Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S160053680705310X/bt2560sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S160053680705310X/bt2560Isup2.hkl |
CCDC reference: 672786
Compound (II) was prepared via a Sharpless asymmetric dihydroxylation reaction (Sharpless et al., 1988) and was obtained in >95% e.e. as determined by chiral HPLC analysis (for experimental details see Banwell et al., 2005). A magnetically stirred solution of compound (II) (25 mg, 0.09 mmol) in DCM (5 ml) maintained at 291 K was treated, in one portion, with pyridinium hydrobromide perbromide (32 mg, 0.1 mmol) and the ensuing mixture stirred for a further 10 minutes at which time TLC analysis indicated no starting material remained. Consequently, the reaction was quenched with sodium bisulfate (0.5 ml of a 1 M aqueous solution) then NaHCO3 (2 ml of a saturated solution) was added. The DCM layer was separated, and the aqueous layer extracted with DCM (2 x 5 ml). The combined organic phases were washed with brine (1 x 10 ml) then dried (Na2SO4), filtered and the filtrate concentrated under reduced pressure. The resulting material (28 mg, 0.07 mmol) in MeOH (5 ml) was treated with conc. HCl (1 drop) and the ensuing mixture was stirred magnetically at 291 K for 18 h. The methanol was then removed under reduced pressure; water (10 ml) was added to the residue and the resulting mixture extracted with ethyl acetate (3 x 10 ml). The combined organic phases were then dried (Na2SO4), filtered, and concentrated under reduced pressure. The residue thus obtained was subjected to column chromatography (silica, 19:1 v/v ethyl acetate - methanol elution) to afford, after concentration of the appropriate fractions (Rf = 0.4), a white solid. Recrystallization of this material (from methanol-DCM) afforded the title compound (I) (20 mg, 91%) as colourless crystals, m.p. 445–446 K (Found: M+., 324.0032 and 322.0053. C11H1581BrO6 and C11H1579BrO6 requires 324.0032 and 322.0052, respectively). 1H NMR (300 MHz, CD3OD) δ 7.05 (s, 1H, ArH), 5.04 (d, J 3.8 Hz, 1H), 3.89 (s, 3H), 3.80 (s, 3H), 3.75 (m, 1H), 3.60 (m, 2H); 13C NMR (75 MHz, CD3OD) δ 148.2 (C), 144.6 (C), 139.8 (C), 132.1 (C), 108.1 (C), 107.5 (C), 74.9 (CH), 72.0 (CH), 63.6 (CH2), 59.5 (OCH3), 55.4 (OCH3); νmax (NaCl)/cm-1 3365 (broad), 2938, 1594, 1495, 1410, 1314, 1176, 1097, 856.
Reflections with sinθ/λ<0.1 were rejected as unreliable as they are in the vicinity of the beam-stop shadow.
Data collection: COLLECT (Nonius, 1997); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: ORTEPII (Johnson 1976) in TEXSAN (Molecular Structure Corporation, 1997); software used to prepare material for publication: CRYSTALS (Betteridge et al., 2003).
