PLAT155_ALERT_4_C The Triclinic Unitcell is NOT Reduced ........          ?
PLAT156_ALERT_4_C Axial System Input Cell not Standard .........          ?

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.50
           From the CIF: _reflns_number_total               1575
           Count of symmetry unique reflns         1577
           Completeness (_total/calc)             99.87%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present           no

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 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
   3 ALERT type 4 Improvement, methodology, query or suggestion

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S1. Comment

Vegetables and fruit may turn red–brown when they are kept under aerobic conditions for a long time. A mechanism proposed to account for this indicated that reactions of dehydroascorbic acid with amino acids play an important role in the process of oxidation of L-ascorbic acid to 2,2'-nitrilo-di-2(2')-deoxy-L-ascorbic acid monoammonium salt, which is red–brown (Kurata et al., 1973a,b).

In the course of structural studies of the red–brown pigment, the hydrazones were prepared by reaction of dehydroascorbic acid with hydrazines. Among eight hydrazones synthesized, the crystal structures of 2-methoxyphenylhydrazone dehydroascorbic acid, (I), was determined by single-crystal X-ray diffraction methods (Fig. 1 and Table 1).

The molecular structure of (I) comprises an ethylene glycol open chain linked to the hydrazone group via a lactone ring. The 15 non-H atoms of the phenylhydrazone and lactone ring are effectively coplanar, with the maximum deviation from the least-squares plane through these atoms being 0.066 (9) Å for C8. The bond lengths and angles in (I) are quite similar to those reported for the closely related structure of p-bromophenylhydrazone dehydroascorbic acid (Hvoslef & Nordenson, 1976).

The hydrogen-bonding distances and angles are listed in Table 2. An intramolecular N2—H···O2 hydrogen bond is observed. Both of the OH groups of the ethylene glycol residue participate in hydrogen bonds. The terminal OH group (O5) is connected to the carbonyl atom O3. These interactions link the molecules into ribbons that are aligned along the a axis, as shown in Fig. 2. The ribbons are stacked along [011] and are connected by hydrogen bonds formed between two OH groups (O3—H···O5). The stacking distance between ribbons is approximately 3.4 Å. The intermolecular hydrogen bonds described above combine to generate a two-dimensional layer structure.

S2. Experimental

The title compound was prepared according to a literature procedure (Hvoslef & Nordenson (1976). Plate-like yellow crystals were obtained from recrystallization from an ethanol solution of the compound.

S3. Refinement

All H atoms were included in the riding-model approximation, with U_iso(methyl-H, hydroxy-H) = 1.5U_eq(parent atom) and U_iso(H) = 1.2U_eq(parent atom). Friedel pairs were merged and Δf'' term was set to zero. Thus, the calculated absolute structure parameter of 0(10) (Flack, 1983) is meaningless in this analysis.

Computing details

Data collection: MSC/AFC Diffractometer Control Software (Molecular Structure Corporation, 1992); cell refinement: MSC/AFC Diffractometer Control Software; data reduction: TEXSAN (Molecular Structure Corporation, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Speck, 2003) and Mercury (CCDC, 2003); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. Displacement ellipsoid drawing at the 50% probability level showing the atom-labelling scheme.
	Fig. 2. A perspective packing diagram. Dotted lines indicate the intermolecular hydrogen-bonding interactions.

(3Z)-5-(1,2-dihydroxyethyl) −2,3,4(5H)-furantrione 3-[(2-methoxyphenyl)hydrazone]

Crystal data

C13H14N2O6	Z = 1
Mr = 294.26	F(000) = 154
Triclinic, P1	Dx = 1.418 Mg m^−3
Hall symbol: P 1	Mo Kα radiation, λ = 0.71069 Å
a = 8.194 (2) Å	Cell parameters from 25 reflections
b = 8.308 (2) Å	θ = 28.0–30.0°
c = 5.463 (3) Å	µ = 0.11 mm^−1
α = 106.12 (3)°	T = 295 K
β = 101.98 (3)°	Plate, clear pale yellow
γ = 95.69 (2)°	0.30 × 0.15 × 0.05 mm
V = 344.6 (2) Å^3

