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The pyran ring of the title mol­ecule, C23H21NO3, adopts a flattened boat conformation. In the crystal structure, the amino group is involved in both intra- and intermolecular N—H...O hydrogen bonds. The mol­ecules form centrosymmetric dimers which are interlinked by weak C—H...π interactions.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536803017033/ci6251sup1.cif
Contains datablocks global, I

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S1600536803017033/ci6251Isup2.hkl
Contains datablock I

CCDC reference: 222849

Key indicators

  • Single-crystal X-ray study
  • T = 292 K
  • Mean [sigma](C-C) = 0.003 Å
  • R factor = 0.041
  • wR factor = 0.117
  • Data-to-parameter ratio = 12.8

checkCIF/PLATON results

No syntax errors found



Alert level C PLAT242_ALERT_2_C Check Low U(eq) as Compared to Neighbors .. C20
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 1 ALERT level C = Check and explain 0 ALERT level G = General alerts; check 0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 1 ALERT type 2 Indicator that the structure model may be wrong or deficient 0 ALERT type 3 Indicator that the structure quality may be low 0 ALERT type 4 Improvement, methodology, query or suggestion

Comment top

4H-Chromene is a structural unit of some natural products. 4H-Chromenes with amino and cyano groups are also the synthons of some special natural products (Hatokeyama et al., 1998; Ocallaghan & McMurry, 1995). We have previously reported the synthesis of some 4H-chromene derivatives (Shi et al., 2002; Zhuang et al., 2002). We report here the X-ray crystal structure of the title compound, (I).

The bond lengths and angles in (I) show normal values (Table 1). In the title molecule, the naphthalene ring system is planar within ±0.014 (3) Å. The pyran ring adopts a flattened boat conformation, with atoms O1 and C3 deviating from the C1/C2/C4/C5 plane by 0.143 (1) and 0.299 (2) Å, respectively. The naphthalene and phenyl ring planes form dihedral angles of 7.60 (5) and 89.16 (6)°, respectively, with the C1/C2/C4/C5 plane. The sum of the bond angles [353.0 (2)°] around N indiactes a planar geometry. An intramolecular N—H1A···O3 hydrogen bond is formed between the amino N atom and O atom of the carbonyl group (Table 2). The other H atom of the amino group is involved in weak N—H1B···O3(-x, −y, 1 − z) interactions to form centrosymmetric dimers (Fig. 2). The dimers are interlinked by weak C—H···π interactions involving the symmetry-related phenyl rings.

Experimental top

The title compound was prepared by the reaction of 2-naphthol with 4-methylbenzaldehyde and ethyl cyanoactate in ethanol in the presence of piperidine as catalyst. Single crystals suitable for X-ray diffraction were obtained by slow evaporation from an N,N-dimethylformamide–water solution.

Refinement top

The C bound H atoms were fixed geometrically and were treated as riding on their parent C atoms, with C—H distances in the range 0.93–0.97 Å; the Uiso(H) values were set equal to 1.5Ueq(C) for the methyl H atoms and 1.2Ueq(C) for the aromatic and methylene H atoms. The amino H atoms, H1A and H1B, were located from a difference Fourier map and their positional and isotropic displacement parameters were refined with N—H distances restrained to be 0.86 (1) Å.