C11H15BrO6 | Dx = 1.692 Mg m−3 |
Mr = 323.14 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, P212121 | Cell parameters from 14986 reflections |
a = 6.6461 (1) Å | θ = 2.6–27.5° |
b = 11.2214 (2) Å | µ = 3.26 mm−1 |
c = 17.0108 (4) Å | T = 200 K |
V = 1268.64 (4) Å3 | Block, colourless |
Z = 4 | 0.36 × 0.28 × 0.27 mm |
F(000) = 656 |
Nonius KappaCCD diffractometer | 2296 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.047 |
ϕ and ω scans with CCD | θmax = 27.5°, θmin = 3.0° |
Absorption correction: multi-scan (SORTAV; Blessing, 1995, 1997) | h = −8→8 |
Tmin = 0.380, Tmax = 0.415 | k = −13→14 |
26121 measured reflections | l = −22→22 |
2916 independent reflections |
Refinement on F2 | Only H-atom coordinates refined |
Least-squares matrix: full | Method, part 1, Chebychev polynomial,
(Carruthers & Watkin, 1979, Prince, 1982)
[weight] = 1.0/[A0*T0(x) + A1*T1(x) ··· + An-1]*Tn-1(x)]
where Ai are the Chebychev coefficients listed below and x = F /Fmax Method = Robust Weighting (Prince, 1982) W = [weight] * [1-(deltaF/6*sigmaF)2]2 Ai are: 20.2 30.3 18.6 8.71 1.66 |
R[F2 > 2σ(F2)] = 0.022 | (Δ/σ)max = 0.034 |
wR(F2) = 0.058 | Δρmax = 0.70 e Å−3 |
S = 0.91 | Δρmin = −0.65 e Å−3 |
2907 reflections | Extinction correction: Larson (1970), Equation 22 |
210 parameters | Extinction coefficient: 173 (9) |
44 restraints | Absolute structure: Flack (1983), 1214 Friedel pairs |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: −0.007 (9) |
Hydrogen site location: inferred from neighbouring sites |
C11H15BrO6 | V = 1268.64 (4) Å3 |
Mr = 323.14 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 6.6461 (1) Å | µ = 3.26 mm−1 |
b = 11.2214 (2) Å | T = 200 K |
c = 17.0108 (4) Å | 0.36 × 0.28 × 0.27 mm |
Nonius KappaCCD diffractometer | 2916 independent reflections |
Absorption correction: multi-scan (SORTAV; Blessing, 1995, 1997) | 2296 reflections with I > 2σ(I) |
Tmin = 0.380, Tmax = 0.415 | Rint = 0.047 |
26121 measured reflections |
R[F2 > 2σ(F2)] = 0.022 | Only H-atom coordinates refined |
wR(F2) = 0.058 | Δρmax = 0.70 e Å−3 |
S = 0.91 | Δρmin = −0.65 e Å−3 |
2907 reflections | Absolute structure: Flack (1983), 1214 Friedel pairs |
210 parameters | Absolute structure parameter: −0.007 (9) |
44 restraints |
x | y | z | Uiso*/Ueq | ||
Br7 | 0.71340 (4) | 0.68575 (2) | 0.268949 (18) | 0.0358 | |
O9 | 0.3273 (3) | 0.8058 (2) | 0.46981 (11) | 0.0372 | |
O11 | 0.0799 (3) | 0.62452 (19) | 0.41226 (11) | 0.0277 | |
O13 | 0.5555 (3) | 0.51920 (18) | 0.49792 (12) | 0.0326 | |
O14 | −0.0461 (3) | 0.97329 (16) | 0.23181 (13) | 0.0298 | |
