3-(4-Bromo­benzyl­idene)-1,5-dioxaspiro­[5.5]undecane-2,4-dione

The title mol­ecule, C₁₆H₁₅BrO₄, was prepared by the reaction of (R)-2,4-dioxo-1,5-dioxaspiro­[5.5]undecane and 4-bromo­benzaldehyde with ethanol. The 1,3-dioxane ring exhibits a distorted boat and the fused cyclo­hexane ring exhibits a chair conformation.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.007 Å
• R factor = 0.040
• wR factor = 0.124
• Data-to-parameter ratio = 17.0

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT934_ALERT_3_B Number of (Iobs-Icalc)/SigmaW .gt. 10 Outliers .          1

Alert level C
PLAT057_ALERT_3_C Correction for Absorption Required   RT(exp) ...       1.12
PLAT230_ALERT_2_C Hirshfeld Test Diff for    O3     --  C10     ..       5.04 su
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C1     --  C6      ..       6.81 su
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C2     --  C3      ..       5.22 su
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C1
PLAT341_ALERT_3_C Low Bond Precision on  C-C Bonds (x 1000) Ang ..          7
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          2
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          5
PLAT915_ALERT_3_C Low Friedel Pair Coverage ......................      89.62 Perc.
PLAT737_ALERT_1_C D...A   Calc    3.005(6), Rep    3.004(2) ......       3.00 su-Ra
              C5   -O2      1.555   1.555                    #         38
PLAT737_ALERT_1_C D...A   Calc    2.809(6), Rep    2.812(2) ......       3.00 su-Ra
              C7   -O1      1.555   1.555                    #         38
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600          2

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.48
           From the CIF: _reflns_number_total               3243
           Count of symmetry unique reflns         1784
           Completeness (_total/calc)            181.78%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      1459
           Fraction of Friedel pairs measured     0.818
           Are heavy atom types Z>Si present        yes
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          2
PLAT033_ALERT_4_G Flack x Parameter Value Deviates from Zero .....      -0.03
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported   _diffrn_ambient_temperature        293 K

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

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

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S1. Comment

We have recently reported the crystal structure of 3-(2-Furylmethylene)-1,5-dioxaspiro[5.5]undecane-2,4-dione (Zeng & Jian, 2009) and 3-[(5-Methylfuran-2-yl)methylene]-1,5-dioxaspiro- [5.5]undecane-2,4-dione (Zeng et al. 2009). As part of our ongoing studies on new spiro compounds with potentially higher bioactivity, the title compound, (I) (Fig. 1), has been synthesized and its structure is determined here. The crystal structure analysis confirms the title compound with atom C7 connected by the 1,3-dioxane ring via C4-C7 single bond [1.462 (7)Å] and the phenyl ring via C7═C9 double bond [1.328 (7)Å]. In (I) (Fig. 1), the 1,3-dioxane ring has a distorted boat conformation. The four atoms (O3/C10/C8/O4)are approximately planar with an rms deviation of 0.0279 Å. The max. deviation from the mean plane is 0.029 (1) Å, and atoms C9 and C12 deviate -0.245 (2)Å and -0.567 (2) Å, respectively. Thus, the cyclohexane ring exists in a chair comformation (Cremer & Pople, 1975) with the puckering parameters Q =0.560 (5)Å, θ =3.9 (5)°, ϕ = 312 (10)°.

Related literature

For puckering parameters, see: Cremer & Pople (1975). For background information and related structures, see: Zeng & Jian (2009); Zeng et al. (2009).

S2. Experimental

The mixture of malonic acid (6.24 g, 0.06 mol) and acetic anhydride(9 ml) in strong sulfuric acid (0.25 ml) was stirred with water at 303 K. After dissolving, cyclohexanone (5.88 g, 0.06 mol) was added dropwise into the solution for 1 h. The reaction was allowed to proceed for 4 h. The mixture was cooled and filtered, and then an ethanol solution of 4-bromobenzaldehyde (11.04 g,0.06 mol) was added. The solution was then filtered and concentrated. Single crystals were obtained by evaporation of an ethanol solution of (I) at room temperature over a period of one week.