Data collection

Rigaku AFC-7S diffractometer	961 reflections with I > 2σ(I)'
Radiation source: fine-focus sealed tube	Rint = 0.030
Graphite monochromator	θmax = 27.5°, θmin = 2.6°
q–2θ scans	h = 0→10
Absorption correction: psi scan (North et al., 1968)	k = −10→10
Tmin = 0.960, Tmax = 0.998	l = −7→6
1680 measured reflections	3 standard reflections every 150 reflections
1575 independent reflections	intensity decay: 0.8%

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)] = 0.073	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.221	H-atom parameters constrained
S = 1.05	w = 1/[σ^2(Fo^2) + (0.0983P)^2 + 0.4777P] where P = (Fo^2 + 2Fc^2)/3
1575 reflections	(Δ/σ)max < 0.001
193 parameters	Δρmax = 0.31 e Å^−3
3 restraints	Δρmin = −0.30 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
C1	0.4426 (10)	0.5773 (9)	0.3686 (16)	0.050 (2)
C2	0.6015 (11)	0.5223 (10)	0.3550 (17)	0.054 (2)
O1	0.5632 (7)	0.7339 (7)	0.1498 (10)	0.0518 (15)
C3	0.6861 (10)	0.6288 (11)	0.2206 (16)	0.0476 (19)
H3	0.7123	0.5567	0.0632	0.057*
C4	0.4256 (11)	0.7107 (10)	0.2478 (15)	0.051 (2)
O2	0.6631 (8)	0.4145 (8)	0.4432 (14)	0.0678 (19)
O3	0.3158 (7)	0.7941 (8)	0.2163 (14)	0.0679 (19)
C5	0.8457 (9)	0.7414 (10)	0.4088 (15)	0.0467 (19)
H5	0.9269	0.6699	0.4576	0.056*
O4	0.7992 (8)	0.8347 (8)	0.6371 (11)	0.0624 (17)
H4	0.8535	0.8149	0.7664	0.094*
C6	0.9284 (10)	0.8667 (12)	0.2985 (17)	0.055 (2)
H6A	0.8504	0.9414	0.2571	0.066*
H6B	1.0281	0.9359	0.4285	0.066*
O5	0.9750 (8)	0.7782 (10)	0.0684 (13)	0.070 (2)
H5A	1.0761	0.7729	0.1047	0.105*
N1	0.3299 (8)	0.5304 (8)	0.4909 (13)	0.0486 (17)
N2	0.3639 (9)	0.4106 (8)	0.5937 (13)	0.0497 (17)
H2	0.4559	0.3709	0.5818	0.060*
C7	0.2568 (11)	0.3431 (10)	0.7237 (16)	0.052 (2)
C8	0.1011 (13)	0.3893 (12)	0.7335 (19)	0.065 (3)
H8	0.0612	0.4661	0.6497	0.078*
C9	0.0057 (13)	0.3198 (13)	0.870 (2)	0.070 (3)