O16 | 0.1867 (3) | 0.93279 (17) | 0.10984 (10) | 0.0286 | |
O17 | 0.5445 (3) | 0.81131 (19) | 0.12419 (11) | 0.0314 | |
C1 | 0.4695 (3) | 0.7733 (2) | 0.26163 (17) | 0.0234 | |
C2 | 0.3472 (4) | 0.7884 (2) | 0.32756 (15) | 0.0228 | |
C3 | 0.1705 (4) | 0.8547 (2) | 0.31769 (15) | 0.0238 | |
C4 | 0.1200 (4) | 0.9032 (2) | 0.24574 (14) | 0.0237 | |
C5 | 0.2422 (4) | 0.8849 (2) | 0.18035 (14) | 0.0237 | |
C6 | 0.4186 (3) | 0.8203 (2) | 0.18853 (14) | 0.0241 | |
C8 | 0.3924 (4) | 0.7314 (2) | 0.40585 (15) | 0.0232 | |
C10 | 0.2937 (4) | 0.6088 (2) | 0.41383 (13) | 0.0215 | |
C12 | 0.3465 (4) | 0.5455 (2) | 0.49012 (16) | 0.0274 | |
C15 | −0.1565 (4) | 1.0135 (3) | 0.29855 (17) | 0.0345 | |
C18 | 0.5083 (7) | 0.7077 (3) | 0.0766 (2) | 0.0545 | |
H9 | 0.415 (4) | 0.824 (3) | 0.4971 (18) | 0.0440* | |
H11 | 0.024 (5) | 0.571 (2) | 0.3902 (18) | 0.0340* | |
H13 | 0.609 (5) | 0.577 (2) | 0.514 (2) | 0.0400* | |
H16 | 0.291 (4) | 0.943 (3) | 0.0876 (18) | 0.0350* | |
H31 | 0.085 (2) | 0.8677 (11) | 0.3605 (10) | 0.0285* | |
H81 | 0.537 (3) | 0.7206 (18) | 0.4101 (12) | 0.0279* | |
H101 | 0.335 (3) | 0.5596 (17) | 0.3687 (11) | 0.0258* | |
H121 | 0.307 (3) | 0.5945 (18) | 0.5340 (11) | 0.0328* | |
H122 | 0.272 (3) | 0.4704 (16) | 0.4909 (13) | 0.0328* | |
H151 | −0.256 (3) | 1.071 (2) | 0.2799 (13) | 0.0414* | |
H152 | −0.069 (3) | 1.053 (2) | 0.3358 (13) | 0.0414* | |
H153 | −0.222 (4) | 0.9479 (18) | 0.3252 (13) | 0.0414* | |
H181 | 0.594 (4) | 0.712 (2) | 0.0322 (14) | 0.0654* | |
H182 | 0.370 (3) | 0.707 (2) | 0.0596 (17) | 0.0654* | |
H183 | 0.537 (5) | 0.6359 (19) | 0.1056 (14) | 0.0654* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br7 | 0.02523 (12) | 0.03501 (13) | 0.04712 (15) | 0.00987 (11) | 0.00413 (13) | 0.00840 (14) |
O9 | 0.0540 (14) | 0.0312 (9) | 0.0263 (9) | 0.0018 (10) | −0.0115 (8) | −0.0080 (9) |
O11 | 0.0191 (9) | 0.0343 (10) | 0.0296 (10) | −0.0032 (7) | −0.0012 (7) | −0.0022 (8) |
O13 | 0.0291 (10) | 0.0390 (11) | 0.0296 (10) | 0.0046 (8) | −0.0038 (8) | 0.0037 (9) |
O14 | 0.0279 (9) | 0.0356 (9) | 0.0260 (8) | 0.0122 (7) | 0.0002 (9) | 0.0057 (9) |
O16 | 0.0269 (10) | 0.0357 (9) | 0.0233 (9) | 0.0055 (8) | 0.0019 (8) | 0.0072 (7) |
O17 | 0.0309 (9) | 0.0312 (9) | 0.0321 (9) | 0.0015 (9) | 0.0095 (7) | 0.0030 (9) |
C1 | 0.0194 (10) | 0.0188 (9) | 0.0319 (13) | 0.0000 (8) | 0.0008 (10) | 0.0009 (10) |
C2 | 0.0237 (11) | 0.0210 (12) | 0.0238 (12) | −0.0015 (8) | −0.0043 (9) | 0.0008 (9) |
C3 | 0.0236 (14) | 0.0280 (11) | 0.0197 (11) | 0.0028 (9) | −0.0006 (9) | 0.0010 (9) |
C4 | 0.0221 (11) | 0.0226 (10) | 0.0263 (14) | 0.0031 (9) | −0.0018 (9) | 0.0019 (9) |