S3. Refinement

The H atoms were placed in calculated positions (C—H = 0.93–0.97 Å), and refined as riding with U_iso(H) = 1.2U_eq(C).

Computing details

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures

Fig. 1. The molecular structure of (I), drawn with 30% probability ellipsoids and spheres of arbritrary size for the H atoms.

3-(4-Bromobenzylidene)-1,5-dioxaspiro[5.5]undecane-2,4-dione

Crystal data

C16H15BrO4	F(000) = 712
Mr = 351.18	Dx = 1.568 Mg m^−3
Orthorhombic, Pna21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2n	Cell parameters from 2042 reflections
a = 6.6008 (13) Å	θ = 3.0–27.5°
b = 16.784 (3) Å	µ = 2.78 mm^−1
c = 13.424 (3) Å	T = 293 K
V = 1487.2 (5) Å^3	Block, yellow
Z = 4	0.18 × 0.12 × 0.10 mm

Data collection

Bruker SMART CCD area-detector diffractometer	2042 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.065
Graphite monochromator	θmax = 27.5°, θmin = 3.0°
ϕ and ω scans	h = −8→8
12420 measured reflections	k = −21→21
3243 independent reflections	l = −17→17

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F^2 > 2σ(F^2)] = 0.040	w = 1/[σ^2(Fo^2) + (0.0603P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.124	(Δ/σ)max < 0.001
S = 0.93	Δρmax = 0.31 e Å^−3
3243 reflections	Δρmin = −0.34 e Å^−3
191 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
2 restraints	Extinction coefficient: 0.0088 (18)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 1459 Friedel pairs
Secondary atom site location: difference Fourier map	Absolute structure parameter: −0.033 (13)

