3-Amino-1-phenyl-1H-benzo[f]chromene-2-carbonitrile

In the title compound, C₂₀H₁₄N₂O, the phenyl ring is almost normal to the naphthalene ring system with a dihedral angle of 86.72 (9)°. The 4H-pyran ring fused with the naphthalene ring system has a boat conformation. In the crystal, mol­ecules are linked into a helical supra­molecular chain along the b axis via N—H...N hydrogen bonds. The chains are consolidated into a three-dimensional architecture by C—H...π inter­actions.

Key indicators

• Single-crystal X-ray study
• T = 123 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.042
• wR factor = 0.091
• Data-to-parameter ratio = 12.8

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C2     --  C20     ..        5.6 su
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          3
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          3
PLAT915_ALERT_3_C Low Friedel Pair Coverage ......................         53 Perc.

Alert level G
PLAT003_ALERT_2_G Number of Uiso or Uij Restrained Atom Sites ....          6
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF          ?
PLAT371_ALERT_2_G Long   C(sp2)-C(sp1) Bond  C2     -   C20    ...       1.41 Ang.
PLAT791_ALERT_4_G Note: The Model has Chirality at C3     (Verify)          S
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......         49
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600        228

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   4 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   6 ALERT level G = General information/check it is not something unexpected

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   4 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

Chromenes are components of many natural products (Ellis & Lockhart, 2007) and incorporated in numerous medicinal drugs as significant chromophores. They have shown to display anti-viral, anti-tumoral, anti-anaphylactic, spasmolytic, diuretic and clotting activity (Horton et al., 2003). Furthermore, they can be used as photo-active materials, biodegradable agrochemicals and pigments. As a part of our structural investigations on functionalized chromenes and compounds containing the benzopyran fragment, the single-crystal X-ray diffraction study on the title compound was carried out.

In the title compound (I), Fig. 1, the C14–C19 phenyl ring and the C4–C13 naphthalene ring system is essentially planar with the maximum deviations of -0.004 (2) Å for C16 and 0.015 (2) Å for C4, respectively. They make a dihedral angle of 86.72 (9)° with each other.

The 4H-pyran ring (O1/C1–C4/C13) in (I) is puckered with the puckering parameters (Cremer & Pople, 1975) of Q_T = 0.211 (2) Å, θ = 96.2 (5)° and ϕ = 348.9 (6)°. The N1–C1–O1–C13 and N1–C1–C2–C20 torsion angles are -165.54 (17) and -2.6 (3)°, respectively.

In the crystal structure, molecules are linked into a helical supramolecular chain along the b axis via N—H···N hydrogen bonds (Table 1). Three distinct molecules are linked by three such connections involving two acceptors to generate a R³₂(10) ring motif (Fig. 2; Bernstein et al., 1995). Chains are consolidated into a three-dimensional architecture by C—H···π interactions.

Related literature

For biological and industrial applications of chromene compounds, see, for example: Ellis & Lockhart (2007); Horton et al. (2003). For puckering parameters, see: Cremer & Pople (1975). For the graph-set analysis of hydrogen bonding, see: Bernstein et al. (1995).

S2. Experimental

Benzylidenepropanedinitrile (1.54 g; 10 mmol) was dissolved in ethanol (50 ml), followed by addition of naphthalen-2-ol (1.44 g; 10 mmol) and a catalytic amount of TEA. The mixture was stirred and refluxed for 2 h at 350 K. The solid product was deposited on cooling at room temperature and collected by filtration. The crude product was washed by cold ethanol, dried under vacuum and recrystallized from ethanol to give high quality crystals (M.pt: 563 K) suitable for X-ray analysis in an excellent yield (91%).

S3. Refinement

All non-hydrogen atoms were refined with anisotropic thermal parameter, however the carbon atoms of the C14–C19 phenyl ring were refined to approximate isotropic behaviour with the "ISOR and DELU" instruction. The H atoms of the NH₂ group were located by difference synthesis and were refined isotropically. The other H atoms were positioned geometrically, with C—H = 0.95 Å and C—H = 1.00 Å for aromatic and methine H, respectively, and constrained to ride on their parent atoms, with U_iso(H) = 1.2U_eq(C).

