N′-[(1E)-(4-Fluoro­phen­yl)methyl­ene]-6-meth­oxy-2-naphthohydrazide

The title compound, C₁₉H₁₅FN₂O₂, is a Schiff base which has been synthesized by a condensation reaction of 6-meth­oxy-2-naphthohydrazide and 4-fluoro­benzaldehyde. The mol­ecule is almost planar with the C=N double bond in a trans configuration. The crystal packing is stabilized by N—H...O hydrogen bonds that link mol­ecules into chains running along the c axis. There are also weak C—H...O hydrogen bonds as well as C—H...π-ring inter­actions in the crystal structure.

Key indicators

• Single-crystal X-ray study
• T = 173 K
• Mean [sigma](C-C) = 0.007 Å
• R factor = 0.063
• wR factor = 0.127
• Data-to-parameter ratio = 7.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax .LT. 18) .....       7.06
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          7

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           25.88
           From the CIF: _reflns_number_total               1531
           Count of symmetry unique reflns         1544
           Completeness (_total/calc)             99.16%
           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
   0 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
   2 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

The title compound, C₁₉H₁₅FN₂O₂, is a Schiff base which has been synthesized by a condensation reaction of 6-methoxy-2-naphthohydrazide and 4-fluorobenzaldehyde.

A view of (I) is shown in Fig. 1. Bond lengths and angles can be regarded as normal (Cambridge Crystallographic Database, Version 5.28, November 2006; updated January 2007 (Allen, 2002); Mogul Version 1.1 (Bruno et al., 2004). The molecule is almost planar (r.m.s. deviation for all non-H atoms = 0.123 Å) with the C=N double bond in a trans configuration. The crystal packing is stabilized by N—H···O hydrogen bonds that link molecules into chains running along the c axis (Tab. 1 and Fig. 2). There are also C—H···O weak hydrogen bonds (Tab. 1) as well as C—H···π-ring interactions in the structure (Tab. 2).

Related literature

Some related structures of hydrazides such as 2'-(4-dimethylaminobenzylidene)pyrazine-2-carbohydrazide (Shi & Yuan, 2006), N'-(3-ethoxy-4-hydroxybenzylidene)isonicotino-hydrazide (Qian et al., 2006) and 2'-(1,3-benzodioxol-5-yl-methylene)-2-methoxybenzo-hydrazide (Jing & Yu, 2007) and a Schiff base (Yathirajan et al., 2007) have been reported. For related literature, see: Allen (2002); Bruno et al. (2004).

S2. Experimental

A mixture of 6-methoxy-2-naphthohydrazide (1.08 g, 0.005 mol) and 4-fluorobenzaldehyde (0.62 ml, 0.005 mol) in 15 ml of absolute ethanol containing 2 drops of 4 M sulfuric acid was refluxed for about 3 h. On cooling to room temperature, a solid precipitated. The solid was filtered off, redissolved in 10 ml of a mixture (1:1) of dimethylformamide and acetone, and then recrystallized. (M. p.: 492–494 K). Analysis for C₁₉H₁₅FN₂O₂: Found (Calculated): C: 70.68 (70.80); H: 4.63 (4.69); N: 8.62 (8.69) weight %.

S3. Refinement

All the H atoms were found in a difference Fourier map. Nevertheless, the H atoms were refined using a riding model with N—H = 0.88 Å, C—H = 0.95Å or C_methyl—H = 0.96Å and U_iso(H) = 1.2U_eq(C,N) or U_iso(H) = 1.5U_eq(C_methyl). In the absence of anomalous scatterers 1517 Friedel pairs have been merged prior to refinement.

Computing details

Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003) and XP in SHELXTL-Plus (Sheldrick, 1991); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. A view of the title compound with the atom numbering. The displacement ellipsoids are at the 50% probability level.
	Fig. 2. Packing diagram of the title compound. H atoms bonded to C are not shown. The N—H···O hydrogen bonds are shown as dashed lines.