H9	−0.0982	0.3524	0.8836	0.085*
C10	0.0631 (13)	0.2033 (12)	0.984 (2)	0.066 (3)
H10	−0.0042	0.1557	1.0725	0.080*
C11	0.2164 (13)	0.1544 (10)	0.9740 (17)	0.058 (2)
H11	0.2546	0.0764	1.0567	0.070*
C12	0.3128 (11)	0.2230 (10)	0.8386 (18)	0.055 (2)
O13	0.4690 (8)	0.1896 (8)	0.8125 (14)	0.0701 (19)
C14	0.5285 (15)	0.0537 (14)	0.901 (2)	0.079 (3)
H14A	0.5451	0.0830	1.0879	0.118*
H14B	0.6337	0.0353	0.8553	0.118*
H14C	0.4464	−0.0481	0.8177	0.118*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.046 (5)	0.035 (4)	0.060 (5)	0.005 (3)	−0.010 (4)	0.021 (4)
C2	0.054 (5)	0.039 (4)	0.061 (5)	0.013 (4)	−0.005 (4)	0.014 (4)
O1	0.040 (3)	0.067 (4)	0.056 (3)	0.008 (3)	0.000 (2)	0.038 (3)
C3	0.042 (4)	0.057 (5)	0.046 (4)	0.009 (4)	0.004 (3)	0.024 (4)
C4	0.053 (5)	0.051 (5)	0.047 (5)	−0.002 (4)	−0.004 (4)	0.027 (4)
O2	0.056 (4)	0.057 (4)	0.100 (5)	0.020 (3)	0.007 (3)	0.044 (4)
O3	0.040 (3)	0.074 (4)	0.108 (5)	0.020 (3)	0.010 (3)	0.060 (4)
C5	0.041 (4)	0.051 (4)	0.048 (5)	0.016 (3)	−0.001 (3)	0.022 (4)
O4	0.058 (4)	0.073 (4)	0.050 (3)	0.011 (3)	0.000 (3)	0.019 (3)
C6	0.044 (4)	0.069 (6)	0.049 (5)	0.000 (4)	−0.002 (4)	0.026 (4)
O5	0.043 (3)	0.112 (6)	0.066 (4)	0.011 (3)	0.006 (3)	0.048 (4)
N1	0.054 (4)	0.041 (3)	0.050 (4)	−0.003 (3)	−0.003 (3)	0.027 (3)
N2	0.048 (4)	0.047 (4)	0.057 (4)	0.006 (3)	0.000 (3)	0.029 (3)
C7	0.061 (5)	0.037 (4)	0.051 (5)	0.005 (4)	−0.007 (4)	0.018 (4)
C8	0.070 (6)	0.054 (5)	0.071 (7)	0.011 (5)	0.002 (5)	0.031 (5)
C9	0.061 (6)	0.067 (6)	0.087 (7)	0.013 (5)	0.011 (5)	0.035 (6)
C10	0.069 (6)	0.054 (5)	0.078 (7)	0.001 (5)	0.010 (5)	0.033 (5)
C11	0.084 (7)	0.036 (4)	0.050 (5)	0.002 (4)	0.000 (4)	0.020 (4)
C12	0.054 (5)	0.033 (4)	0.065 (5)	0.005 (4)	−0.012 (4)	0.013 (4)
O13	0.063 (4)	0.066 (4)	0.091 (5)	0.018 (3)	0.008 (3)	0.047 (4)
C14	0.082 (7)	0.062 (6)	0.104 (8)	0.039 (6)	0.014 (6)	0.041 (6)