Computing details

Data collection: CrysAlis PRO (Oxford Diffraction, 2010); cell refinement: CrysAlis PRO (Oxford Diffraction, 2010); data reduction: CrysAlis PRO (Oxford Diffraction, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Figures

	Fig. 1. The molecular structure of (I), showing the labelling of the non-H atoms and displacement ellipsoids drawn at the 50% probability level.
	Fig. 2. View of the N—H···N hydrogen bonds, having R^32(10) ring motifs, forming chains along the b axis. H atoms not involved in hydrogen bonds have been omitted for clarity.

3-Amino-1-phenyl-1H-benzo[f]chromene-2-carbonitrile

Crystal data

C20H14N2O	F(000) = 312
Mr = 298.33	Dx = 1.349 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 1797 reflections
a = 9.4059 (8) Å	θ = 3.1–28.7°
b = 6.5009 (5) Å	µ = 0.09 mm^−1
c = 12.4919 (10) Å	T = 123 K
β = 105.914 (9)°	Rod, colourless
V = 734.57 (11) Å^3	0.30 × 0.12 × 0.07 mm
Z = 2

Data collection

Oxford Diffraction Xcalibur Eos diffractometer	2780 independent reflections
Radiation source: fine-focus sealed tube	2477 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.019
Detector resolution: 16.0727 pixels mm^-1	θmax = 28.8°, θmin = 3.2°
ω scans	h = −12→10
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010)	k = −7→8
Tmin = 0.955, Tmax = 1.000	l = −16→16
3674 measured reflections

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)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.091	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0342P)^2 + 0.0595P] where P = (Fo^2 + 2Fc^2)/3
2780 reflections	(Δ/σ)max = 0.001
217 parameters	Δρmax = 0.22 e Å^−3
49 restraints	Δρmin = −0.18 e Å^−3

