(1α,12α)-Ethyl 15-eth­oxy-4-hydr­oxy-2-oxo-9-oxatetra­cyclo­[10.2.2.0^1,10.0^3,8]hexa­deca-4,6,8,13-tetra­ene-13-carboxyl­ate

(E)-Ethyl 3-(4-oxo-4H-chromen-3-yl)acrylate reacts in a Domino reaction with ethyl vinyl ether via inter­mediates to give the title bridged compound, C₂₀H₂₂O₆, and by-products. The conformation of the carboxyl­ate group in the mol­ecular structure is determined by intra­molecular hydrogen bonds. In the crystal structure, mol­ecules are linked via inter­molecular C—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 153 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.042
• wR factor = 0.113
• Data-to-parameter ratio = 16.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       2.86 Ratio
PLAT222_ALERT_3_C Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       3.38 Ratio
PLAT482_ALERT_4_C Small D-H..A Angle Rep for C13    ..  O5      ..      95.10 Deg.

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 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
   1 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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Computing details

Data collection: SMART (Bruker, 2002); cell refinement: SMART; data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXTL (Bruker, 2002); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

(1α,12α)-Ethyl 15-ethoxy-4-hydroxy-2-oxo-9-oxatetracyclo[10,2,2,01,10,3,8]hexadeca- 4,6,8,13-tetraene-13-carboxylate

Crystal data

C20H22O6	F(000) = 760
Mr = 358.38	Dx = 1.352 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 4611 reflections
a = 8.6328 (11) Å	θ = 2.3–28.0°
b = 11.3075 (15) Å	µ = 0.10 mm^−1
c = 18.312 (2) Å	T = 153 K
β = 99.909 (2)°	Prism, light green
V = 1760.8 (4) Å^3	0.35 × 0.30 × 0.23 mm
Z = 4

Data collection

Bruker SMART CCD area-detector diffractometer	4027 independent reflections
Radiation source: sealed tube	3367 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.028
φ and ω scans	θmax = 27.5°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2002)	h = −11→11
Tmin = 0.944, Tmax = 0.973	k = −14→14
19861 measured reflections	l = −23→23

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: difference Fourier map
wR(F^2) = 0.113	H-atom parameters constrained
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0567P)^2 + 0.5098P] where P = (Fo^2 + 2Fc^2)/3
4027 reflections	(Δ/σ)max < 0.001
238 parameters	Δρmax = 0.35 e Å^−3
0 restraints	Δρmin = −0.21 e Å^−3

Special details

Experimental. Spectroscopic analysis: IR (KBr, ν, cm^-1): 3432, 1714, 1639, 1236, 1090; ¹H NMR (CDCl₃, δ, p.p.m.): 0.9 (t, 3H, J = 7.0 Hz, OCH₂CH₃), 1.32 (t, 3H, J = 7.1 Hz, CO₂CH₂CH₃), 1.44 (dddd, 1H, J¹ = 13.0 Hz, J² = 3.4 Hz, J³ = 3.1 Hz, J⁴ = 3.1 Hz, 16β-H), 1.65 (ddd, 1H, J¹ = 13.8 Hz, J² = 3.4 Hz, J³ = 2.8 Hz, 11α-H), 2.02 (dddd, 1H, J¹ = 13.8 Hz, J² = 10.0 Hz, J³ = 3.3 Hz, J⁴ = 3.1 Hz, 11β-H), 2.33 (ddd, 1H, J¹ = 13.0 Hz, J² = 8.1 Hz, J³ = 2.8 Hz, 16α-H), 3.14 (dq, 1H, J¹ = 9.5 Hz, J² = 7.1 Hz, OCHHCH₃), 3.33 (dq, 1H, J¹ = 9.5 Hz, J² = 7.1 Hz, OCHHCH₃), 3.42 (m, 1H, 12-H), 4.23 (q, 2H, J = 7.1 Hz, CO₂CH₂CH₃), 4.25 (dd, 1H, J¹ = 10.0 Hz, J² = 3.4 Hz, 10-H), 4.31 (dd, 1H, J¹ = 8.1 Hz, J¹ = 3.1 Hz, 15-H), 6.45 (dd, 1H, J¹ = 8.2 Hz, J² = 1.0 Hz, 7-H), 6.58 (dd, 1H, J¹ = 8.4 Hz, J² = 1.0 Hz, 5-H), 7.38 (dd, 1H, J¹ = 8.4 Hz, J² = 8.2 Hz, 6-H), 7.44 (s, 1H, 14-H), 11.80 (s, 1H, 4-OH); ¹³C NMR (CDCl₃, δ, p.p.m.): 14.2 (CO₂CH₂CH₃), 15.0 (OCH₂CH₃), 29.9 (C12), 31.7 (C11), 36.6 (C16), 54.2 (C1), 60.9 (CO₂CH₂CH₃), 65.3 (OCH₂CH₃), 74.8 (C15), 77.4 (C10), 107.0 (C3), 107.3 (C7), 110.0 (C5), 134.3 (C14), 137.9 (C6), 140.1 (C13), 161.0 (C8), 162.6 (C4), 164.1 (CO₂Et), 198.3 (C2).