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
Br1	−0.30705 (7)	0.16937 (3)	0.44191 (6)	0.0845 (2)
O4	0.3239 (4)	0.18964 (18)	−0.1213 (2)	0.0495 (7)
C8	0.2952 (5)	0.1895 (3)	−0.0213 (4)	0.0474 (9)
C10	0.5373 (7)	0.0731 (3)	−0.0208 (4)	0.0683 (13)
O3	0.5363 (4)	0.07733 (19)	−0.1204 (2)	0.0628 (8)
O2	0.2192 (4)	0.24707 (17)	0.0163 (3)	0.0565 (7)
C7	0.3358 (7)	0.0974 (3)	0.1252 (4)	0.0625 (11)
H7A	0.4214	0.0577	0.1490	0.075*
C4	0.1814 (6)	0.1207 (3)	0.1977 (4)	0.0562 (11)
C9	0.3812 (7)	0.1202 (3)	0.0332 (4)	0.0574 (11)
C12	0.3662 (6)	0.1150 (2)	−0.1684 (4)	0.0504 (10)
C6	−0.1475 (7)	0.1696 (3)	0.2454 (5)	0.0654 (13)
H6A	−0.2712	0.1920	0.2277	0.079*
C5	−0.0046 (7)	0.1545 (2)	0.1731 (4)	0.0626 (11)
H5A	−0.0327	0.1670	0.1071	0.075*
C1	−0.1088 (7)	0.1517 (2)	0.3444 (3)	0.0569 (10)
C13	0.4385 (7)	0.1343 (3)	−0.2731 (4)	0.0669 (13)
H13A	0.5485	0.1725	−0.2697	0.080*
H13B	0.4898	0.0862	−0.3043	0.080*
C11	0.1829 (5)	0.0624 (2)	−0.1692 (3)	0.0540 (10)
H11A	0.1366	0.0539	−0.1015	0.065*
H11B	0.2182	0.0110	−0.1973	0.065*
O1	0.6638 (6)	0.0322 (3)	0.0197 (3)	0.0997 (14)
C3	0.2160 (7)	0.1015 (3)	0.2968 (4)	0.0635 (12)
H3A	0.3378	0.0775	0.3143	0.076*
C2	0.0755 (7)	0.1171 (3)	0.3698 (4)	0.0690 (12)
H2A	0.1036	0.1046	0.4358	0.083*
C16	0.0131 (6)	0.0998 (3)	−0.2304 (4)	0.0694 (13)
H16A	−0.1028	0.0643	−0.2316	0.083*
H16B	−0.0287	0.1495	−0.1997	0.083*
C14	0.2691 (10)	0.1683 (3)	−0.3360 (5)	0.0853 (18)
H14A	0.3159	0.1742	−0.4041	0.102*
H14B	0.2334	0.2207	−0.3112	0.102*
C15	0.0829 (9)	0.1154 (4)	−0.3347 (4)	0.0873 (17)
H15A	−0.0252	0.1409	−0.3719	0.105*
H15B	0.1140	0.0651	−0.3670	0.105*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br1	0.0827 (3)	0.0985 (4)	0.0723 (4)	0.0064 (2)	−0.0037 (3)	−0.0060 (3)
O4	0.0564 (16)	0.0396 (14)	0.0526 (15)	0.0002 (11)	−0.0015 (12)	0.0001 (14)
C8	0.046 (2)	0.043 (2)	0.0540 (17)	0.0020 (15)	−0.0062 (16)	−0.0023 (18)
C10	0.062 (2)	0.057 (3)	0.086 (4)	0.020 (2)	−0.009 (2)	−0.007 (2)
O3	0.0540 (16)	0.0653 (19)	0.069 (2)	0.0174 (14)	−0.0026 (15)	0.0004 (17)
O2	0.0606 (15)	0.0474 (16)	0.0615 (17)	0.0070 (12)	−0.0094 (14)	−0.0046 (14)
C7	0.069 (3)	0.055 (3)	0.064 (3)	0.0137 (19)	−0.015 (2)	0.001 (2)
C4	0.064 (3)	0.049 (2)	0.056 (3)	0.0003 (18)	−0.015 (2)	0.0050 (19)
C9	0.052 (2)	0.049 (2)	0.072 (3)	0.006 (2)	−0.014 (2)	0.001 (2)
C12	0.0482 (18)	0.040 (2)	0.063 (3)	0.0070 (16)	−0.0009 (19)	−0.005 (2)
C6	0.058 (2)	0.056 (3)	0.083 (4)	−0.0011 (18)	−0.019 (3)	0.010 (2)
C5	0.063 (2)	0.065 (3)	0.060 (3)	−0.0008 (19)	−0.013 (2)	0.016 (2)
C1	0.070 (2)	0.052 (2)	0.049 (2)	−0.0062 (18)	−0.011 (2)	0.0021 (19)
C13	0.075 (3)	0.059 (3)	0.067 (3)	0.010 (2)	0.019 (2)	0.007 (2)
C11	0.057 (2)	0.045 (2)	0.060 (3)	−0.0001 (15)	−0.0026 (18)	−0.004 (2)
O1	0.095 (2)	0.111 (3)	0.093 (3)	0.059 (2)	−0.022 (2)	0.002 (2)
C3	0.070 (3)	0.063 (3)	0.057 (3)	0.012 (2)	−0.017 (2)	0.002 (2)
C2	0.083 (3)	0.061 (3)	0.063 (3)	0.002 (2)	−0.029 (3)	−0.002 (2)
C16	0.058 (2)	0.074 (3)	0.076 (4)	0.005 (2)	−0.009 (2)	−0.016 (3)
C14	0.111 (4)	0.091 (4)	0.054 (3)	0.040 (3)	0.020 (3)	0.016 (3)
C15	0.091 (4)	0.112 (4)	0.059 (3)	0.031 (3)	−0.014 (3)	−0.017 (3)

Geometric parameters (Å, º)