Special details

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement on F² for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The observed criterion of F² > σ(F²) is used only for calculating -R-factor-obs 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	0.91532 (15)	0.1653 (2)	0.28251 (11)	0.0225 (4)
N1	1.0215 (2)	0.2373 (3)	0.14856 (16)	0.0243 (6)
N2	0.9541 (2)	0.7742 (3)	0.08334 (15)	0.0294 (6)
C1	0.9372 (2)	0.3114 (3)	0.21116 (15)	0.0192 (6)
C2	0.8832 (2)	0.5038 (3)	0.21023 (16)	0.0188 (6)
C3	0.7813 (2)	0.5686 (3)	0.28021 (16)	0.0173 (6)
C4	0.7940 (2)	0.4143 (3)	0.37246 (15)	0.0166 (6)
C5	0.7408 (2)	0.4592 (3)	0.46701 (16)	0.0178 (6)
C6	0.6672 (2)	0.6459 (4)	0.47667 (16)	0.0207 (6)
C7	0.6185 (2)	0.6844 (4)	0.56872 (17)	0.0252 (7)
C8	0.6400 (2)	0.5410 (3)	0.65490 (17)	0.0273 (7)
C9	0.7100 (2)	0.3578 (4)	0.64841 (17)	0.0246 (7)
C10	0.7613 (2)	0.3129 (3)	0.55449 (16)	0.0197 (6)
C11	0.8330 (2)	0.1247 (3)	0.54667 (16)	0.0213 (6)
C12	0.8812 (2)	0.0815 (3)	0.45537 (16)	0.0197 (6)
C13	0.8601 (2)	0.2280 (3)	0.37026 (16)	0.0183 (6)
C14	0.6240 (2)	0.6022 (3)	0.20788 (15)	0.0201 (6)
C15	0.5843 (2)	0.7921 (4)	0.15674 (16)	0.0275 (7)
C16	0.4429 (3)	0.8218 (4)	0.08696 (18)	0.0357 (8)
C17	0.3403 (3)	0.6645 (5)	0.06874 (18)	0.0398 (9)
C18	0.3793 (3)	0.4760 (5)	0.11953 (19)	0.0368 (8)
C19	0.5205 (2)	0.4453 (4)	0.18836 (17)	0.0271 (7)
C20	0.9215 (2)	0.6514 (4)	0.13967 (16)	0.0209 (6)
H1N	1.024 (3)	0.297 (4)	0.084 (2)	0.038 (7)*
H2N	1.032 (3)	0.104 (5)	0.146 (2)	0.043 (8)*
H3	0.81820	0.70340	0.31560	0.0210*
H6	0.65140	0.74520	0.41880	0.0250*
H7	0.56950	0.81030	0.57390	0.0300*
H8	0.60620	0.57030	0.71830	0.0330*
H9	0.72390	0.26070	0.70720	0.0290*
H11	0.84780	0.02730	0.60540	0.0260*
H12	0.92820	−0.04580	0.44970	0.0240*
H15	0.65400	0.90140	0.16960	0.0330*
H16	0.41660	0.95100	0.05160	0.0430*
H17	0.24350	0.68570	0.02150	0.0480*
H18	0.30910	0.36740	0.10720	0.0440*
H19	0.54670	0.31510	0.22260	0.0330*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0282 (8)	0.0207 (8)	0.0215 (7)	0.0020 (7)	0.0116 (6)	0.0011 (7)
N1	0.0270 (10)	0.0260 (12)	0.0227 (9)	0.0022 (8)	0.0118 (8)	0.0002 (9)
N2	0.0353 (11)	0.0279 (11)	0.0302 (10)	0.0016 (9)	0.0179 (9)	0.0030 (9)
C1	0.0177 (10)	0.0237 (12)	0.0151 (9)	−0.0048 (9)	0.0028 (8)	−0.0008 (9)
C2	0.0183 (10)	0.0216 (11)	0.0169 (9)	−0.0027 (8)	0.0054 (8)	0.0008 (9)
C3	0.0177 (10)	0.0169 (11)	0.0179 (9)	−0.0023 (8)	0.0059 (7)	−0.0017 (9)
C4	0.0142 (10)	0.0180 (11)	0.0161 (9)	−0.0032 (8)	0.0019 (7)	0.0004 (9)
C5	0.0126 (9)	0.0225 (11)	0.0178 (9)	−0.0037 (8)	0.0034 (8)	0.0000 (9)
C6	0.0187 (10)	0.0226 (11)	0.0209 (9)	−0.0015 (9)	0.0057 (8)	0.0018 (10)
C7	0.0224 (11)	0.0260 (13)	0.0292 (11)	0.0004 (9)	0.0105 (9)	−0.0024 (10)
C8	0.0269 (12)	0.0371 (15)	0.0207 (10)	−0.0030 (10)	0.0114 (9)	−0.0025 (10)
C9	0.0242 (11)	0.0305 (13)	0.0192 (10)	−0.0030 (10)	0.0063 (8)	0.0029 (10)
C10	0.0169 (10)	0.0248 (12)	0.0164 (9)	−0.0023 (9)	0.0030 (8)	0.0003 (9)
C11	0.0218 (11)	0.0224 (12)	0.0178 (10)	−0.0025 (9)	0.0020 (8)	0.0026 (10)
C12	0.0174 (10)	0.0180 (11)	0.0217 (10)	−0.0002 (9)	0.0019 (8)	0.0013 (10)
C13	0.0185 (10)	0.0211 (12)	0.0152 (9)	−0.0033 (8)	0.0047 (8)	−0.0034 (9)
C14	0.0212 (10)	0.0269 (12)	0.0131 (9)	0.0041 (9)	0.0061 (8)	0.0011 (9)
C15	0.0292 (12)	0.0301 (13)	0.0238 (10)	0.0070 (10)	0.0085 (9)	0.0055 (11)
C16	0.0358 (13)	0.0479 (16)	0.0227 (11)	0.0204 (12)	0.0069 (10)	0.0096 (12)
C17	0.0227 (12)	0.073 (2)	0.0219 (11)	0.0134 (13)	0.0033 (9)	0.0024 (14)
C18	0.0208 (11)	0.0592 (17)	0.0291 (12)	−0.0029 (12)	0.0046 (9)	−0.0022 (13)
C19	0.0231 (11)	0.0346 (14)	0.0226 (10)	−0.0019 (10)	0.0044 (9)	−0.0003 (11)
C20	0.0223 (10)	0.0235 (11)	0.0181 (9)	0.0019 (9)	0.0077 (8)	−0.0035 (10)