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	−0.10769 (12)	0.86656 (9)	−0.08510 (5)	0.0297 (2)
H1	−0.0102	0.8684	−0.0698	0.045*
O2	0.15061 (11)	0.86675 (9)	0.00976 (5)	0.0261 (2)
O3	−0.10733 (10)	0.82664 (8)	0.17698 (5)	0.0239 (2)
O4	0.58625 (13)	0.94340 (11)	0.32427 (6)	0.0408 (3)
O5	0.57295 (11)	1.02671 (9)	0.21213 (5)	0.0297 (2)
O6	0.26973 (11)	0.64466 (9)	0.11281 (6)	0.0286 (2)
C1	−0.18340 (16)	0.84840 (12)	−0.02721 (7)	0.0238 (3)
C2	−0.34518 (17)	0.83460 (13)	−0.04062 (8)	0.0297 (3)
H2A	−0.4024	0.8387	−0.0897	0.036*
C3	−0.42247 (17)	0.81468 (13)	0.01850 (9)	0.0320 (3)
H3A	−0.5332	0.8036	0.0091	0.038*
C4	−0.34289 (16)	0.81047 (13)	0.09102 (8)	0.0285 (3)
H4A	−0.3982	0.7961	0.1307	0.034*
C5	−0.18173 (15)	0.82752 (11)	0.10463 (7)	0.0221 (3)
C6	−0.09785 (14)	0.84423 (11)	0.04589 (7)	0.0205 (3)
C7	0.07302 (15)	0.85160 (11)	0.05977 (7)	0.0197 (3)
C8	0.15243 (14)	0.83674 (11)	0.13917 (7)	0.0188 (3)
C9	0.04307 (14)	0.88647 (12)	0.19031 (7)	0.0209 (3)
H9A	0.0260	0.9728	0.1800	0.025*
C10	0.11691 (16)	0.86998 (13)	0.27195 (7)	0.0257 (3)
H10A	0.0527	0.8144	0.2960	0.031*
H10B	0.1206	0.9467	0.2982	0.031*
C11	0.28449 (16)	0.82078 (12)	0.27623 (7)	0.0248 (3)
H11A	0.3412	0.8174	0.3286	0.030*
C12	0.37130 (15)	0.89657 (11)	0.22899 (7)	0.0224 (3)
C13	0.30577 (14)	0.90164 (11)	0.15752 (7)	0.0202 (3)
H13A	0.3521	0.9427	0.1215	0.024*
C14	0.52038 (15)	0.95599 (12)	0.26114 (8)	0.0251 (3)
C15	0.72453 (16)	1.08294 (14)	0.23639 (9)	0.0325 (3)
H15A	0.8069	1.0225	0.2514	0.039*
H15B	0.7200	1.1355	0.2792	0.039*
C16	0.75988 (18)	1.15290 (15)	0.17181 (11)	0.0430 (4)
H16A	0.7569	1.1006	0.1289	0.064*
H16B	0.8646	1.1884	0.1845	0.064*
H16C	0.6812	1.2155	0.1597	0.064*
C17	0.27053 (18)	0.69689 (12)	0.24036 (8)	0.0288 (3)
H17A	0.3770	0.6643	0.2405	0.035*
H17B	0.2148	0.6433	0.2699	0.035*
C18	0.18060 (15)	0.70249 (11)	0.16024 (7)	0.0222 (3)
H18A	0.0769	0.6618	0.1574	0.027*
C19	0.17864 (18)	0.57508 (14)	0.05541 (9)	0.0346 (3)
H19A	0.1051	0.6265	0.0221	0.042*
H19B	0.1163	0.5156	0.0775	0.042*
C20	0.2876 (2)	0.51497 (18)	0.01275 (11)	0.0540 (5)
