5-Formyl-2,3-dihydro­isocoumarin

The title compound, erythrocentaurin, C₁₀H₈O₃, is a furocoumarin which was isolated from Enicostema hyssopifolium. The crystal structure is stabilized by intra­molecular C—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.069
• wR factor = 0.143
• Data-to-parameter ratio = 13.3

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT199_ALERT_1_C Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_C Check the Reported _diffrn_ambient_temperature .        293 K
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          1
              C10 H8 O3

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

   3 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
   0 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 1997); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003).

5-Formyl-2,3-dihydroisocoumarin

Crystal data

C10H8O3	Dx = 1.448 Mg m^−3
Mr = 176.16	Melting point = 413–414 K
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 7.651 (3) Å	Cell parameters from 2249 reflections
b = 4.0197 (14) Å	θ = 1.5–25.0°
c = 26.701 (9) Å	µ = 0.11 mm^−1
β = 100.337 (9)°	T = 293 K
V = 807.9 (5) Å^3	Plate, colorless
Z = 4	0.37 × 0.11 × 0.07 mm
F(000) = 368

Data collection

Siemens SMART CCD area-detector diffractometer	1573 independent reflections
Radiation source: fine-focus sealed tube	1151 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.031
Detector resolution: 8.33 pixels mm^-1	θmax = 26.0°, θmin = 1.6°
ω scans	h = −6→9
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	k = −4→4
Tmin = 0.961, Tmax = 0.993	l = −32→32
4155 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)] = 0.069	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.143	H-atom parameters constrained
S = 1.17	w = 1/[σ^2(Fo^2) + (0.0527P)^2 + 0.2194P] where P = (Fo^2 + 2Fc^2)/3
1573 reflections	(Δ/σ)max < 0.001
118 parameters	Δρmax = 0.19 e Å^−3
0 restraints	Δρmin = −0.23 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	0.0208 (2)	−0.9988 (5)	−0.09342 (7)	0.0495 (5)
O2	−0.0825 (3)	−1.0212 (6)	−0.17496 (8)	0.0675 (7)
O3	0.6988 (3)	−0.6428 (6)	−0.04433 (8)	0.0678 (7)
C1	0.5010 (3)	−0.5840 (6)	−0.12432 (9)	0.0358 (6)
C2	0.5005 (4)	−0.4717 (7)	−0.17383 (10)	0.0461 (7)
H2A	0.6027	−0.3748	−0.1816	0.055*
C3	0.3524 (4)	−0.5012 (7)	−0.21131 (10)	0.0488 (7)
H3A	0.3543	−0.4238	−0.2440	0.059*
C4	0.2021 (4)	−0.6458 (7)	−0.19996 (9)	0.0449 (7)
H4A	0.1022	−0.6702	−0.2253	0.054*
C5	0.0339 (4)	−0.9295 (7)	−0.14173 (10)	0.0439 (7)
C6	0.1384 (3)	−0.8274 (7)	−0.05287 (9)	0.0434 (7)
H6A	0.1281	−0.9273	−0.0205	0.052*
H6B	0.1024	−0.5964	−0.0521	0.052*
C7	0.3288 (3)	−0.8436 (6)	−0.05989 (9)	0.0369 (6)
H7A	0.3713	−1.0709	−0.0553	0.044*
H7B	0.4016	−0.7061	−0.0345	0.044*
C8	0.3455 (3)	−0.7246 (6)	−0.11220 (8)	0.0322 (6)
C9	0.1980 (3)	−0.7561 (6)	−0.15088 (9)	0.0350 (6)
C10	0.6681 (4)	−0.5423 (7)	−0.08733 (11)	0.0486 (7)
H10A	0.7589	−0.4260	−0.0985	0.058*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0381 (11)	0.0610 (13)	0.0498 (11)	−0.0156 (10)	0.0088 (9)	0.0005 (9)
O2	0.0412 (13)	0.0954 (17)	0.0592 (13)	−0.0216 (12)	−0.0088 (10)	−0.0093 (12)
O3	0.0389 (12)	0.111 (2)	0.0497 (13)	−0.0046 (12)	−0.0037 (10)	0.0022 (12)
C1	0.0303 (14)	0.0374 (14)	0.0404 (14)	0.0008 (11)	0.0079 (11)	−0.0031 (11)
C2	0.0445 (17)	0.0462 (16)	0.0523 (17)	−0.0029 (13)	0.0214 (14)	0.0023 (13)
C3	0.0569 (19)	0.0558 (17)	0.0350 (14)	0.0027 (15)	0.0121 (13)	0.0080 (13)
C4	0.0446 (16)	0.0517 (17)	0.0354 (14)	0.0023 (14)	−0.0014 (12)	0.0001 (12)
C5	0.0357 (16)	0.0480 (16)	0.0467 (16)	−0.0030 (13)	0.0042 (13)	−0.0021 (13)
C6	0.0417 (15)	0.0506 (16)	0.0401 (15)	−0.0038 (14)	0.0133 (12)	0.0015 (12)
C7	0.0348 (14)	0.0398 (14)	0.0351 (13)	−0.0012 (12)	0.0037 (11)	0.0027 (11)
C8	0.0312 (14)	0.0295 (13)	0.0367 (13)	0.0009 (11)	0.0081 (11)	−0.0026 (10)
C9	0.0310 (14)	0.0355 (14)	0.0372 (14)	0.0019 (11)	0.0031 (11)	−0.0022 (10)
C10	0.0319 (16)	0.0570 (18)	0.0579 (18)	−0.0041 (13)	0.0109 (13)	−0.0001 (14)

