3-[(1-Benzyl­amino)ethyl­idene]-2H-chromene-2,4(3H)-dione

The mol­ecule of the title compound, C₁₈H₁₅NO₃, adopts the keto–amine tautomeric form, with strong intra­molecular N—H...O hydrogen bonds classified as resonance-assisted hydrogen bonds (RAHBs). In the crystal structure, the mol­ecules are stabilized by C—H...O, C—H...π and π–π interactions, forming rings and chains.

Key indicators

• Single-crystal X-ray study
• T = 193 K
• Mean [sigma](C-C)= 0.002 Å
• R factor = 0.039
• wR factor = 0.110
• Data-to-parameter ratio = 13.3

checkCIF/PLATON results

No syntax errors found


No errors found in this datablock

---

Computing details

Data collection: WIN-XPOSE in X-AREA (Stoe & Cie, 2000); cell refinement: WIN-CELL in X-AREA; data reduction: WIN-INTEGRATE in X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: PARST97 (Nardelli, 1996).

3-[(1-Benzylamino)ethylidene]-2H-chromene-2,4(3H)-dione

Crystal data

C18H15NO3	Z = 2
Mr = 293.32	F(000) = 308
Triclinic, P1	Dx = 1.378 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.385 (2) Å	Cell parameters from 894 reflections
b = 9.403 (2) Å	θ = 2.7–26.2°
c = 9.871 (2) Å	µ = 0.09 mm^−1
α = 81.60 (2)°	T = 193 K
β = 85.35 (2)°	Block, colorless
γ = 66.75 (2)°	0.53 × 0.45 × 0.45 mm
V = 707.1 (3) Å^3