H20A	0.3471	0.5744	−0.0099	0.081*
H20B	0.2269	0.4660	−0.0262	0.081*
H20C	0.3606	0.4648	0.0462	0.081*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0289 (5)	0.0389 (6)	0.0198 (5)	−0.0023 (4)	−0.0001 (4)	0.0006 (4)
O2	0.0236 (5)	0.0346 (5)	0.0208 (5)	−0.0027 (4)	0.0060 (4)	0.0007 (4)
O3	0.0199 (5)	0.0302 (5)	0.0222 (5)	−0.0036 (4)	0.0052 (4)	0.0013 (4)
O4	0.0353 (6)	0.0504 (7)	0.0316 (6)	−0.0076 (5)	−0.0085 (5)	0.0000 (5)
O5	0.0210 (5)	0.0323 (5)	0.0342 (5)	−0.0076 (4)	0.0000 (4)	−0.0029 (4)
O6	0.0241 (5)	0.0271 (5)	0.0334 (5)	0.0030 (4)	0.0018 (4)	−0.0081 (4)
C1	0.0255 (7)	0.0207 (6)	0.0240 (6)	−0.0001 (5)	0.0008 (5)	−0.0007 (5)
C2	0.0263 (7)	0.0303 (7)	0.0288 (7)	−0.0012 (6)	−0.0053 (5)	−0.0016 (6)
C3	0.0191 (7)	0.0332 (8)	0.0418 (8)	−0.0006 (6)	−0.0005 (6)	−0.0036 (6)
C4	0.0206 (7)	0.0308 (7)	0.0350 (7)	−0.0005 (5)	0.0071 (5)	−0.0013 (6)
C5	0.0215 (6)	0.0199 (6)	0.0246 (6)	0.0014 (5)	0.0030 (5)	0.0004 (5)
C6	0.0206 (6)	0.0192 (6)	0.0211 (6)	0.0000 (5)	0.0019 (5)	−0.0004 (5)
C7	0.0212 (6)	0.0171 (6)	0.0207 (6)	−0.0008 (5)	0.0030 (5)	−0.0005 (5)
C8	0.0184 (6)	0.0186 (6)	0.0191 (6)	−0.0001 (5)	0.0020 (5)	0.0007 (5)
C9	0.0199 (6)	0.0215 (6)	0.0214 (6)	−0.0016 (5)	0.0041 (5)	0.0004 (5)
C10	0.0291 (7)	0.0295 (7)	0.0187 (6)	−0.0039 (5)	0.0051 (5)	0.0010 (5)
C11	0.0290 (7)	0.0227 (6)	0.0202 (6)	−0.0015 (5)	−0.0026 (5)	0.0024 (5)
C12	0.0215 (6)	0.0191 (6)	0.0253 (6)	0.0018 (5)	0.0008 (5)	−0.0020 (5)
C13	0.0185 (6)	0.0180 (6)	0.0242 (6)	0.0012 (5)	0.0037 (5)	−0.0005 (5)
C14	0.0221 (6)	0.0231 (6)	0.0286 (7)	0.0034 (5)	−0.0002 (5)	−0.0056 (5)
C15	0.0186 (7)	0.0324 (8)	0.0451 (9)	−0.0039 (6)	0.0019 (6)	−0.0135 (7)
C16	0.0233 (7)	0.0400 (9)	0.0658 (12)	−0.0076 (7)	0.0080 (7)	0.0012 (8)
C17	0.0355 (8)	0.0206 (6)	0.0266 (7)	−0.0007 (6)	−0.0047 (6)	0.0037 (5)
C18	0.0232 (6)	0.0184 (6)	0.0241 (6)	−0.0002 (5)	0.0014 (5)	−0.0007 (5)
C19	0.0361 (8)	0.0310 (8)	0.0353 (8)	−0.0006 (6)	0.0019 (6)	−0.0100 (6)
C20	0.0580 (12)	0.0548 (11)	0.0499 (11)	0.0087 (9)	0.0116 (9)	−0.0206 (9)