Computing details top

Data collection: XSCANS (Siemens, 1994); cell refinement: XSCANS; data reduction: SHELXTL (Sheldrick, 1997); program(s) used to solve structure: SHELXTL; program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Figures top
[Figure 1] Fig. 1. The structure of the title compound, showing 50% probability of displacement ellipsoids and the atom-numbering scheme.
[Figure 2] Fig. 2. A view of the molecular packing down the c axis.
Ethyl 2-amino-4-(4-methylphenyl)-4H-benzo[f]chromene-3-carboxylate top
Crystal data top
C23H21NO3Z = 2
Mr = 359.41F(000) = 380
Triclinic, P1Dx = 1.284 Mg m3
Hall symbol: -P 1Melting point: 474-475 K K
a = 9.394 (2) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.396 (1) ÅCell parameters from 31 reflections
c = 11.005 (2) Åθ = 3.7–14.3°
α = 94.98 (1)°µ = 0.09 mm1
β = 98.30 (1)°T = 292 K
γ = 102.95 (1)°Block, colorless
V = 929.6 (3) Å30.56 × 0.50 × 0.36 mm
Data collection top
Siemens P4
diffractometer
Rint = 0.012
Radiation source: normal-focus sealed tubeθmax = 25.0°, θmin = 1.9°
Graphite monochromatorh = 011
ω scansk = 1110
3602 measured reflectionsl = 1312
3264 independent reflections3 standard reflections every 97 reflections
2205 reflections with I > 2σ(I) intensity decay: 3.0%
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.041H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.117 w = 1/[σ2(Fo2) + (0.064P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.01(Δ/σ)max < 0.001
3264 reflectionsΔρmax = 0.16 e Å3
255 parametersΔρmin = 0.15 e Å3
2 restraintsExtinction correction: SHELXTL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.029 (4)
Crystal data top
C23H21NO3γ = 102.95 (1)°
Mr = 359.41V = 929.6 (3) Å3
Triclinic, P1Z = 2
a = 9.394 (2) ÅMo Kα radiation
b = 9.396 (1) ŵ = 0.09 mm1
c = 11.005 (2) ÅT = 292 K
α = 94.98 (1)°0.56 × 0.50 × 0.36 mm
β = 98.30 (1)°
Data collection top
Siemens P4
diffractometer
Rint = 0.012
3602 measured reflections3 standard reflections every 97 reflections
3264 independent reflections intensity decay: 3.0%
2205 reflections with I > 2σ(I)
Refinement top
R[F2 > 2σ(F2)] = 0.0412 restraints
wR(F2) = 0.117H atoms treated by a mixture of independent and constrained refinement
S = 1.01Δρmax = 0.16 e Å3
3264 reflectionsΔρmin = 0.15 e Å3
255 parameters
Special details top