Data collection

Stoe IPDS-II diffractometer	1910 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.064
Graphite monochromator	θmax = 26.3°, θmin = 2.1°
Detector resolution: 150 pixels mm^-1	h = −10→10
φ scans	k = −11→11
7530 measured reflections	l = −12→12
2659 independent 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)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.110	H-atom parameters constrained
S = 0.99	w = 1/[σ^2(Fo^2) + (0.065P)^2] where P = (Fo^2 + 2Fc^2)/3
2659 reflections	(Δ/σ)max = 0.001
200 parameters	Δρmax = 0.15 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	0.06317 (13)	0.29380 (11)	1.20970 (9)	0.0347 (3)
C3	0.24242 (18)	0.21866 (15)	1.00482 (13)	0.0300 (3)
O4	0.36679 (14)	0.39510 (11)	0.89615 (10)	0.0372 (3)
N32	0.40595 (15)	0.14402 (13)	0.80209 (11)	0.0328 (3)
H32	0.4237	0.2282	0.8012	0.039*
O2	0.09519 (14)	0.07399 (11)	1.14150 (10)	0.0389 (3)
C10	0.19424 (18)	0.46657 (15)	1.09428 (13)	0.0306 (3)
C9	0.09226 (19)	0.42884 (15)	1.19914 (14)	0.0314 (3)
C311	0.2868 (2)	−0.03957 (17)	0.91521 (15)	0.0367 (3)
H31C	0.3528	−0.0978	0.8432	0.055*
H31B	0.1658	−0.0171	0.9060	0.055*
H31A	0.3248	−0.0998	1.0023	0.055*
C4	0.27465 (19)	0.35958 (16)	0.99045 (13)	0.0309 (3)
C8	0.0137 (2)	0.52555 (16)	1.29998 (14)	0.0364 (4)
H8	−0.0548	0.4987	1.3695	0.044*
C6	0.1423 (2)	0.70305 (16)	1.19065 (15)	0.0394 (4)
H6	0.1593	0.7954	1.1882	0.047*
C2	0.13324 (19)	0.18661 (16)	1.11615 (13)	0.0311 (3)
C7	0.0400 (2)	0.66227 (17)	1.29447 (15)	0.0393 (4)
H7	−0.0115	0.7281	1.3612	0.047*
C31	0.31298 (18)	0.10978 (15)	0.90596 (13)	0.0307 (3)
C5	0.2185 (2)	0.60584 (16)	1.09127 (14)	0.0353 (3)
H5	0.2866	0.6332	1.0217	0.042*
C33	0.4821 (2)	0.05289 (17)	0.68793 (14)	0.0378 (4)
H33B	0.3954	0.0250	0.6522	0.045*
H33A	0.5776	−0.0427	0.7204	0.045*
C331	0.5471 (2)	0.14451 (16)	0.57560 (14)	0.0346 (3)
C332	0.4312 (2)	0.27368 (18)	0.49745 (15)	0.0429 (4)
H332	0.3126	0.3052	0.5163	0.052*
C336	0.7220 (2)	0.09983 (19)	0.54473 (15)	0.0449 (4)
H336	0.8015	0.0145	0.5967	0.054*
C334	0.6652 (2)	0.30889 (19)	0.36051 (15)	0.0435 (4)
H334	0.7048	0.3630	0.2885	0.052*
C333	0.4907 (2)	0.35618 (18)	0.39147 (16)	0.0458 (4)
H333	0.4120	0.4438	0.3412	0.055*
C335	0.7809 (2)	0.1805 (2)	0.43708 (16)	0.0516 (5)
H335	0.8993	0.1478	0.4165	0.062*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0426 (6)	0.0329 (5)	0.0331 (5)	−0.0199 (5)	0.0084 (4)	−0.0076 (4)
C3	0.0313 (8)	0.0309 (7)	0.0280 (7)	−0.0128 (6)	−0.0001 (5)	−0.0026 (5)
O4	0.0453 (6)	0.0371 (5)	0.0336 (5)	−0.0224 (5)	0.0080 (4)	−0.0041 (4)
N32	0.0380 (7)	0.0340 (6)	0.0290 (6)	−0.0171 (5)	0.0035 (5)	−0.0051 (5)
O2	0.0492 (7)	0.0351 (5)	0.0382 (6)	−0.0238 (5)	0.0095 (5)	−0.0065 (4)
C10	0.0326 (8)	0.0295 (7)	0.0299 (7)	−0.0122 (6)	−0.0021 (5)	−0.0024 (5)
C9	0.0348 (8)	0.0285 (7)	0.0319 (7)	−0.0134 (6)	−0.0016 (6)	−0.0033 (5)
C311	0.0433 (9)	0.0359 (7)	0.0352 (7)	−0.0195 (7)	0.0050 (6)	−0.0085 (6)
C4	0.0327 (8)	0.0326 (7)	0.0278 (7)	−0.0140 (6)	−0.0015 (5)	−0.0006 (5)
C8	0.0374 (9)	0.0377 (8)	0.0329 (7)	−0.0137 (7)	0.0038 (6)	−0.0059 (6)
C6	0.0457 (10)	0.0308 (7)	0.0432 (8)	−0.0159 (7)	−0.0030 (7)	−0.0054 (6)
C2	0.0337 (8)	0.0307 (7)	0.0294 (7)	−0.0134 (6)	0.0001 (5)	−0.0034 (5)
C7	0.0415 (9)	0.0360 (8)	0.0399 (8)	−0.0126 (7)	0.0003 (6)	−0.0114 (6)
C31	0.0309 (8)	0.0325 (7)	0.0285 (7)	−0.0125 (6)	−0.0032 (5)	−0.0011 (5)
C5	0.0389 (9)	0.0339 (7)	0.0341 (7)	−0.0162 (6)	−0.0008 (6)	−0.0013 (6)
C33	0.0432 (9)	0.0380 (7)	0.0327 (7)	−0.0159 (7)	0.0060 (6)	−0.0096 (6)
C331	0.0402 (9)	0.0364 (7)	0.0278 (7)	−0.0147 (6)	0.0022 (6)	−0.0080 (5)
C332	0.0359 (9)	0.0420 (8)	0.0429 (9)	−0.0081 (7)	0.0051 (6)	−0.0040 (6)
C336	0.0368 (9)	0.0517 (9)	0.0388 (8)	−0.0125 (7)	−0.0012 (6)	0.0037 (7)
C334	0.0522 (10)	0.0497 (9)	0.0319 (7)	−0.0253 (8)	0.0025 (7)	−0.0015 (6)
C333	0.0494 (10)	0.0397 (8)	0.0404 (8)	−0.0113 (7)	0.0005 (7)	0.0010 (6)
C335	0.0377 (10)	0.0684 (11)	0.0441 (9)	−0.0207 (8)	0.0034 (7)	0.0050 (8)

Geometric parameters (Å, º)