Geometric parameters (Å, º)

O1—C1	1.3534 (16)	C10—C11	1.5393 (19)
O1—H1	0.8400	C10—H10A	0.9900
O2—C7	1.2360 (15)	C10—H10B	0.9900
O3—C5	1.3694 (15)	C11—C12	1.5058 (19)
O3—C9	1.4470 (15)	C11—C17	1.5431 (19)
O4—C14	1.2057 (16)	C11—H11A	1.0000
O5—C14	1.3384 (17)	C12—C13	1.3346 (18)
O5—C15	1.4539 (16)	C12—C14	1.4810 (18)
O6—C18	1.4155 (16)	C13—H13A	0.9500
O6—C19	1.4345 (17)	C15—C16	1.497 (2)
C1—C2	1.385 (2)	C15—H15A	0.9900
C1—C6	1.4139 (18)	C15—H15B	0.9900
C2—C3	1.384 (2)	C16—H16A	0.9800
C2—H2A	0.9500	C16—H16B	0.9800
C3—C4	1.387 (2)	C16—H16C	0.9800
C3—H3A	0.9500	C17—C18	1.5387 (18)
C4—C5	1.3841 (19)	C17—H17A	0.9900
C4—H4A	0.9500	C17—H17B	0.9900
C5—C6	1.4089 (18)	C18—H18A	1.0000
C6—C7	1.4555 (17)	C19—C20	1.487 (2)
C7—C8	1.5063 (17)	C19—H19A	0.9900
C8—C13	1.5002 (17)	C19—H19B	0.9900
C8—C9	1.5456 (17)	C20—H20A	0.9800
C8—C18	1.5748 (17)	C20—H20B	0.9800
C9—C10	1.5324 (17)	C20—H20C	0.9800
C9—H9A	1.0000
C1—O1—H1	109.5	C10—C11—H11A	111.3
C5—O3—C9	114.7 (1)	C17—C11—H11A	111.3
C14—O5—C15	116.6 (1)	C13—C12—C14	124.26 (13)
C18—O6—C19	114.6 (1)	C13—C12—C11	114.76 (11)
O1—C1—C2	119.11 (12)	C14—C12—C11	120.95 (11)
O1—C1—C6	120.17 (12)	C12—C13—C8	114.05 (12)
C2—C1—C6	120.71 (13)	C12—C13—H13A	123.0
C3—C2—C1	119.13 (13)	C8—C13—H13A	123.0
C3—C2—H2A	120.4	O4—C14—O5	123.72 (13)
C1—C2—H2A	120.4	O4—C14—C12	124.18 (13)
C2—C3—C4	121.90 (13)	O5—C14—C12	112.10 (11)
C2—C3—H3A	119.1	O5—C15—C16	106.54 (12)
C4—C3—H3A	119.1	O5—C15—H15A	110.4
C5—C4—C3	118.98 (13)	C16—C15—H15A	110.4
C5—C4—H4A	120.5	O5—C15—H15B	110.4
C3—C4—H4A	120.5	C16—C15—H15B	110.4
O3—C5—C4	117.57 (12)	H15A—C15—H15B	108.6
O3—C5—C6	121.50 (11)	C15—C16—H16A	109.5
C4—C5—C6	120.93 (12)	C15—C16—H16B	109.5
C5—C6—C1	118.28 (12)	H16A—C16—H16B	109.5
C5—C6—C7	120.86 (11)	C15—C16—H16C	109.5
C1—C6—C7	120.80 (12)	H16A—C16—H16C	109.5
O2—C7—C6	122.72 (11)	H16B—C16—H16C	109.5
O2—C7—C8	121.06 (11)	C18—C17—C11	110.98 (10)
C6—C7—C8	116.20 (11)	C18—C17—H17A	109.4
C13—C8—C7	113.5 (1)	C11—C17—H17A	109.4
C13—C8—C9	107.1 (1)	C18—C17—H17B	109.4
C7—C8—C9	108.7 (1)	C11—C17—H17B	109.4
C13—C8—C18	108.9 (1)	H17A—C17—H17B	108.0
C7—C8—C18	111.7 (1)	O6—C18—C17	109.1 (1)
C9—C8—C18	106.7 (1)	O6—C18—C8	111.9 (1)
O3—C9—C10	108.55 (10)	C17—C18—C8	107.7 (1)
O3—C9—C8	110.59 (10)	O6—C18—H18A	109.4
C10—C9—C8	110.60 (10)	C17—C18—H18A	109.4
O3—C9—H9A	109.0	C8—C18—H18A	109.4
C10—C9—H9A	109.0	O6—C19—C20	108.61 (13)