Br1—C1	1.875 (5)	C5—H5A	0.9300
O4—C8	1.355 (5)	C1—C2	1.391 (6)
O4—C12	1.431 (5)	C13—C14	1.513 (8)
C8—O2	1.201 (5)	C13—H13A	0.9700
C8—C9	1.487 (6)	C13—H13B	0.9700
C10—O1	1.210 (6)	C11—C16	1.525 (6)
C10—O3	1.338 (6)	C11—H11A	0.9700
C10—C9	1.487 (7)	C11—H11B	0.9700
O3—C12	1.441 (5)	C3—C2	1.374 (7)
C7—C9	1.328 (7)	C3—H3A	0.9300
C7—C4	1.462 (7)	C2—H2A	0.9300
C7—H7A	0.9300	C16—C15	1.497 (7)
C4—C3	1.387 (6)	C16—H16A	0.9700
C4—C5	1.392 (6)	C16—H16B	0.9700
C12—C11	1.498 (6)	C14—C15	1.517 (9)
C12—C13	1.520 (6)	C14—H14A	0.9700
C6—C5	1.377 (8)	C14—H14B	0.9700
C6—C1	1.385 (7)	C15—H15A	0.9700
C6—H6A	0.9300	C15—H15B	0.9700
C8—O4—C12	117.6 (4)	C12—C13—H13A	109.3
O2—C8—O4	118.3 (4)	C14—C13—H13B	109.3
O2—C8—C9	125.6 (5)	C12—C13—H13B	109.3
O4—C8—C9	115.8 (4)	H13A—C13—H13B	108.0
O1—C10—O3	118.8 (5)	C12—C11—C16	110.8 (4)
O1—C10—C9	124.1 (5)	C12—C11—H11A	109.5
O3—C10—C9	117.1 (4)	C16—C11—H11A	109.5
C10—O3—C12	118.3 (4)	C12—C11—H11B	109.5
C9—C7—C4	134.4 (4)	C16—C11—H11B	109.5
C9—C7—H7A	112.8	H11A—C11—H11B	108.1
C4—C7—H7A	112.8	C2—C3—C4	121.9 (4)
C3—C4—C5	117.8 (5)	C2—C3—H3A	119.0
C3—C4—C7	117.5 (4)	C4—C3—H3A	119.0
C5—C4—C7	124.5 (5)	C3—C2—C1	119.7 (5)
C7—C9—C10	117.2 (4)	C3—C2—H2A	120.2
C7—C9—C8	126.7 (4)	C1—C2—H2A	120.2
C10—C9—C8	116.1 (5)	C15—C16—C11	110.4 (4)
O4—C12—O3	109.8 (3)	C15—C16—H16A	109.6
O4—C12—C11	111.2 (3)	C11—C16—H16A	109.6
O3—C12—C11	112.0 (3)	C15—C16—H16B	109.6
O4—C12—C13	106.5 (3)	C11—C16—H16B	109.6
O3—C12—C13	105.2 (3)	H16A—C16—H16B	108.1
C11—C12—C13	111.8 (4)	C13—C14—C15	111.8 (4)
C5—C6—C1	120.6 (4)	C13—C14—H14A	109.3
C5—C6—H6A	119.7	C15—C14—H14A	109.3
C1—C6—H6A	119.7	C13—C14—H14B	109.3
C6—C5—C4	120.8 (5)	C15—C14—H14B	109.3
C6—C5—H5A	119.6	H14A—C14—H14B	107.9
C4—C5—H5A	119.6	C16—C15—C14	111.3 (4)
C6—C1—C2	119.1 (5)	C16—C15—H15A	109.4
C6—C1—Br1	120.4 (4)	C14—C15—H15A	109.4
C2—C1—Br1	120.4 (4)	C16—C15—H15B	109.4
C14—C13—C12	111.4 (4)	C14—C15—H15B	109.4
C14—C13—H13A	109.3	H15A—C15—H15B	108.0

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5A···O2	0.93	2.45	3.004 (2)	117
C7—H7A···O1	0.93	2.40	2.812 (2)	106