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 (Å2) top
xyzUiso*/Ueq
O10.13586 (14)0.41521 (13)0.47413 (11)0.0584 (4)
O20.30717 (14)0.20685 (12)0.82157 (12)0.0581 (4)
O30.10953 (15)0.06869 (13)0.69058 (13)0.0686 (4)
N0.00388 (19)0.1946 (2)0.4971 (2)0.0658 (5)
C10.12097 (18)0.30647 (18)0.54773 (17)0.0476 (4)
C20.21166 (18)0.31503 (17)0.65719 (15)0.0432 (4)
C30.31937 (17)0.45914 (16)0.71206 (14)0.0402 (4)
H30.41060.43730.75260.048*
C40.35729 (18)0.55277 (17)0.61128 (15)0.0420 (4)
C50.26502 (19)0.52851 (18)0.50094 (16)0.0488 (4)
C60.2873 (2)0.6147 (2)0.40432 (18)0.0651 (5)
H60.22120.59300.33000.078*
C70.4071 (3)0.7300 (2)0.42154 (19)0.0693 (6)
H70.42210.78870.35850.083*
C80.5094 (2)0.76279 (19)0.53287 (18)0.0566 (5)
C90.6352 (3)0.8834 (2)0.5525 (2)0.0743 (6)
H90.65130.94300.49030.089*
C100.7318 (3)0.9131 (2)0.6598 (3)0.0810 (7)
H100.81280.99360.67140.097*
C110.7109 (2)0.8234 (2)0.7538 (2)0.0698 (6)
H110.77940.84360.82680.084*
C120.59049 (19)0.70610 (19)0.73956 (18)0.0563 (5)
H120.57750.64800.80330.068*
C130.48582 (18)0.67258 (17)0.62886 (16)0.0462 (4)
C140.2013 (2)0.18703 (18)0.72085 (17)0.0491 (4)
C150.3120 (2)0.0805 (2)0.88819 (19)0.0688 (6)
H15A0.21170.02410.88750.083*
H15B0.35780.11430.97370.083*
C160.3969 (3)0.0152 (2)0.8315 (2)0.0857 (7)
H16A0.35120.04930.74710.103*
H16B0.39760.09800.87670.103*
H16C0.49680.03990.83400.103*
C170.25595 (17)0.54075 (16)0.80972 (14)0.0390 (4)
C180.3136 (2)0.5597 (2)0.93329 (17)0.0649 (6)
H180.39650.52470.95950.078*
C190.2512 (3)0.6299 (2)1.02001 (18)0.0753 (6)
H190.29330.64091.10310.090*
C200.1293 (2)0.68350 (19)0.98655 (18)0.0602 (5)
C210.0721 (2)0.6643 (2)0.86325 (19)0.0640 (5)
H210.01090.69940.83730.077*
C220.1335 (2)0.59448 (19)0.77602 (16)0.0546 (5)
H220.09120.58360.69290.065*
C230.0588 (3)0.7582 (2)1.0807 (2)0.0945 (8)
H23A0.04640.85081.05600.113*
H23B0.12130.77461.16020.113*
H23C0.03620.69671.08570.113*
H1A0.003 (3)0.119 (2)0.540 (2)0.126 (11)*
H1B0.021 (2)0.193 (2)0.4187 (10)0.077 (7)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0560 (8)0.0594 (8)0.0549 (8)0.0123 (7)0.0018 (6)0.0030 (6)
O20.0691 (9)0.0427 (7)0.0640 (8)0.0158 (6)0.0091 (7)0.0118 (6)
O30.0687 (9)0.0417 (7)0.0898 (10)0.0002 (7)0.0187 (8)0.0030 (7)
N0.0537 (11)0.0624 (12)0.0700 (13)0.0056 (9)0.0009 (9)0.0129 (11)
C10.0443 (10)0.0424 (10)0.0556 (11)0.0130 (8)0.0082 (9)0.0043 (8)
C20.0420 (9)0.0380 (9)0.0505 (10)0.0122 (7)0.0099 (8)0.0004 (7)
C30.0368 (9)0.0390 (9)0.0456 (9)0.0121 (7)0.0056 (7)0.0041 (7)
C40.0436 (9)0.0395 (9)0.0473 (10)0.0154 (8)0.0143 (8)0.0039 (7)
C50.0533 (11)0.0462 (10)0.0499 (10)0.0174 (9)0.0108 (9)0.0043 (8)
C60.0845 (15)0.0676 (13)0.0503 (11)0.0286 (12)0.0144 (10)0.0132 (10)
C70.0984 (17)0.0594 (13)0.0650 (14)0.0288 (13)0.0376 (13)0.0223 (10)
C80.0683 (13)0.0455 (10)0.0660 (13)0.0186 (9)0.0360 (11)0.0079 (9)
C90.0892 (17)0.0521 (12)0.0886 (16)0.0083 (12)0.0530 (14)0.0065 (11)
C100.0686 (15)0.0584 (13)0.113 (2)0.0067 (11)0.0529 (15)0.0104 (14)
C110.0477 (12)0.0664 (13)0.0884 (15)0.0033 (10)0.0202 (11)0.0151 (12)
C120.0468 (11)0.0510 (11)0.0709 (13)0.0096 (9)0.0175 (10)0.0008 (9)
C130.0460 (10)0.0395 (9)0.0577 (11)0.0152 (8)0.0199 (9)0.0006 (8)
C140.0504 (11)0.0393 (10)0.0604 (12)0.0114 (9)0.0212 (9)0.0001 (8)
C150.0886 (16)0.0563 (12)0.0720 (14)0.0251 (11)0.0255 (12)0.0258 (10)
C160.1012 (18)0.0667 (14)0.1074 (19)0.0416 (14)0.0318 (15)0.0299 (13)
C170.0393 (9)0.0346 (8)0.0414 (9)0.0068 (7)0.0052 (7)0.0039 (7)
C180.0636 (12)0.0867 (15)0.0485 (11)0.0329 (11)0.0013 (9)0.0047 (10)
C190.0888 (16)0.0941 (16)0.0400 (11)0.0218 (14)0.0081 (11)0.0033 (10)
C200.0733 (14)0.0473 (11)0.0595 (13)0.0074 (10)0.0261 (11)0.0026 (9)
C210.0649 (13)0.0682 (13)0.0689 (13)0.0340 (11)0.0176 (10)0.0045 (10)
C220.0579 (11)0.0622 (12)0.0479 (11)0.0271 (10)0.0066 (9)0.0007 (9)
C230.120 (2)0.0806 (16)0.0892 (17)0.0223 (15)0.0543 (15)0.0126 (13)
Geometric parameters (Å, º) top