N'-[(1E)-(4-Fluorophenyl)methylene]-6-methoxy-2-naphthohydrazide

Crystal data

C19H15FN2O2	F(000) = 336
Mr = 322.33	Dx = 1.345 Mg m^−3
Monoclinic, Pc	Melting point = 492–494 K
Hall symbol: P -2yc	Mo Kα radiation, λ = 0.71073 Å
a = 15.681 (2) Å	Cell parameters from 6963 reflections
b = 5.6574 (7) Å	θ = 3.7–25.3°
c = 9.2758 (10) Å	µ = 0.10 mm^−1
β = 104.746 (9)°	T = 173 K
V = 795.79 (17) Å^3	Needle, colourless
Z = 2	0.24 × 0.09 × 0.08 mm

Data collection

Stoe IPDSII two-circle diffractometer	1246 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.069
Graphite monochromator	θmax = 25.9°, θmin = 3.6°
ω scans	h = −19→19
9090 measured reflections	k = −6→6
1531 independent reflections	l = −11→11

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)] = 0.063	Hydrogen site location: difference Fourier map
wR(F^2) = 0.127	H-atom parameters constrained
S = 1.57	w = 1/[σ^2(Fo^2) + (0.0088P)^2] where P = (Fo^2 + 2Fc^2)/3
1531 reflections	(Δ/σ)max < 0.001
217 parameters	Δρmax = 0.23 e Å^−3
2 restraints	Δρmin = −0.25 e Å^−3
60 constraints

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
F1	0.3049 (2)	−0.5672 (6)	0.2289 (4)	0.0710 (10)
N1	0.6850 (2)	0.3354 (7)	0.3540 (4)	0.0459 (10)
H1	0.7100	0.3124	0.2803	0.055*
N2	0.6140 (2)	0.1982 (8)	0.3648 (4)	0.0454 (10)
O1	0.6834 (2)	0.5483 (7)	0.5623 (3)	0.0560 (10)
O2	1.1811 (2)	0.9463 (7)	0.3792 (4)	0.0596 (10)
C1	0.7163 (3)	0.5057 (9)	0.4572 (4)	0.0451 (12)
C2	0.5913 (3)	0.0397 (9)	0.2636 (5)	0.0443 (11)
H2	0.6241	0.0238	0.1909	0.053*
C3	1.2147 (4)	1.1340 (11)	0.4833 (7)	0.0630 (15)
H3A	1.1768	1.2735	0.4573	0.095*
H3B	1.2748	1.1740	0.4791	0.095*
H3C	1.2152	1.0822	0.5844	0.095*
C11	0.7977 (3)	0.6295 (9)	0.4426 (4)	0.0417 (11)
C12	0.8549 (3)	0.5335 (9)	0.3667 (5)	0.0426 (11)
H12	0.8393	0.3898	0.3136	0.051*
C13	0.9355 (3)	0.6423 (9)	0.3658 (5)	0.0402 (11)
C14	0.9964 (3)	0.5461 (9)	0.2891 (5)	0.0446 (11)
H14	0.9813	0.4052	0.2327	0.054*
C15	1.0744 (3)	0.6503 (9)	0.2950 (5)	0.0478 (12)
H15	1.1129	0.5842	0.2416	0.057*
C16	1.0994 (3)	0.8597 (9)	0.3811 (5)	0.0451 (12)
C17	1.0422 (3)	0.9647 (9)	0.4528 (5)	0.0467 (12)
H17	1.0585	1.1073	0.5068	0.056*
C18	0.9591 (3)	0.8602 (8)	0.4460 (5)	0.0408 (11)
C19	0.8981 (3)	0.9577 (9)	0.5207 (5)	0.0442 (11)