C5 | 0.0256 (15) | 0.0233 (10) | 0.0221 (11) | −0.0020 (9) | −0.0010 (9) | 0.0012 (9) |
C6 | 0.0242 (11) | 0.0222 (11) | 0.0260 (12) | −0.0014 (11) | 0.0049 (9) | 0.0010 (11) |
C8 | 0.0210 (12) | 0.0238 (11) | 0.0249 (13) | 0.0010 (9) | −0.0033 (9) | 0.0005 (10) |
C10 | 0.0201 (10) | 0.0226 (10) | 0.0219 (11) | 0.0003 (11) | 0.0002 (11) | −0.0009 (8) |
C12 | 0.0273 (13) | 0.0301 (13) | 0.0247 (13) | 0.0000 (9) | 0.0013 (10) | 0.0022 (10) |
C15 | 0.0348 (15) | 0.0391 (15) | 0.0296 (13) | 0.0172 (12) | 0.0033 (11) | 0.0022 (12) |
C18 | 0.073 (2) | 0.048 (2) | 0.0422 (18) | −0.0036 (17) | 0.0220 (17) | −0.0157 (15) |
Br7—C1 | 1.899 (2) | C3—C4 | 1.381 (3) |
O9—C8 | 1.438 (3) | C3—H31 | 0.933 (17) |
O9—H9 | 0.773 (18) | C4—C5 | 1.392 (4) |
O11—C10 | 1.432 (3) | C5—C6 | 1.385 (3) |
O11—H11 | 0.799 (17) | C8—C10 | 1.530 (3) |
O13—C12 | 1.426 (3) | C8—H81 | 0.972 (17) |
O13—H13 | 0.789 (18) | C10—C12 | 1.521 (4) |
O14—C4 | 1.376 (3) | C10—H101 | 0.985 (17) |
O14—C15 | 1.425 (3) | C12—H121 | 0.964 (17) |
O16—C5 | 1.365 (3) | C12—H122 | 0.977 (17) |
O16—H16 | 0.797 (17) | C15—H151 | 0.973 (17) |
O17—C6 | 1.381 (3) | C15—H152 | 0.965 (18) |
O17—C18 | 1.437 (4) | C15—H153 | 0.968 (17) |
C1—C2 | 1.395 (4) | C18—H181 | 0.948 (18) |
C1—C6 | 1.392 (4) | C18—H182 | 0.963 (18) |
C2—C3 | 1.401 (3) | C18—H183 | 0.964 (18) |
C2—C8 | 1.508 (3) | ||
Br7···O14i | 3.252 (2) | O11···O14v | 2.989 (3) |
Br7···C4i | 3.368 (2) | O13···O16i | 2.690 (3) |
Br7···C5i | 3.497 (2) | O13···O17i | 3.194 (3) |
Br7···O11ii | 3.514 (2) | O13···C3iv | 3.525 (3) |
Br7···O16i | 3.571 (2) | O14···C10vi | 3.340 (3) |
O9···O13iii | 2.724 (3) | O17···C12vii | 3.348 (3) |
O9···O11iv | 2.730 (3) | O17···C10vii | 3.566 (3) |
O11···O16v | 2.812 (3) | ||
C8—O9—H9 | 112 (3) | C2—C8—H81 | 108.4 (12) |
C10—O11—H11 | 112 (2) | O9—C8—H81 | 108.3 (12) |
C12—O13—H13 | 108 (3) | C10—C8—H81 | 107.8 (12) |
C4—O14—C15 | 117.2 (2) | C8—C10—O11 | 108.2 (2) |
C5—O16—H16 | 104 (3) | C8—C10—C12 | 113.4 (2) |
C6—O17—C18 | 113.8 (2) | O11—C10—C12 | 107.6 (2) |
Br7—C1—C2 | 120.47 (19) | C8—C10—H101 | 108.3 (12) |
Br7—C1—C6 | 117.50 (18) | O11—C10—H101 | 109.5 (12) |
C2—C1—C6 | 122.0 (2) | C12—C10—H101 | 109.8 (12) |
C1—C2—C3 | 117.2 (2) | C10—C12—O13 | 113.6 (2) |
C1—C2—C8 | 122.8 (2) | C10—C12—H121 | 109.3 (12) |
C3—C2—C8 | 119.9 (2) | O13—C12—H121 | 108.2 (13) |
C2—C3—C4 | 121.3 (2) | C10—C12—H122 | 107.3 (13) |
C2—C3—H31 | 119.8 (11) | O13—C12—H122 | 108.2 (13) |
C4—C3—H31 | 118.9 (11) | H121—C12—H122 | 110.1 (15) |
C3—C4—O14 | 124.9 (2) | O14—C15—H151 | 107.3 (13) |
C3—C4—C5 | 120.6 (2) | O14—C15—H152 | 111.0 (14) |
