Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270112010001/sf3168sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270112010001/sf3168Isup2.hkl | |
Portable Document Format (PDF) file https://doi.org/10.1107/S0108270112010001/sf3168sup3.pdf |
CCDC reference: 879455
To a solution of 4,6-di-O-benzyl-1,3-O-benzylidene-2-O-(4-methoxybenzyl)-myo-inositol (Gurale et al., 2011; 1.80 g, 3.16 mmol) in ethyl acetate (20 ml) was added 2-iodoxybenzoic acid (IBX; 1.77 g, 6.32 mmol) and the resulting solution refluxed for 3 h. The reaction mixture was filtered through a sintered glass funnel and the residue was washed with ethyl acetate (3 × 50 ml). The combined filtrate and washings were evaporated under reduced pressure, and the residue was dissolved in hot methanol and stored at ambient temperature. Colourless prismatic crystals of (I) were spontaneously obtained within 1 h (yield 1.70 g, 95%). Analyses: thin-layer chromatography: RF = 0.5 in 20% ethyl acetate/light petroleum; m.p. 348.8–350.5 K; IR (CHCl3, ν, cm-1): 1716; 1H NMR (CDCl3, 400 MHz, δ, p.p.m.): 7.41–7.49 (m, 2H, Ar H), 7.20–7.40 (m, 15H, Ar H), 6.83–6.88 (m, 2H, Ar H), 5.66 (s, 1H, HCO2), 4.67 (s, 2H, CH2), 4.63 (q, 4H, J = 11.8 Hz, 2 × CH2), 4.49 (m, 2H, Ins H), 4.23 (t, 1H, J = 2.0 Hz, Ins H), 4.17 (d, 2H, J = 2.5 Hz, Ins H), 3.79 (s, 3H, CH3); 13C NMR (CDCl3, 100.6 MHz, δ, p.p.m.): 201.0 (C═O), 159.3 (Carom), 137.7 (Carom), 136.6 (Carom), 129.9 (Carom), 129.7 (Carom), 129.4 (Carom), 128.4 (Carom), 128.3 (Carom), 128.1 (Carom), 127.9 (Carom), 126.2 (Carom), 113.8 (Carom), 93.9 (HCO2), 79.4 (Ins C), 73.7 (Ins C), 71.9 (CH2), 70.7 (CH2), 66.0 (Ins C), 55.2 (CH3); analysis calculated for C35H34O7: C 74.19, H 6.05%; found: C 74.36, H 6.04%. Crystallization from other common organic solvents like ethyl acetate, chloroform, dichloromethane and acetonitrile, as well as from the melt, also yielded chiral crystals spontaneously.
All H atoms were placed in geometrically idealized positions (C—H = 1.00 Å for inositol ring H atoms and atom H7, C—H = 0.95 Å for phenyl H atoms, C—H = 0.99 Å for methylene H atoms and C—H = 0.98 Å for methyl H atoms) and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C). In the absence of any significant anomalous scatterers in the molecule, the 1083 Friedel pairs were merged before the final refinement. The anisotropic displacement parameters (ADPs) for benzyl group C16–C22 were large, indicating orientational disorder. However, a reasonable model was obtained by splitting the benzyl group into two components (C16–C22 and C16'–C22') each with equal (0.5) occupancies, thus making the sum of the site-occupancy factors for the disordered atoms to unity. Furthermore, the ADPs of these group atoms were restrained to be similar using SIMU instruction. In addition, the bond length of O4—C16 and O4—C16' groups were restrained to be similar using the SADI instruction.
Data collection: SMART (Bruker, 2003); cell refinement: SMART (Bruker, 2003); data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).
