Ethyl 3-(3-eth­oxy-2-hydroxy­benzyl­idene)carbazate

In the title compound, C₁₂H₁₆N₂O₄, an intra­molecular O—H...O hydrogen bond occurs. In the crystal, mol­ecules are linked by N—H...O hydrogen bonds, forming chains propagating in the [010] direction.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.035
• wR factor = 0.090
• Data-to-parameter ratio = 17.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          2
PLAT024_ALERT_4_C Merging of Friedel Pairs is Indicated ..........          !
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          1
              C12 H16 N2 O4

Alert level G
REFLT03_ALERT_4_G  ALERT: MoKa measured Friedel data cannot be used to
                   determine absolute structure in a light-atom
                   study EXCEPT under VERY special conditions.
                   It is preferred that Friedel data is merged in such cases.
           From the CIF: _diffrn_reflns_theta_max           27.48
           From the CIF: _reflns_number_total               2917
           Count of symmetry unique reflns         1699
           Completeness (_total/calc)            171.69%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      1218
           Fraction of Friedel pairs measured     0.717
           Are heavy atom types Z>Si present         no
PLAT180_ALERT_4_G Check Cell Rounding: # of Values Ending with 0 =          3
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported   _diffrn_ambient_temperature        293 K

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

   2 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
   4 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check


checkCIF publication errors

Alert level G
PUBL013_ALERT_1_G The _publ_section_comment (discussion of study) is
            missing. This is required for a full paper submission (but is
            optional for an electronic paper).

   0 ALERT level A = Data missing that is essential or data in wrong format
   1 ALERT level G = General alerts. Data that may be required is missing

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Related literature

For background to Schiff bases, see: Cimerman et al. (1997).

S1. Experimental

A mixture of 3-ethoxy-2-hydroxybenzaldehyde (0.1 mol), and ethyl carbazate (0.1 mol) was stirred in refluxing ethanol (20 ml) for 4 h to afford the title compound (0.082 mol, yield 82%). Colourless blocks of (I) were obtained by recrystallization from ethanol at room temperature.

S2. Refinement

Refinement of the Flack absolute structure parameter was indeterminate.

H atoms were fixed geometrically (C—H = 0.93–0.97Å, O—H = 0.82Å, N—H = 0.86Å) and refined as riding with U_iso(H) = 1.2–1.5U_eq(carrier).

Structure description

For background to Schiff bases, see: Cimerman et al. (1997).

Computing details

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures

Fig. 1. The molecular structure of (I) showing 30% probability displacement ellipsoids.

Ethyl 3-(3-ethoxy-2-hydroxybenzylidene)carbazate

Crystal data

C12H16N2O4	F(000) = 536
Mr = 252.27	Dx = 1.321 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 1982 reflections
a = 7.1140 (14) Å	θ = 3.5–27.3°
b = 9.6010 (19) Å	µ = 0.10 mm^−1
c = 18.570 (4) Å	T = 293 K
V = 1268.4 (4) Å^3	Block, colourless
Z = 4	0.22 × 0.20 × 0.19 mm

Data collection

Bruker SMART CCD diffractometer	2680 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.043
Graphite monochromator	θmax = 27.5°, θmin = 3.1°
ω scans	h = −8→9
11976 measured reflections	k = −12→12
2917 independent reflections	l = −23→24