H19	0.9120	1.1021	0.5737	0.053*
C20	0.8208 (3)	0.8489 (9)	0.5175 (5)	0.0454 (12)
H20	0.7811	0.9205	0.5665	0.055*
C21	0.5165 (3)	−0.1173 (8)	0.2571 (4)	0.0415 (11)
C22	0.4518 (3)	−0.0650 (10)	0.3318 (5)	0.0470 (12)
H22	0.4567	0.0750	0.3899	0.056*
C23	0.3808 (3)	−0.2141 (10)	0.3223 (5)	0.0528 (13)
H23	0.3366	−0.1758	0.3719	0.063*
C24	0.3750 (3)	−0.4206 (10)	0.2395 (6)	0.0517 (13)
C25	0.4372 (3)	−0.4777 (10)	0.1636 (5)	0.0508 (12)
H25	0.4319	−0.6195	0.1071	0.061*
C26	0.5081 (3)	−0.3244 (9)	0.1707 (5)	0.0484 (12)
H26	0.5506	−0.3602	0.1170	0.058*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
F1	0.065 (2)	0.074 (2)	0.079 (2)	−0.0181 (16)	0.0265 (17)	−0.0044 (18)
N1	0.043 (2)	0.071 (3)	0.030 (2)	−0.009 (2)	0.0204 (17)	−0.0011 (18)
N2	0.045 (2)	0.063 (3)	0.0297 (18)	0.0003 (18)	0.0123 (16)	0.0062 (18)
O1	0.060 (2)	0.083 (3)	0.0327 (17)	−0.0114 (18)	0.0258 (15)	−0.0084 (16)
O2	0.048 (2)	0.082 (3)	0.055 (2)	−0.0157 (19)	0.0231 (17)	−0.0125 (19)
C1	0.053 (3)	0.057 (3)	0.028 (2)	0.003 (2)	0.015 (2)	0.004 (2)
C2	0.036 (3)	0.069 (3)	0.031 (2)	0.002 (2)	0.0141 (19)	0.003 (2)
C3	0.058 (3)	0.074 (4)	0.059 (3)	−0.017 (3)	0.018 (3)	−0.013 (3)
C11	0.041 (3)	0.057 (3)	0.030 (2)	0.002 (2)	0.0143 (19)	0.004 (2)
C12	0.045 (3)	0.060 (3)	0.025 (2)	0.000 (2)	0.0127 (19)	0.004 (2)
C13	0.039 (3)	0.055 (3)	0.028 (2)	0.001 (2)	0.0111 (18)	0.002 (2)
C14	0.042 (3)	0.061 (3)	0.035 (2)	0.000 (2)	0.017 (2)	−0.004 (2)
C15	0.044 (3)	0.066 (3)	0.037 (3)	0.005 (3)	0.017 (2)	0.000 (2)
C16	0.043 (3)	0.061 (3)	0.033 (2)	−0.002 (2)	0.012 (2)	0.004 (2)
C17	0.056 (3)	0.050 (3)	0.036 (2)	−0.006 (2)	0.014 (2)	−0.005 (2)
C18	0.042 (3)	0.051 (3)	0.033 (2)	−0.002 (2)	0.0151 (19)	0.005 (2)
C19	0.051 (3)	0.052 (3)	0.033 (2)	0.000 (2)	0.018 (2)	−0.001 (2)
C20	0.049 (3)	0.060 (3)	0.030 (2)	0.007 (2)	0.015 (2)	0.007 (2)
C21	0.035 (2)	0.064 (3)	0.026 (2)	0.008 (2)	0.0078 (18)	0.006 (2)
C22	0.044 (3)	0.066 (3)	0.033 (2)	0.002 (2)	0.015 (2)	−0.001 (2)
C23	0.039 (3)	0.073 (4)	0.051 (3)	0.007 (2)	0.022 (2)	0.011 (3)
C24	0.038 (3)	0.068 (4)	0.049 (3)	−0.003 (3)	0.011 (2)	0.009 (3)
C25	0.051 (3)	0.059 (3)	0.042 (3)	0.002 (2)	0.011 (2)	0.000 (2)
C26	0.044 (3)	0.064 (3)	0.038 (2)	0.009 (2)	0.014 (2)	0.006 (2)