C35H34O7 | F(000) = 600 |
Mr = 566.62 | Dx = 1.284 Mg m−3 |
Monoclinic, P21 | Melting point: 350 K |
Hall symbol: P 2yb | Mo Kα radiation, λ = 0.71073 Å |
a = 9.492 (8) Å | Cell parameters from 2778 reflections |
b = 9.735 (8) Å | θ = 2.2–26.8° |
c = 16.289 (13) Å | µ = 0.09 mm−1 |
β = 103.206 (12)° | T = 133 K |
V = 1465 (2) Å3 | Prism, colourless |
Z = 2 | 0.18 × 0.13 × 0.09 mm |
Bruker SMART APEX CCD area-detector diffractometer | 2741 independent reflections |
Radiation source: fine-focus sealed tube | 2503 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.047 |
ω and ϕ scans | θmax = 25.0°, θmin = 2.2° |
Absorption correction: multi-scan (SADABS; Bruker, 2003) | h = −11→11 |
Tmin = 0.984, Tmax = 0.992 | k = −11→11 |
7169 measured reflections | l = −10→19 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.073 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.138 | H-atom parameters constrained |
S = 1.26 | w = 1/[σ2(Fo2) + (0.0251P)2 + 1.6618P] where P = (Fo2 + 2Fc2)/3 |
2741 reflections | (Δ/σ)max < 0.001 |
443 parameters | Δρmax = 0.29 e Å−3 |
188 restraints | Δρmin = −0.28 e Å−3 |
C35H34O7 | V = 1465 (2) Å3 |
Mr = 566.62 | Z = 2 |
Monoclinic, P21 | Mo Kα radiation |
a = 9.492 (8) Å | µ = 0.09 mm−1 |
b = 9.735 (8) Å | T = 133 K |
c = 16.289 (13) Å | 0.18 × 0.13 × 0.09 mm |
β = 103.206 (12)° |
Bruker SMART APEX CCD area-detector diffractometer | 2741 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2003) | 2503 reflections with I > 2σ(I) |
Tmin = 0.984, Tmax = 0.992 | Rint = 0.047 |
7169 measured reflections |
R[F2 > 2σ(F2)] = 0.073 | 188 restraints |
wR(F2) = 0.138 | H-atom parameters constrained |
S = 1.26 | Δρmax = 0.29 e Å−3 |
2741 reflections | Δρmin = −0.28 e Å−3 |
443 parameters |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
O1 | 0.8474 (4) | −0.1715 (4) | 1.0546 (2) | 0.0189 (8) | |
O2 | 1.0289 (4) | −0.0858 (4) | 0.9434 (2) | 0.0193 (8) | |
O3 | 0.9249 (4) | 0.0588 (4) | 1.0729 (2) | 0.0195 (9) | |
O4 | 0.6848 (4) | 0.2010 (4) | 0.8861 (2) | 0.0228 (9) | |
O5 | 0.4902 (5) | 0.0514 (4) | 0.9894 (3) | 0.0318 (10) | |
O6 | 0.6008 (4) | −0.1214 (4) | 0.8509 (2) | 0.0204 (8) | |
O7 | 0.8701 (5) | −0.1668 (4) | 0.5423 (2) | 0.0319 (10) | |
C1 | 0.7975 (6) | −0.1528 (5) | 0.9652 (3) | 0.0181 (12) | |
H1 | 0.8132 | −0.2408 | 0.9368 | 0.022* | |
C2 | 0.8842 (5) | −0.0409 (6) | 0.9339 (3) | 0.0168 (12) | |
H2 | 0.8411 | −0.0228 | 0.8729 | 0.020* | |
C3 | 0.8713 (6) | 0.0888 (5) | 0.9849 (3) | 0.0171 (12) | |
H3 | 0.9329 | 0.1624 | 0.9684 | 0.021* | |
C4 | 0.7156 (6) | 0.1404 (6) | 0.9686 (3) | 0.0210 (12) | |
H4 | 0.7077 | 0.2121 | 1.0113 | 0.025* | |
C5 | 0.6040 (6) | 0.0271 (6) | 0.9697 (3) | 0.0217 (13) | |