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)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.090	H-atom parameters constrained
S = 1.07	w = 1/[σ^2(Fo^2) + (0.0474P)^2 + 0.0849P] where P = (Fo^2 + 2Fc^2)/3
2917 reflections	(Δ/σ)max < 0.001
163 parameters	Δρmax = 0.14 e Å^−3
0 restraints	Δρmin = −0.18 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
O1	0.32636 (13)	0.00340 (9)	0.17092 (5)	0.0507 (3)
N2	0.73581 (14)	−0.03948 (10)	0.26990 (6)	0.0400 (2)
O4	0.90478 (14)	−0.23476 (9)	0.34513 (6)	0.0514 (3)
H4A	0.8193	−0.2008	0.3212	0.077*
N1	0.59340 (15)	0.01343 (11)	0.22830 (6)	0.0447 (3)
H1A	0.5964	0.0986	0.2140	0.054*
O2	0.43343 (15)	−0.19175 (9)	0.22560 (6)	0.0530 (3)
C3	0.44812 (18)	−0.07057 (13)	0.21020 (7)	0.0398 (3)
O3	1.19430 (15)	−0.31435 (11)	0.41917 (6)	0.0563 (3)
C10	1.04046 (17)	−0.13798 (13)	0.35560 (7)	0.0379 (3)
C4	0.87138 (19)	0.04316 (13)	0.28510 (7)	0.0418 (3)
H4B	0.8679	0.1344	0.2684	0.050*
C5	1.03034 (18)	−0.00269 (13)	0.32791 (7)	0.0396 (3)
C8	1.3410 (2)	−0.08581 (17)	0.40856 (8)	0.0522 (3)
H8A	1.4449	−0.1125	0.4356	0.063*
C9	1.1983 (2)	−0.17984 (14)	0.39607 (7)	0.0433 (3)
C11	1.3491 (2)	−0.36144 (18)	0.46182 (8)	0.0569 (4)
H11A	1.3584	−0.3070	0.5057	0.068*
H11B	1.4657	−0.3519	0.4352	0.068*
C6	1.1784 (2)	0.08977 (15)	0.34131 (8)	0.0500 (3)
H6A	1.1732	0.1799	0.3231	0.060*
C2	0.1594 (2)	−0.06859 (15)	0.14570 (9)	0.0503 (3)
H2B	0.0623	−0.0007	0.1351	0.060*
H2C	0.1131	−0.1291	0.1836	0.060*
C7	1.3308 (2)	0.04877 (18)	0.38097 (9)	0.0583 (4)
H7A	1.4282	0.1112	0.3895	0.070*
C12	1.3135 (3)	−0.51120 (19)	0.47940 (11)	0.0702 (5)
H12A	1.4159	−0.5468	0.5076	0.105*
H12B	1.3032	−0.5638	0.4356	0.105*
H12C	1.1987	−0.5191	0.5063	0.105*
C1	0.1972 (3)	−0.1532 (2)	0.08008 (10)	0.0710 (5)
H1B	0.0839	−0.1994	0.0654	0.106*
H1C	0.2922	−0.2212	0.0905	0.106*
H1D	0.2399	−0.0933	0.0420	0.106*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0523 (5)	0.0346 (5)	0.0654 (6)	0.0008 (4)	−0.0193 (5)	0.0033 (4)
N2	0.0422 (5)	0.0344 (5)	0.0433 (5)	0.0040 (4)	−0.0032 (4)	0.0007 (4)
O4	0.0488 (5)	0.0345 (5)	0.0708 (6)	−0.0054 (4)	−0.0190 (5)	0.0043 (4)
N1	0.0486 (6)	0.0311 (5)	0.0545 (6)	0.0019 (4)	−0.0116 (5)	0.0051 (4)
O2	0.0618 (6)	0.0288 (4)	0.0683 (6)	0.0011 (4)	−0.0139 (5)	0.0029 (4)
C3	0.0454 (6)	0.0310 (5)	0.0429 (6)	0.0050 (5)	−0.0035 (6)	−0.0037 (5)
O3	0.0554 (6)	0.0443 (5)	0.0693 (6)	0.0021 (4)	−0.0214 (5)	0.0068 (4)
C10	0.0393 (6)	0.0355 (6)	0.0387 (6)	−0.0011 (5)	−0.0014 (5)	−0.0041 (5)
C4	0.0484 (6)	0.0325 (6)	0.0445 (6)	0.0012 (5)	0.0015 (6)	0.0015 (5)
C5	0.0413 (6)	0.0398 (6)	0.0376 (6)	−0.0017 (5)	0.0014 (5)	−0.0025 (5)
C8	0.0446 (7)	0.0583 (9)	0.0535 (8)	−0.0041 (6)	−0.0122 (7)	−0.0008 (6)
C9	0.0457 (7)	0.0416 (7)	0.0426 (6)	0.0011 (5)	−0.0049 (6)	−0.0016 (5)
C11	0.0536 (8)	0.0620 (9)	0.0550 (8)	0.0109 (7)	−0.0132 (7)	0.0057 (7)
C6	0.0533 (8)	0.0414 (7)	0.0554 (8)	−0.0104 (6)	−0.0007 (7)	0.0036 (6)
C2	0.0455 (7)	0.0405 (7)	0.0647 (8)	0.0012 (6)	−0.0117 (7)	−0.0035 (6)
C7	0.0506 (8)	0.0592 (9)	0.0650 (9)	−0.0189 (7)	−0.0082 (7)	−0.0003 (7)
C12	0.0665 (10)	0.0650 (10)	0.0791 (11)	0.0153 (9)	−0.0034 (9)	0.0201 (9)
C1	0.0691 (10)	0.0819 (12)	0.0618 (9)	0.0041 (10)	−0.0130 (9)	−0.0153 (9)