Geometric parameters (Å, º)

C1—N1	1.334 (11)	N1—N2	1.298 (8)
C1—C2	1.431 (12)	N2—C7	1.404 (11)
C1—C4	1.443 (10)	N2—H2	0.8600
C2—O2	1.232 (9)	C7—C8	1.375 (13)
C2—C3	1.501 (12)	C7—C12	1.386 (11)
O1—C4	1.363 (10)	C8—C9	1.374 (14)
O1—C3	1.458 (10)	C8—H8	0.9300
C3—C5	1.519 (11)	C9—C10	1.362 (13)
C3—H3	0.9800	C9—H9	0.9300
C4—O3	1.202 (10)	C10—C11	1.366 (14)
C5—O4	1.421 (10)	C10—H10	0.9300
C5—C6	1.511 (11)	C11—C12	1.372 (13)
C5—H5	0.9800	C11—H11	0.9300
O4—H4	0.8200	C12—O13	1.364 (11)
C6—O5	1.417 (11)	O13—C14	1.434 (10)
C6—H6A	0.9700	C14—H14A	0.9600
C6—H6B	0.9700	C14—H14B	0.9600
O5—H5A	0.8200	C14—H14C	0.9600
N1—C1—C2	128.3 (7)	N2—N1—C1	115.3 (7)
N1—C1—C4	122.4 (7)	N1—N2—C7	122.8 (7)
C2—C1—C4	109.0 (8)	N1—N2—H2	118.6
O2—C2—C1	128.2 (9)	C7—N2—H2	118.6
O2—C2—C3	125.4 (8)	C8—C7—C12	120.6 (9)
C1—C2—C3	106.4 (7)	C8—C7—N2	122.4 (7)
C4—O1—C3	110.9 (6)	C12—C7—N2	117.0 (8)
O1—C3—C2	104.9 (6)	C9—C8—C7	118.7 (8)
O1—C3—C5	109.7 (6)	C9—C8—H8	120.7
C2—C3—C5	110.3 (6)	C7—C8—H8	120.7
O1—C3—H3	110.6	C10—C9—C8	120.1 (10)
C2—C3—H3	110.6	C10—C9—H9	119.9
C5—C3—H3	110.6	C8—C9—H9	119.9
O3—C4—O1	119.1 (7)	C9—C10—C11	122.0 (9)
O3—C4—C1	132.2 (8)	C9—C10—H10	119.0
O1—C4—C1	108.6 (7)	C11—C10—H10	119.0
O4—C5—C6	108.1 (7)	C10—C11—C12	118.4 (8)
O4—C5—C3	107.3 (6)	C10—C11—H11	120.8
C6—C5—C3	113.7 (6)	C12—C11—H11	120.8
O4—C5—H5	109.2	O13—C12—C11	125.8 (8)
C6—C5—H5	109.2	O13—C12—C7	114.0 (8)
C3—C5—H5	109.2	C11—C12—C7	120.2 (9)
C5—O4—H4	109.5	C12—O13—C14	117.5 (8)
O5—C6—C5	109.8 (7)	O13—C14—H14A	109.5
O5—C6—H6A	109.7	O13—C14—H14B	109.5
C5—C6—H6A	109.7	H14A—C14—H14B	109.5
O5—C6—H6B	109.7	O13—C14—H14C	109.5
C5—C6—H6B	109.7	H14A—C14—H14C	109.5
H6A—C6—H6B	108.2	H14B—C14—H14C	109.5
C6—O5—H5A	109.5
N1—C1—C2—O2	3.7 (14)	O4—C5—C6—O5	−179.4 (6)
C4—C1—C2—O2	177.8 (9)	C3—C5—C6—O5	−60.3 (8)
N1—C1—C2—C3	−173.6 (8)	C2—C1—N1—N2	−5.5 (11)
C4—C1—C2—C3	0.4 (9)	C4—C1—N1—N2	−178.8 (7)
C4—O1—C3—C2	5.3 (8)	C1—N1—N2—C7	−178.4 (7)
C4—O1—C3—C5	−113.1 (7)	N1—N2—C7—C8	5.3 (12)
O2—C2—C3—O1	179.2 (8)	N1—N2—C7—C12	−176.2 (7)
C1—C2—C3—O1	−3.3 (8)	C12—C7—C8—C9	2.9 (13)
O2—C2—C3—C5	−62.7 (12)	N2—C7—C8—C9	−178.6 (9)
C1—C2—C3—C5	114.7 (7)	C7—C8—C9—C10	−2.2 (15)
C3—O1—C4—O3	176.7 (8)	C8—C9—C10—C11	1.4 (16)
C3—O1—C4—C1	−5.2 (8)	C9—C10—C11—C12	−1.4 (15)
N1—C1—C4—O3	−4.9 (14)	C10—C11—C12—O13	179.0 (9)
C2—C1—C4—O3	−179.4 (9)	C10—C11—C12—C7	2.1 (12)
N1—C1—C4—O1	177.4 (7)	C8—C7—C12—O13	179.8 (8)
C2—C1—C4—O1	2.9 (8)	N2—C7—C12—O13	1.3 (10)
O1—C3—C5—O4	60.9 (7)	C8—C7—C12—C11	−2.9 (12)
C2—C3—C5—O4	−54.1 (8)	N2—C7—C12—C11	178.5 (8)
O1—C3—C5—C6	−58.6 (9)	C11—C12—O13—C14	9.5 (13)
C2—C3—C5—C6	−173.7 (7)	C7—C12—O13—C14	−173.4 (8)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2···O2	0.86	2.04	2.743 (10)	139
O4—H4···O5^i	0.82	1.86	2.680 (8)	178
O5—H5A···O3^ii	0.82	1.91	2.721 (8)	172

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