Geometric parameters (Å, º)

O1—C1	1.356 (2)	C11—C12	1.367 (3)
O1—C13	1.396 (2)	C12—C13	1.400 (3)
N1—C1	1.346 (3)	C14—C19	1.385 (3)
N2—C20	1.160 (3)	C14—C15	1.393 (3)
N1—H1N	0.90 (3)	C15—C16	1.389 (3)
N1—H2N	0.87 (3)	C16—C17	1.381 (4)
C1—C2	1.349 (3)	C17—C18	1.382 (4)
C2—C20	1.415 (3)	C18—C19	1.385 (3)
C2—C3	1.523 (3)	C3—H3	1.0000
C3—C4	1.508 (3)	C6—H6	0.9500
C3—C14	1.523 (3)	C7—H7	0.9500
C4—C13	1.365 (3)	C8—H8	0.9500
C4—C5	1.433 (3)	C9—H9	0.9500
C5—C10	1.421 (3)	C11—H11	0.9500
C5—C6	1.419 (3)	C12—H12	0.9500
C6—C7	1.372 (3)	C15—H15	0.9500
C7—C8	1.396 (3)	C16—H16	0.9500
C8—C9	1.374 (3)	C17—H17	0.9500
C9—C10	1.416 (3)	C18—H18	0.9500
C10—C11	1.413 (3)	C19—H19	0.9500
C1—O1—C13	117.88 (15)	C15—C14—C19	119.01 (18)
H1N—N1—H2N	111 (2)	C14—C15—C16	120.1 (2)
C1—N1—H1N	122.0 (17)	C15—C16—C17	120.4 (2)
C1—N1—H2N	117.8 (18)	C16—C17—C18	119.7 (2)
O1—C1—C2	122.03 (17)	C17—C18—C19	120.1 (3)
O1—C1—N1	110.54 (17)	C14—C19—C18	120.8 (2)
N1—C1—C2	127.39 (19)	N2—C20—C2	178.9 (2)
C1—C2—C3	123.11 (17)	C2—C3—H3	107.00
C1—C2—C20	118.34 (19)	C4—C3—H3	107.00
C3—C2—C20	118.54 (18)	C14—C3—H3	107.00
C2—C3—C14	111.16 (16)	C5—C6—H6	120.00
C4—C3—C14	114.16 (16)	C7—C6—H6	120.00
C2—C3—C4	108.92 (16)	C6—C7—H7	120.00
C3—C4—C13	121.06 (17)	C8—C7—H7	120.00
C3—C4—C5	121.46 (17)	C7—C8—H8	120.00
C5—C4—C13	117.46 (17)	C9—C8—H8	120.00
C4—C5—C6	122.21 (18)	C8—C9—H9	120.00
C4—C5—C10	119.53 (17)	C10—C9—H9	120.00
C6—C5—C10	118.26 (18)	C10—C11—H11	120.00
C5—C6—C7	120.7 (2)	C12—C11—H11	120.00
C6—C7—C8	120.9 (2)	C11—C12—H12	121.00
C7—C8—C9	120.24 (19)	C13—C12—H12	121.00
C8—C9—C10	120.4 (2)	C14—C15—H15	120.00
C5—C10—C9	119.60 (19)	C16—C15—H15	120.00
C5—C10—C11	119.53 (17)	C15—C16—H16	120.00
C9—C10—C11	120.88 (19)	C17—C16—H16	120.00
C10—C11—C12	120.61 (18)	C16—C17—H17	120.00
C11—C12—C13	118.90 (18)	C18—C17—H17	120.00