O1—C9	1.3727 (17)	C6—C5	1.380 (2)
O1—C2	1.3894 (16)	C6—C7	1.391 (2)
C3—C31	1.4389 (19)	C6—H6	0.9300
C3—C4	1.439 (2)	C7—H7	0.9300
C3—C2	1.4471 (19)	C5—H5	0.9300
O4—C4	1.2534 (18)	C33—C331	1.504 (2)
N32—C31	1.3171 (18)	C33—H33B	0.9700
N32—C33	1.4647 (17)	C33—H33A	0.9700
N32—H32	0.8600	C331—C336	1.378 (2)
O2—C2	1.2092 (17)	C331—C332	1.389 (2)
C10—C9	1.385 (2)	C332—C333	1.389 (2)
C10—C5	1.398 (2)	C332—H332	0.9300
C10—C4	1.4733 (19)	C336—C335	1.387 (2)
C9—C8	1.392 (2)	C336—H336	0.9300
C311—C31	1.494 (2)	C334—C333	1.373 (2)
C311—H31C	0.9600	C334—C335	1.378 (2)
C311—H31B	0.9600	C334—H334	0.9300
C311—H31A	0.9600	C333—H333	0.9300
C8—C7	1.380 (2)	C335—H335	0.9300
C8—H8	0.9300
C9—O1—C2	122.40 (11)	C8—C7—H7	119.5
C31—C3—C4	120.60 (12)	C6—C7—H7	119.5
C31—C3—C2	118.77 (12)	N32—C31—C3	117.97 (13)
C4—C3—C2	120.60 (12)	N32—C31—C311	118.49 (12)
C31—N32—C33	126.43 (13)	C3—C31—C311	123.54 (13)
C31—N32—H32	116.8	C6—C5—C10	120.60 (14)
C33—N32—H32	116.8	C6—C5—H5	119.7
C9—C10—C5	118.41 (13)	C10—C5—H5	119.7
C9—C10—C4	119.57 (13)	N32—C33—C331	110.79 (12)
C5—C10—C4	122.02 (13)	N32—C33—H33B	109.5
O1—C9—C10	121.91 (12)	C331—C33—H33B	109.5
O1—C9—C8	116.22 (13)	N32—C33—H33A	109.5
C10—C9—C8	121.87 (13)	C331—C33—H33A	109.5
C31—C311—H31C	109.5	H33B—C33—H33A	108.1
C31—C311—H31B	109.5	C336—C331—C332	118.39 (14)
H31C—C311—H31B	109.5	C336—C331—C33	121.01 (13)
C31—C311—H31A	109.5	C332—C331—C33	120.57 (14)
H31C—C311—H31A	109.5	C333—C332—C331	120.68 (15)
H31B—C311—H31A	109.5	C333—C332—H332	119.7
O4—C4—C3	123.93 (13)	C331—C332—H332	119.7
O4—C4—C10	118.90 (13)	C331—C336—C335	120.85 (14)
C3—C4—C10	117.16 (12)	C331—C336—H336	119.6
C7—C8—C9	118.46 (14)	C335—C336—H336	119.6
C7—C8—H8	120.8	C333—C334—C335	119.41 (15)
C9—C8—H8	120.8	C333—C334—H334	120.3
C5—C6—C7	119.67 (14)	C335—C334—H334	120.3
C5—C6—H6	120.2	C334—C333—C332	120.29 (14)
C7—C6—H6	120.2	C334—C333—H333	119.9
O2—C2—O1	113.58 (12)	C332—C333—H333	119.9
O2—C2—C3	128.06 (13)	C334—C335—C336	120.36 (16)
O1—C2—C3	118.35 (12)	C334—C335—H335	119.8
C8—C7—C6	120.99 (14)	C336—C335—H335	119.8

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N32—H32···O4	0.86	1.83	2.554 (2)	141
C6—H6···O2^i	0.93	2.44	3.318 (2)	158
C334—H334···O4^ii	0.93	2.60	3.420 (2)	148
C311—H31B···O2^iii	0.96	2.55	3.440 (2)	156
C333—H333···Cg2^iv	0.93	2.72	3.528 (2)	147
C33—H33B···Cg3^v	0.97	2.81	3.572 (2)	136

Symmetry codes: (i) x, y+1, z; (ii) −x+1, −y+1, −z+1; (iii) −x, −y, −z+2; (iv) x, y, z−4; (v) −x+1, −y, −z+1.