O1—C11.353 (2)C10—H100.93
O1—C51.399 (2)C11—C121.371 (2)
O2—C141.347 (2)C11—H110.93
O2—C151.454 (2)C12—C131.414 (2)
O3—C141.2305 (19)C12—H120.93
N—C11.352 (2)C15—C161.484 (3)
N—H1A0.88 (1)C15—H15A0.97
N—H1B0.86 (1)C15—H15B0.97
C1—C21.356 (2)C16—H16A0.96
C2—C141.435 (2)C16—H16B0.96
C2—C31.513 (2)C16—H16C0.96
C3—C41.508 (2)C17—C181.370 (2)
C3—C171.531 (2)C17—C221.373 (2)
C3—H30.98C18—C191.383 (3)
C4—C51.355 (2)C18—H180.93
C4—C131.431 (2)C19—C201.367 (3)
C5—C61.403 (3)C19—H190.93
C6—C71.354 (3)C20—C211.366 (3)
C6—H60.93C20—C231.512 (2)
C7—C81.408 (3)C21—C221.380 (2)
C7—H70.93C21—H210.93
C8—C91.418 (3)C22—H220.93
C8—C131.422 (2)C23—H23A0.96
C9—C101.348 (3)C23—H23B0.96
C9—H90.93C23—H23C0.96
C10—C111.398 (3)
C1—O1—C5118.11 (13)C11—C12—H12119.7
C14—O2—C15116.99 (14)C13—C12—H12119.7
C1—N—H1A111.7 (19)C12—C13—C8118.33 (17)
C1—N—H1B113.3 (15)C12—C13—C4122.26 (16)
H1A—N—H1B128 (2)C8—C13—C4119.40 (17)
N—C1—O1110.26 (17)O3—C14—O2120.93 (17)
N—C1—C2126.81 (19)O3—C14—C2126.33 (18)
O1—C1—C2122.93 (15)O2—C14—C2112.74 (15)
C1—C2—C14119.12 (16)O2—C15—C16111.19 (16)
C1—C2—C3119.98 (15)O2—C15—H15A109.4
C14—C2—C3120.88 (15)C16—C15—H15A109.4
C4—C3—C2110.25 (13)O2—C15—H15B109.4
C4—C3—C17111.12 (12)C16—C15—H15B109.4
C2—C3—C17110.72 (13)H15A—C15—H15B108.0
C4—C3—H3108.2C15—C16—H16A109.5
C2—C3—H3108.2C15—C16—H16B109.5
C17—C3—H3108.2C15—C16—H16C109.5
C5—C4—C13117.62 (16)C18—C17—C22116.92 (16)
C5—C4—C3119.96 (15)C18—C17—C3122.67 (15)
C13—C4—C3122.36 (15)C22—C17—C3120.37 (14)
C4—C5—O1122.42 (16)C17—C18—C19121.47 (18)
C4—C5—C6123.92 (18)C17—C18—H18119.3
O1—C5—C6113.65 (16)C19—C18—H18119.3
C7—C6—C5118.63 (19)C20—C19—C18121.67 (19)
C7—C6—H6120.7C20—C19—H19119.2
C5—C6—H6120.7C18—C19—H19119.2
C6—C7—C8121.34 (19)C21—C20—C19116.70 (18)
C6—C7—H7119.3C21—C20—C23121.2 (2)
C8—C7—H7119.3C19—C20—C23122.1 (2)
C7—C8—C9122.0 (2)C20—C21—C22122.09 (18)
C7—C8—C13119.05 (17)C20—C21—H21119.0
C9—C8—C13118.9 (2)C22—C21—H21119.0
C10—C9—C8121.2 (2)C17—C22—C21121.17 (17)
C10—C9—H9119.4C17—C22—H22119.4
C8—C9—H9119.4C21—C22—H22119.4
C9—C10—C11120.3 (2)C20—C23—H23A109.5
C9—C10—H10119.8C20—C23—H23B109.5
C11—C10—H10119.8H23A—C23—H23B109.5
C12—C11—C10120.7 (2)C20—C23—H23C109.5
C12—C11—H11119.6H23A—C23—H23C109.5
C10—C11—H11119.6H23B—C23—H23C109.5
C11—C12—C13120.6 (2)
C5—O1—C1—N169.46 (14)C11—C12—C13—C4178.81 (15)
C5—O1—C1—C211.8 (2)C7—C8—C13—C12179.31 (16)
N—C1—C2—C1410.1 (3)C9—C8—C13—C120.9 (2)
O1—C1—C2—C14171.32 (15)C7—C8—C13—C41.4 (2)
N—C1—C2—C3168.46 (16)C9—C8—C13—C4178.45 (15)
O1—C1—C2—C310.1 (2)C5—C4—C13—C12178.98 (15)
C1—C2—C3—C425.5 (2)C3—C4—C13—C123.7 (2)
C14—C2—C3—C4155.90 (14)C5—C4—C13—C81.7 (2)
C1—C2—C3—C1797.84 (17)C3—C4—C13—C8175.62 (14)
C14—C2—C3—C1780.72 (18)C15—O2—C14—O33.0 (2)
C2—C3—C4—C521.5 (2)C15—O2—C14—C2176.27 (14)
C17—C3—C4—C5101.67 (17)C1—C2—C14—O35.4 (3)
C2—C3—C4—C13161.22 (13)C3—C2—C14—O3173.17 (15)
C17—C3—C4—C1375.62 (18)C1—C2—C14—O2173.86 (14)
C13—C4—C5—O1179.57 (13)C3—C2—C14—O27.6 (2)
C3—C4—C5—O12.1 (2)C14—O2—C15—C1684.2 (2)
C13—C4—C5—C60.8 (2)C4—C3—C17—C18125.74 (18)
C3—C4—C5—C6176.62 (15)C2—C3—C17—C18111.38 (18)
C1—O1—C5—C416.0 (2)C4—C3—C17—C2256.43 (19)
C1—O1—C5—C6165.14 (15)C2—C3—C17—C2266.45 (19)
C4—C5—C6—C70.6 (3)C22—C17—C18—C190.0 (3)
O1—C5—C6—C7178.31 (16)C3—C17—C18—C19177.93 (18)
C5—C6—C7—C81.0 (3)C17—C18—C19—C200.0 (3)
C6—C7—C8—C9179.81 (17)C18—C19—C20—C210.0 (3)
C6—C7—C8—C130.0 (3)C18—C19—C20—C23179.01 (19)
C7—C8—C9—C10179.94 (19)C19—C20—C21—C220.0 (3)
C13—C8—C9—C100.1 (3)C23—C20—C21—C22179.03 (18)
C8—C9—C10—C111.0 (3)C18—C17—C22—C210.0 (3)
C9—C10—C11—C121.4 (3)C3—C17—C22—C21177.98 (16)
C10—C11—C12—C130.7 (3)C20—C21—C22—C170.0 (3)
C11—C12—C13—C80.5 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N—H1A···O30.88 (1)1.98 (2)2.697 (3)137 (2)
N—H1B···O3i0.86 (1)2.54 (2)2.969 (2)112 (1)
C16—H16B···CgPii0.963.013.785 (2)138
C23—H23C···CgPiii0.962.983.789 (2)143
Symmetry codes: (i) x, y, z+1; (ii) x, y1, z; (iii) x, y+1, z+2.