O14—C4—C5 | 114.5 (2) | H151—C15—H152 | 108.7 (15) |
C4—C5—O16 | 119.1 (2) | O14—C15—H153 | 111.3 (13) |
C4—C5—C6 | 119.4 (2) | H151—C15—H153 | 110.5 (15) |
O16—C5—C6 | 121.5 (2) | H152—C15—H153 | 108.0 (15) |
C1—C6—C5 | 119.6 (2) | O17—C18—H181 | 107.8 (15) |
C1—C6—O17 | 122.2 (2) | O17—C18—H182 | 109.7 (15) |
C5—C6—O17 | 118.1 (2) | H181—C18—H182 | 109.5 (16) |
C2—C8—O9 | 111.2 (2) | O17—C18—H183 | 110.8 (15) |
C2—C8—C10 | 112.0 (2) | H181—C18—H183 | 109.4 (16) |
O9—C8—C10 | 109.0 (2) | H182—C18—H183 | 109.5 (16) |
Br7—C1—C2—C3 | 179.6 (2) | O17—C6—C1—C2 | 176.3 (2) |
Br7—C1—C2—C8 | −3.8 (3) | O17—C6—C5—C4 | −175.1 (2) |
Br7—C1—C6—O17 | −4.1 (3) | C1—C2—C3—C4 | −0.1 (3) |
Br7—C1—C6—C5 | −179.9 (2) | C1—C2—C8—C10 | −90.6 (3) |
O9—C8—C2—C1 | 147.1 (2) | C1—C6—O17—C18 | 91.6 (3) |
O9—C8—C2—C3 | −36.4 (3) | C1—C6—C5—C4 | 0.9 (3) |
O9—C8—C10—O11 | 59.3 (2) | C2—C1—C6—C5 | 0.4 (3) |
O9—C8—C10—C12 | −60.0 (3) | C2—C3—C4—C5 | 1.5 (4) |
O11—C10—C8—C2 | −64.2 (3) | C2—C8—C10—C12 | 176.5 (2) |
O11—C10—C12—O13 | 177.4 (2) | C3—C2—C1—C6 | −0.8 (3) |
O13—C12—C10—C8 | −63.0 (3) | C3—C2—C8—C10 | 85.9 (3) |
O14—C4—C3—C2 | −177.2 (2) | C3—C4—O14—C15 | 10.0 (4) |
O14—C4—C5—O16 | −2.0 (3) | C3—C4—C5—C6 | −1.9 (4) |
O14—C4—C5—C6 | 177.0 (2) | C4—C3—C2—C8 | −176.9 (2) |
O16—C5—C4—C3 | 179.2 (2) | C5—C4—O14—C15 | −168.8 (2) |
O16—C5—C6—O17 | 3.8 (3) | C5—C6—O17—C18 | −92.5 (3) |
O16—C5—C6—C1 | 179.8 (2) | C6—C1—C2—C8 | 175.8 (2) |
Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) x+1, y, z; (iii) x−1/2, −y+3/2, −z+1; (iv) x+1/2, −y+3/2, −z+1; (v) −x, y−1/2, −z+1/2; (vi) −x, y+1/2, −z+1/2; (vii) −x+1, y+1/2, −z+1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
O9—H9···O11iv | 0.77 (3) | 1.98 (3) | 2.730 (3) | 164 (3) |
O11—H11···O14v | 0.80 (3) | 2.35 (3) | 2.989 (3) | 137 (3) |
O11—H11···O16v | 0.80 (3) | 2.09 (3) | 2.812 (3) | 150 (3) |
O13—H13···O9iv | 0.79 (3) | 1.98 (3) | 2.724 (3) | 158 (3) |
O16—H16···O17 | 0.80 (3) | 2.33 (3) | 2.752 (3) | 114 (3) |
O16—H16···O13vii | 0.80 (3) | 1.97 (3) | 2.690 (3) | 149 (3) |
Symmetry codes: (iv) x+1/2, −y+3/2, −z+1; (v) −x, y−1/2, −z+1/2; (vii) −x+1, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C11H15BrO6 |
Mr | 323.14 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 200 |
a, b, c (Å) | 6.6461 (1), 11.2214 (2), 17.0108 (4) |
V (Å3) | 1268.64 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 3.26 |
Crystal size (mm) | 0.36 × 0.28 × 0.27 |
Data collection | |
Diffractometer | Nonius KappaCCD diffractometer |
Absorption correction | Multi-scan (SORTAV; Blessing, 1995, 1997) |