C6 | 0.6362 (5) | −0.1192 (6) | 0.9406 (3) | 0.0200 (12) | |
H6 | 0.5789 | −0.1897 | 0.9636 | 0.024* | |
C7 | 0.8465 (6) | −0.0499 (6) | 1.1021 (3) | 0.0211 (13) | |
H7 | 0.7446 | −0.0203 | 1.0990 | 0.025* | |
C8 | 1.1005 (6) | −0.0236 (5) | 0.8843 (3) | 0.0209 (13) | |
H8A | 1.2041 | −0.0493 | 0.8994 | 0.025* | |
H8B | 1.0945 | 0.0775 | 0.8891 | 0.025* | |
C9 | 1.0380 (6) | −0.0646 (6) | 0.7938 (3) | 0.0198 (12) | |
C10 | 1.0336 (6) | 0.0288 (6) | 0.7281 (3) | 0.0231 (13) | |
H10 | 1.0705 | 0.1191 | 0.7403 | 0.028* | |
C11 | 0.9762 (7) | −0.0092 (6) | 0.6463 (4) | 0.0297 (15) | |
H11 | 0.9735 | 0.0557 | 0.6024 | 0.036* | |
C12 | 0.9219 (6) | −0.1405 (6) | 0.6260 (3) | 0.0201 (12) | |
C13 | 0.9261 (6) | −0.2345 (6) | 0.6903 (4) | 0.0238 (13) | |
H13 | 0.8897 | −0.3248 | 0.6778 | 0.029* | |
C14 | 0.9840 (6) | −0.1954 (6) | 0.7732 (3) | 0.0236 (13) | |
H14 | 0.9866 | −0.2604 | 0.8170 | 0.028* | |
C15 | 0.8230 (8) | −0.3025 (7) | 0.5190 (4) | 0.0386 (17) | |
H15A | 0.7385 | −0.3240 | 0.5418 | 0.058* | |
H15B | 0.9011 | −0.3673 | 0.5418 | 0.058* | |
H15C | 0.7968 | −0.3099 | 0.4574 | 0.058* | |
C16 | 0.5726 (14) | 0.3062 (14) | 0.8804 (10) | 0.031 (3) | 0.50 |
H16A | 0.6019 | 0.3739 | 0.9265 | 0.037* | 0.50 |
H16B | 0.4805 | 0.2633 | 0.8857 | 0.037* | 0.50 |
C17 | 0.553 (4) | 0.376 (3) | 0.796 (2) | 0.023 (2) | 0.50 |
C18 | 0.600 (3) | 0.509 (2) | 0.7918 (14) | 0.026 (3) | 0.50 |
H18 | 0.6435 | 0.5561 | 0.8423 | 0.031* | 0.50 |
C19 | 0.5858 (18) | 0.576 (2) | 0.7147 (10) | 0.025 (3) | 0.50 |
H19 | 0.6253 | 0.6655 | 0.7123 | 0.030* | 0.50 |
C20 | 0.515 (2) | 0.5128 (19) | 0.6437 (11) | 0.028 (3) | 0.50 |
H20 | 0.4961 | 0.5617 | 0.5918 | 0.034* | 0.50 |
C21 | 0.469 (2) | 0.3763 (16) | 0.6446 (14) | 0.025 (3) | 0.50 |
H21 | 0.4245 | 0.3299 | 0.5940 | 0.030* | 0.50 |
C22 | 0.492 (2) | 0.309 (3) | 0.7251 (11) | 0.023 (3) | 0.50 |
H22 | 0.4626 | 0.2165 | 0.7280 | 0.028* | 0.50 |
C16' | 0.5385 (11) | 0.2576 (14) | 0.8590 (9) | 0.025 (3) | 0.50 |
H16C | 0.5099 | 0.3047 | 0.9066 | 0.030* | 0.50 |
H16D | 0.4680 | 0.1835 | 0.8383 | 0.030* | 0.50 |
C17' | 0.543 (4) | 0.358 (3) | 0.790 (3) | 0.024 (2) | 0.50 |
C18' | 0.610 (3) | 0.484 (2) | 0.8077 (14) | 0.024 (3) | 0.50 |
H18' | 0.6555 | 0.5054 | 0.8644 | 0.028* | 0.50 |
C19' | 0.6131 (18) | 0.577 (2) | 0.7464 (9) | 0.026 (3) | 0.50 |
H19' | 0.6638 | 0.6612 | 0.7600 | 0.031* | 0.50 |
C20' | 0.5413 (19) | 0.5493 (17) | 0.6628 (13) | 0.027 (3) | 0.50 |
H20' | 0.5424 | 0.6160 | 0.6204 | 0.033* | 0.50 |
C21' | 0.468 (2) | 0.4245 (17) | 0.6406 (13) | 0.025 (3) | 0.50 |
H21' | 0.4177 | 0.4084 | 0.5839 | 0.030* | 0.50 |
C22' | 0.468 (2) | 0.320 (3) | 0.7046 (12) | 0.026 (3) | 0.50 |