Experimental details

Crystal data
Chemical formulaC23H21NO3
Mr359.41
Crystal system, space groupTriclinic, P1
Temperature (K)292
a, b, c (Å)9.394 (2), 9.396 (1), 11.005 (2)
α, β, γ (°)94.98 (1), 98.30 (1), 102.95 (1)
V3)929.6 (3)
Z2
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.56 × 0.50 × 0.36
Data collection
DiffractometerSiemens P4
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
3602, 3264, 2205
Rint0.012
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.041, 0.117, 1.01
No. of reflections3264
No. of parameters255
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.16, 0.15

Computer programs: XSCANS (Siemens, 1994), XSCANS, SHELXTL (Sheldrick, 1997), SHELXTL.

Selected geometric parameters (Å, º) top
O1—C11.353 (2)N—C11.352 (2)
O1—C51.399 (2)C1—C21.356 (2)
O2—C141.347 (2)C2—C31.513 (2)
O2—C151.454 (2)C3—C41.508 (2)
O3—C141.2305 (19)
N—C1—O1110.26 (17)C4—C3—C17111.12 (12)
N—C1—C2126.81 (19)C2—C3—C17110.72 (13)
C4—C3—C2110.25 (13)O3—C14—C2126.33 (18)
C14—C2—C3—C1780.72 (18)C1—C2—C14—O35.4 (3)
C17—C3—C4—C1375.62 (18)C3—C2—C14—O27.6 (2)
C15—O2—C14—O33.0 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N—H1A···O30.88 (1)1.98 (2)2.697 (3)137 (2)
N—H1B···O3i0.86 (1)2.54 (2)2.969 (2)112 (1)
C16—H16B···CgPii0.963.013.785 (2)138
C23—H23C···CgPiii0.962.983.789 (2)143
Symmetry codes: (i) x, y, z+1; (ii) x, y1, z; (iii) x, y+1, z+2.
 

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