Geometric parameters (Å, º)

O1—C5	1.341 (3)	C4—C9	1.389 (3)
O1—C6	1.452 (3)	C4—H4A	0.9300
O2—C5	1.197 (3)	C5—C9	1.494 (4)
O3—C10	1.200 (3)	C6—C7	1.503 (3)
C1—C2	1.396 (3)	C6—H6A	0.9700
C1—C8	1.406 (3)	C6—H6B	0.9700
C1—C10	1.479 (4)	C7—C8	1.503 (3)
C2—C3	1.376 (4)	C7—H7A	0.9700
C2—H2A	0.9300	C7—H7B	0.9700
C3—C4	1.370 (4)	C8—C9	1.392 (3)
C3—H3A	0.9300	C10—H10A	0.9300
C5—O1—C6	118.4 (2)	O1—C6—H6B	109.3
C2—C1—C8	119.3 (2)	C7—C6—H6B	109.3
C2—C1—C10	116.8 (2)	H6A—C6—H6B	107.9
C8—C1—C10	123.9 (2)	C6—C7—C8	110.4 (2)
C3—C2—C1	121.5 (3)	C6—C7—H7A	109.6
C3—C2—H2A	119.3	C8—C7—H7A	109.6
C1—C2—H2A	119.3	C6—C7—H7B	109.6
C4—C3—C2	119.4 (2)	C8—C7—H7B	109.6
C4—C3—H3A	120.3	H7A—C7—H7B	108.1
C2—C3—H3A	120.3	C9—C8—C1	118.2 (2)
C3—C4—C9	120.4 (2)	C9—C8—C7	117.9 (2)
C3—C4—H4A	119.8	C1—C8—C7	123.9 (2)
C9—C4—H4A	119.8	C4—C9—C8	121.2 (2)
O2—C5—O1	118.4 (2)	C4—C9—C5	117.7 (2)
O2—C5—C9	123.9 (3)	C8—C9—C5	121.0 (2)
O1—C5—C9	117.7 (2)	O3—C10—C1	126.7 (3)
O1—C6—C7	111.8 (2)	O3—C10—H10A	116.6
O1—C6—H6A	109.3	C1—C10—H10A	116.6
C7—C6—H6A	109.3
C8—C1—C2—C3	−1.2 (4)	C6—C7—C8—C1	153.4 (2)
C10—C1—C2—C3	179.4 (2)	C3—C4—C9—C8	−0.3 (4)
C1—C2—C3—C4	−0.4 (4)	C3—C4—C9—C5	−176.4 (2)
C2—C3—C4—C9	1.2 (4)	C1—C8—C9—C4	−1.3 (4)
C6—O1—C5—O2	−166.4 (3)	C7—C8—C9—C4	178.7 (2)
C6—O1—C5—C9	16.4 (3)	C1—C8—C9—C5	174.7 (2)
C5—O1—C6—C7	−49.6 (3)	C7—C8—C9—C5	−5.3 (3)
O1—C6—C7—C8	52.8 (3)	O2—C5—C9—C4	11.2 (4)
C2—C1—C8—C9	2.1 (4)	O1—C5—C9—C4	−171.8 (2)
C10—C1—C8—C9	−178.7 (2)	O2—C5—C9—C8	−164.9 (3)
C2—C1—C8—C7	−178.0 (2)	O1—C5—C9—C8	12.0 (4)
C10—C1—C8—C7	1.3 (4)	C2—C1—C10—O3	−174.4 (3)
C6—C7—C8—C9	−26.6 (3)	C8—C1—C10—O3	6.3 (5)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7B···O3	0.97	2.35	2.902 (3)	115