Tmin, Tmax | 0.380, 0.415 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 26121, 2916, 2296 |
Rint | 0.047 |
(sin θ/λ)max (Å−1) | 0.650 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.022, 0.058, 0.91 |
No. of reflections | 2907 |
No. of parameters | 210 |
No. of restraints | 44 |
H-atom treatment | Only H-atom coordinates refined |
Δρmax, Δρmin (e Å−3) | 0.70, −0.65 |
Absolute structure | Flack (1983), 1214 Friedel pairs |
Absolute structure parameter | −0.007 (9) |
Computer programs: COLLECT (Nonius, 1997), DENZO/SCALEPACK (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1994), CRYSTALS (Betteridge et al., 2003), ORTEPII (Johnson 1976) in TEXSAN (Molecular Structure Corporation, 1997).
D—H···A | D—H | H···A | D···A | D—H···A |
O9—H9···O11i | 0.77 (3) | 1.98 (3) | 2.730 (3) | 164 (3) |
O11—H11···O14ii | 0.80 (3) | 2.35 (3) | 2.989 (3) | 137 (3) |
O11—H11···O16ii | 0.80 (3) | 2.09 (3) | 2.812 (3) | 150 (3) |
O13—H13···O9i | 0.79 (3) | 1.98 (3) | 2.724 (3) | 158 (3) |
O16—H16···O17 | 0.80 (3) | 2.33 (3) | 2.752 (3) | 114 (3) |
O16—H16···O13iii | 0.80 (3) | 1.97 (3) | 2.690 (3) | 149 (3) |
Symmetry codes: (i) x+1/2, −y+3/2, −z+1; (ii) −x, y−1/2, −z+1/2; (iii) −x+1, y+1/2, −z+1/2. |
In the stereoselective total synthesis of the natural product (–)-aiphanol, the absolute stereochemistry on the 1,4-dioxane ring system was unequivocally determined (Banwell et al., 2005). To achieve this the absolute stereochemistry at the stereogenic centres of the key intermediate used in the synthesis, compound (II), was determined through single-crystal X-ray analysis of its brominated derivative (I).
Compound (I) was obtained through bromination of compound (II) with pyridinium hydrobromide perbromide followed by removal of the methoxymethyl (MOM) group under acidic conditions. The so-formed white solid was recrystallized from methanol-DCM to afford pure colourless crystals.
Compound (I) is enantiomerically pure and the absolute structure of the crystal has been determined by refinement of the Flack parameter. The outcome clearly indicates the absolute configuration at C-1 and C-2 as R in each case.
All H atoms were observed in a difference electron-density map. They were then repositioned geometrically and their coordinates refined with restraints being applied to distances and bond angles. Intermolecular hydrogen-bonding interactions are observed between the O—H groups O9—H9 and O13—H13 with O11 and O9, respectively, of an adjacent molecule. Intermolecular hydrogen bonding interactions are also observed for O11—H11 with O14 and O16, and for O16—H16 with O13 and O17 of adjacent molecules.