C8—C9—H9A	109.0	O6—C19—H19A	110.0
C9—C10—C11	108.85 (11)	C20—C19—H19A	110.0
C9—C10—H10A	109.9	O6—C19—H19B	110.0
C11—C10—H10A	109.9	C20—C19—H19B	110.0
C9—C10—H10B	109.9	H19A—C19—H19B	108.3
C11—C10—H10B	109.9	C19—C20—H20A	109.5
H10A—C10—H10B	108.3	C19—C20—H20B	109.5
C12—C11—C10	108.75 (11)	H20A—C20—H20B	109.5
C12—C11—C17	106.40 (11)	C19—C20—H20C	109.5
C10—C11—C17	107.61 (11)	H20A—C20—H20C	109.5
C12—C11—H11A	111.3	H20B—C20—H20C	109.5
O1—C1—C2—C3	179.27 (13)	O3—C9—C10—C11	127.40 (11)
C6—C1—C2—C3	−1.0 (2)	C8—C9—C10—C11	5.91 (14)
C1—C2—C3—C4	1.3 (2)	C9—C10—C11—C12	50.59 (14)
C2—C3—C4—C5	0.5 (2)	C9—C10—C11—C17	−64.28 (13)
C9—O3—C5—C4	−158.07 (12)	C10—C11—C12—C13	−59.52 (15)
C9—O3—C5—C6	22.40 (16)	C17—C11—C12—C13	56.13 (15)
C3—C4—C5—O3	177.93 (12)	C10—C11—C12—C14	122.44 (13)
C3—C4—C5—C6	−2.5 (2)	C17—C11—C12—C14	−121.90 (13)
O3—C5—C6—C1	−177.72 (11)	C14—C12—C13—C8	−178.37 (11)
C4—C5—C6—C1	2.76 (19)	C11—C12—C13—C8	3.67 (16)
O3—C5—C6—C7	5.04 (19)	C7—C8—C13—C12	175.15 (11)
C4—C5—C6—C7	−174.48 (12)	C9—C8—C13—C12	55.21 (14)
O1—C1—C6—C5	178.74 (12)	C18—C8—C13—C12	−59.77 (14)
C2—C1—C6—C5	−0.95 (19)	C15—O5—C14—O4	5.0 (2)
O1—C1—C6—C7	−4.02 (19)	C15—O5—C14—C12	−175.76 (11)
C2—C1—C6—C7	176.28 (12)	C13—C12—C14—O4	−173.52 (14)
C5—C6—C7—O2	−179.66 (12)	C11—C12—C14—O4	4.3 (2)
C1—C6—C7—O2	3.17 (19)	C13—C12—C14—O5	7.22 (18)
C5—C6—C7—C8	1.77 (17)	C11—C12—C14—O5	−174.94 (11)
C1—C6—C7—C8	−175.40 (11)	C14—O5—C15—C16	177.96 (12)
O2—C7—C8—C13	30.40 (16)	C12—C11—C17—C18	−59.62 (14)
C6—C7—C8—C13	−151.00 (11)	C10—C11—C17—C18	56.80 (14)
O2—C7—C8—C9	149.42 (12)	C19—O6—C18—C17	140.49 (12)
C6—C7—C8—C9	−31.98 (14)	C19—O6—C18—C8	−100.40 (13)
O2—C7—C8—C18	−93.16 (14)	C11—C17—C18—O6	128.76 (12)
C6—C7—C8—C18	85.43 (13)	C11—C17—C18—C8	7.11 (15)
C5—O3—C9—C10	−175.78 (10)	C13—C8—C18—O6	−69.41 (13)
C5—O3—C9—C8	−54.27 (13)	C7—C8—C18—O6	56.74 (13)
C13—C8—C9—O3	−178.95 (10)	C9—C8—C18—O6	175.35 (10)
C7—C8—C9—O3	58.05 (13)	C13—C8—C18—C17	50.52 (14)
C18—C8—C9—O3	−62.50 (12)	C7—C8—C18—C17	176.67 (11)
C13—C8—C9—C10	−58.67 (13)	C9—C8—C18—C17	−64.72 (13)
C7—C8—C9—C10	178.33 (10)	C18—O6—C19—C20	−177.06 (13)
C18—C8—C9—C10	57.78 (13)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O2	0.84	1.83	2.580 (1)	148
C11—H11A···O4	1.00	2.56	2.949 (2)	103
C13—H13A···O5	0.95	2.49	2.743 (2)	95
C15—H15B···O3^i	0.99	2.56	3.419 (2)	146

Symmetry code: (i) −x+1/2, y+1/2, −z+1/2.