O1—C13—C12	113.06 (16)	C17—C18—H18	120.00
O1—C13—C4	122.98 (17)	C19—C18—H18	120.00
C4—C13—C12	123.96 (18)	C14—C19—H19	120.00
C3—C14—C15	119.59 (17)	C18—C19—H19	120.00
C3—C14—C19	121.37 (18)
C13—O1—C1—N1	165.54 (17)	C5—C4—C13—O1	179.45 (17)
C13—O1—C1—C2	−12.3 (3)	C5—C4—C13—C12	−1.3 (3)
C1—O1—C13—C4	16.6 (3)	C4—C5—C6—C7	−179.59 (19)
C1—O1—C13—C12	−162.72 (17)	C10—C5—C6—C7	0.6 (3)
O1—C1—C2—C3	−6.1 (3)	C4—C5—C10—C9	179.43 (18)
O1—C1—C2—C20	174.79 (17)	C4—C5—C10—C11	−0.4 (3)
N1—C1—C2—C3	176.45 (19)	C6—C5—C10—C9	−0.8 (3)
N1—C1—C2—C20	−2.6 (3)	C6—C5—C10—C11	179.40 (18)
C1—C2—C3—C4	18.5 (3)	C5—C6—C7—C8	−0.1 (3)
C1—C2—C3—C14	−108.1 (2)	C6—C7—C8—C9	−0.3 (3)
C20—C2—C3—C4	−162.42 (17)	C7—C8—C9—C10	0.2 (3)
C20—C2—C3—C14	71.0 (2)	C8—C9—C10—C5	0.4 (3)
C2—C3—C4—C5	164.30 (17)	C8—C9—C10—C11	−179.78 (19)
C2—C3—C4—C13	−14.1 (3)	C5—C10—C11—C12	−0.7 (3)
C14—C3—C4—C5	−70.8 (2)	C9—C10—C11—C12	179.46 (19)
C14—C3—C4—C13	110.8 (2)	C10—C11—C12—C13	0.8 (3)
C2—C3—C14—C15	−85.4 (2)	C11—C12—C13—O1	179.53 (17)
C2—C3—C14—C19	92.2 (2)	C11—C12—C13—C4	0.2 (3)
C4—C3—C14—C15	150.88 (18)	C3—C14—C15—C16	177.37 (19)
C4—C3—C14—C19	−31.5 (3)	C19—C14—C15—C16	−0.3 (3)
C3—C4—C5—C6	3.1 (3)	C3—C14—C19—C18	−177.9 (2)
C3—C4—C5—C10	−177.07 (18)	C15—C14—C19—C18	−0.3 (3)
C13—C4—C5—C6	−178.44 (19)	C14—C15—C16—C17	0.7 (3)
C13—C4—C5—C10	1.4 (3)	C15—C16—C17—C18	−0.6 (4)
C3—C4—C13—O1	−2.1 (3)	C16—C17—C18—C19	0.1 (4)
C3—C4—C13—C12	177.14 (18)	C17—C18—C19—C14	0.4 (4)

Hydrogen-bond geometry (Å, º)

Cg2 and Cg3 are the centroids of the C4/C5/C10–C13 and C5–C10 rings, respectively.

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···N2^i	0.90 (3)	2.16 (2)	2.978 (3)	150 (2)
N1—H2N···N2^ii	0.87 (3)	2.33 (3)	3.138 (3)	154 (2)
C7—H7···Cg3^iii	0.95	2.84	3.561 (2)	133
C12—H12···Cg2^iv	0.95	2.68	3.446 (2)	139

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