Geometric parameters (Å, º)

F1—C24	1.360 (6)	C14—H14	0.9500
N1—C1	1.359 (6)	C15—C16	1.427 (7)
N1—N2	1.381 (5)	C15—H15	0.9500
N1—H1	0.8800	C16—C17	1.379 (7)
N2—C2	1.281 (6)	C17—C18	1.417 (7)
O1—C1	1.238 (5)	C17—H17	0.9500
O2—C16	1.377 (6)	C18—C19	1.428 (6)
O2—C3	1.442 (7)	C19—C20	1.353 (7)
C1—C11	1.492 (7)	C19—H19	0.9500
C2—C21	1.460 (7)	C20—H20	0.9500
C2—H2	0.9500	C21—C22	1.399 (6)
C3—H3A	0.9800	C21—C26	1.407 (7)
C3—H3B	0.9800	C22—C23	1.381 (8)
C3—H3C	0.9800	C22—H22	0.9500
C11—C12	1.384 (6)	C23—C24	1.389 (7)
C11—C20	1.424 (7)	C23—H23	0.9500
C12—C13	1.408 (7)	C24—C25	1.378 (7)
C12—H12	0.9500	C25—C26	1.399 (8)
C13—C14	1.436 (6)	C25—H25	0.9500
C13—C18	1.439 (6)	C26—H26	0.9500
C14—C15	1.346 (7)
C1—N1—N2	120.1 (3)	O2—C16—C15	114.3 (4)
C1—N1—H1	120.0	C17—C16—C15	120.5 (4)
N2—N1—H1	120.0	C16—C17—C18	120.1 (5)
C2—N2—N1	114.8 (4)	C16—C17—H17	119.9
C16—O2—C3	115.8 (4)	C18—C17—H17	119.9
O1—C1—N1	123.0 (4)	C17—C18—C19	122.6 (5)
O1—C1—C11	121.2 (4)	C17—C18—C13	119.6 (4)
N1—C1—C11	115.7 (4)	C19—C18—C13	117.7 (4)
N2—C2—C21	121.7 (4)	C20—C19—C18	121.4 (5)
N2—C2—H2	119.1	C20—C19—H19	119.3
C21—C2—H2	119.1	C18—C19—H19	119.3
O2—C3—H3A	109.5	C19—C20—C11	121.5 (4)
O2—C3—H3B	109.5	C19—C20—H20	119.3
H3A—C3—H3B	109.5	C11—C20—H20	119.3
O2—C3—H3C	109.5	C22—C21—C26	118.9 (4)
H3A—C3—H3C	109.5	C22—C21—C2	121.9 (4)
H3B—C3—H3C	109.5	C26—C21—C2	119.2 (4)
C12—C11—C20	118.2 (4)	C23—C22—C21	120.9 (5)
C12—C11—C1	122.8 (5)	C23—C22—H22	119.5
C20—C11—C1	118.8 (4)	C21—C22—H22	119.5
C11—C12—C13	122.0 (5)	C22—C23—C24	119.2 (4)
C11—C12—H12	119.0	C22—C23—H23	120.4
C13—C12—H12	119.0	C24—C23—H23	120.4
C12—C13—C14	123.3 (5)	F1—C24—C25	118.9 (5)
C12—C13—C18	119.0 (4)	F1—C24—C23	119.4 (4)
C14—C13—C18	117.7 (4)	C25—C24—C23	121.6 (5)
C15—C14—C13	121.8 (5)	C24—C25—C26	119.2 (5)
C15—C14—H14	119.1	C24—C25—H25	120.4
C13—C14—H14	119.1	C26—C25—H25	120.4
C14—C15—C16	120.2 (4)	C25—C26—C21	120.1 (4)
C14—C15—H15	119.9	C25—C26—H26	120.0
C16—C15—H15	119.9	C21—C26—H26	120.0
O2—C16—C17	125.1 (5)
C1—N1—N2—C2	−178.4 (4)	C16—C17—C18—C13	0.9 (7)
N2—N1—C1—O1	−0.9 (7)	C12—C13—C18—C17	176.5 (5)
N2—N1—C1—C11	175.0 (4)	C14—C13—C18—C17	−3.1 (6)
N1—N2—C2—C21	−178.8 (4)	C12—C13—C18—C19	−1.2 (5)
O1—C1—C11—C12	154.8 (5)	C14—C13—C18—C19	179.2 (5)
N1—C1—C11—C12	−21.2 (7)	C17—C18—C19—C20	−177.1 (4)
O1—C1—C11—C20	−21.0 (7)	C13—C18—C19—C20	0.5 (6)
N1—C1—C11—C20	162.9 (4)	C18—C19—C20—C11	1.5 (7)
C20—C11—C12—C13	2.0 (6)	C12—C11—C20—C19	−2.7 (6)
C1—C11—C12—C13	−173.9 (4)	C1—C11—C20—C19	173.4 (4)
C11—C12—C13—C14	179.5 (4)	N2—C2—C21—C22	17.9 (7)
C11—C12—C13—C18	−0.1 (6)	N2—C2—C21—C26	−163.6 (4)
C12—C13—C14—C15	−177.5 (4)	C26—C21—C22—C23	0.5 (6)
C18—C13—C14—C15	2.1 (7)	C2—C21—C22—C23	179.0 (4)
C13—C14—C15—C16	1.2 (7)	C21—C22—C23—C24	1.2 (7)
C3—O2—C16—C17	12.4 (8)	C22—C23—C24—F1	−179.5 (4)
C3—O2—C16—C15	−170.3 (4)	C22—C23—C24—C25	−1.6 (7)
C14—C15—C16—O2	179.2 (4)	F1—C24—C25—C26	178.2 (4)
C14—C15—C16—C17	−3.5 (7)	C23—C24—C25—C26	0.3 (7)
O2—C16—C17—C18	179.4 (4)	C24—C25—C26—C21	1.4 (7)
C15—C16—C17—C18	2.4 (7)	C22—C21—C26—C25	−1.8 (6)
C16—C17—C18—C19	178.5 (4)	C2—C21—C26—C25	179.7 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1^i	0.88	2.11	2.778 (4)	132
C23—H23···O2^ii	0.95	2.55	3.428 (6)	154
C26—H26···O1^iii	0.95	2.50	3.403 (6)	158
C14—H14···Cg1^i	0.98	2.89	3.666 (5)	140
C19—H19···Cg2^iv	0.93	2.95	3.697 (5)	136

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