Geometric parameters (Å, º)

O1—C3	1.3367 (15)	C8—C7	1.392 (2)
O1—C2	1.4516 (17)	C8—H8A	0.9300
N2—C4	1.2803 (17)	C11—C12	1.496 (3)
N2—N1	1.3715 (14)	C11—H11A	0.9700
O4—C10	1.3539 (15)	C11—H11B	0.9700
O4—H4A	0.8200	C6—C7	1.368 (2)
N1—C3	1.3533 (16)	C6—H6A	0.9300
N1—H1A	0.8600	C2—C1	1.489 (2)
O2—C3	1.2026 (15)	C2—H2B	0.9700
O3—C9	1.3611 (17)	C2—H2C	0.9700
O3—C11	1.4299 (17)	C7—H7A	0.9300
C10—C5	1.3988 (18)	C12—H12A	0.9600
C10—C9	1.4095 (18)	C12—H12B	0.9600
C4—C5	1.4508 (18)	C12—H12C	0.9600
C4—H4B	0.9300	C1—H1B	0.9600
C5—C6	1.3998 (18)	C1—H1C	0.9600
C8—C9	1.3783 (19)	C1—H1D	0.9600
C3—O1—C2	116.95 (10)	O3—C11—H11B	110.3
C4—N2—N1	116.81 (10)	C12—C11—H11B	110.3
C10—O4—H4A	109.5	H11A—C11—H11B	108.5
C3—N1—N2	118.90 (10)	C7—C6—C5	120.62 (13)
C3—N1—H1A	120.5	C7—C6—H6A	119.7
N2—N1—H1A	120.5	C5—C6—H6A	119.7
O2—C3—O1	125.97 (12)	O1—C2—C1	112.09 (13)
O2—C3—N1	125.72 (12)	O1—C2—H2B	109.2
O1—C3—N1	108.29 (10)	C1—C2—H2B	109.2
C9—O3—C11	117.30 (12)	O1—C2—H2C	109.2
O4—C10—C5	123.22 (11)	C1—C2—H2C	109.2
O4—C10—C9	116.66 (11)	H2B—C2—H2C	107.9
C5—C10—C9	120.12 (11)	C6—C7—C8	120.42 (13)
N2—C4—C5	121.33 (11)	C6—C7—H7A	119.8
N2—C4—H4B	119.3	C8—C7—H7A	119.8
C5—C4—H4B	119.3	C11—C12—H12A	109.5
C10—C5—C6	119.00 (12)	C11—C12—H12B	109.5
C10—C5—C4	121.56 (11)	H12A—C12—H12B	109.5
C6—C5—C4	119.44 (12)	C11—C12—H12C	109.5
C9—C8—C7	120.52 (13)	H12A—C12—H12C	109.5
C9—C8—H8A	119.7	H12B—C12—H12C	109.5
C7—C8—H8A	119.7	C2—C1—H1B	109.5
O3—C9—C8	125.71 (12)	C2—C1—H1C	109.5
O3—C9—C10	114.97 (12)	H1B—C1—H1C	109.5
C8—C9—C10	119.32 (12)	C2—C1—H1D	109.5
O3—C11—C12	107.13 (14)	H1B—C1—H1D	109.5
O3—C11—H11A	110.3	H1C—C1—H1D	109.5
C12—C11—H11A	110.3

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O4—H4A···N2	0.82	1.91	2.6290 (15)	145
N1—H1A···O2^i	0.86	2.31	2.9633 (15)	132

Symmetry code: (i) −x+1, y+1/2, −z+1/2.