H22' | 0.4227 | 0.2333 | 0.6916 | 0.031* | 0.50 |
C23 | 0.4499 (6) | −0.1230 (8) | 0.8143 (3) | 0.0315 (15) | |
H23A | 0.4032 | −0.0414 | 0.8328 | 0.038* | |
H23B | 0.4053 | −0.2063 | 0.8324 | 0.038* | |
C24 | 0.4288 (6) | −0.1221 (6) | 0.7195 (3) | 0.0246 (13) | |
C25 | 0.3052 (6) | −0.1812 (7) | 0.6716 (3) | 0.0294 (14) | |
H25 | 0.2361 | −0.2211 | 0.6984 | 0.035* | |
C26 | 0.2813 (6) | −0.1827 (8) | 0.5848 (4) | 0.0383 (17) | |
H26 | 0.1956 | −0.2232 | 0.5521 | 0.046* | |
C27 | 0.3822 (6) | −0.1253 (8) | 0.5451 (4) | 0.0365 (16) | |
H27 | 0.3662 | −0.1267 | 0.4854 | 0.044* | |
C28 | 0.5062 (7) | −0.0661 (8) | 0.5936 (4) | 0.0375 (17) | |
H28 | 0.5760 | −0.0267 | 0.5671 | 0.045* | |
C29 | 0.5285 (6) | −0.0644 (7) | 0.6804 (4) | 0.0288 (14) | |
H29 | 0.6134 | −0.0230 | 0.7134 | 0.035* | |
C30 | 0.9215 (6) | −0.0793 (6) | 1.1925 (3) | 0.0218 (13) | |
C31 | 1.0589 (6) | −0.1286 (6) | 1.2139 (4) | 0.0270 (13) | |
H31 | 1.1097 | −0.1469 | 1.1712 | 0.032* | |
C32 | 1.1240 (6) | −0.1521 (7) | 1.2960 (4) | 0.0346 (15) | |
H32 | 1.2206 | −0.1854 | 1.3104 | 0.041* | |
C33 | 1.0506 (7) | −0.1279 (6) | 1.3587 (4) | 0.0324 (15) | |
H33 | 1.0967 | −0.1451 | 1.4160 | 0.039* | |
C34 | 0.9112 (7) | −0.0790 (6) | 1.3384 (4) | 0.0314 (15) | |
H34 | 0.8601 | −0.0629 | 1.3812 | 0.038* | |
C35 | 0.8457 (6) | −0.0533 (6) | 1.2544 (4) | 0.0265 (13) | |
H35 | 0.7498 | −0.0182 | 1.2394 | 0.032* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.024 (2) | 0.0161 (19) | 0.0174 (18) | −0.0030 (17) | 0.0063 (16) | 0.0016 (16) |
O2 | 0.0183 (19) | 0.024 (2) | 0.0169 (19) | 0.0019 (16) | 0.0065 (15) | 0.0032 (16) |
O3 | 0.030 (2) | 0.0148 (19) | 0.0162 (19) | 0.0012 (17) | 0.0093 (16) | 0.0045 (16) |
O4 | 0.028 (2) | 0.026 (2) | 0.020 (2) | 0.0110 (18) | 0.0185 (17) | 0.0073 (18) |
O5 | 0.027 (2) | 0.044 (3) | 0.031 (2) | 0.007 (2) | 0.0183 (18) | 0.005 (2) |
O6 | 0.0188 (19) | 0.030 (2) | 0.0140 (18) | −0.0001 (18) | 0.0065 (15) | −0.0016 (17) |
O7 | 0.050 (3) | 0.031 (2) | 0.0147 (19) | −0.003 (2) | 0.0064 (18) | −0.0003 (19) |
C1 | 0.029 (3) | 0.013 (3) | 0.013 (3) | −0.003 (2) | 0.005 (2) | −0.003 (2) |
C2 | 0.011 (3) | 0.025 (3) | 0.013 (2) | 0.009 (2) | 0.000 (2) | 0.002 (2) |
C3 | 0.028 (3) | 0.016 (3) | 0.007 (2) | −0.002 (2) | 0.005 (2) | 0.002 (2) |
C4 | 0.031 (3) | 0.021 (3) | 0.014 (3) | 0.001 (3) | 0.011 (2) | 0.002 (2) |
C5 | 0.026 (3) | 0.034 (3) | 0.008 (2) | 0.008 (3) | 0.009 (2) | 0.000 (2) |
C6 | 0.020 (3) | 0.026 (3) | 0.017 (3) | −0.005 (3) | 0.008 (2) | −0.004 (2) |
C7 | 0.030 (3) | 0.022 (3) | 0.013 (3) | 0.003 (3) | 0.010 (2) | 0.003 (2) |
C8 | 0.015 (3) | 0.016 (3) | 0.034 (3) | 0.007 (2) | 0.011 (2) | 0.002 (2) |
C9 | 0.016 (3) | 0.018 (3) | 0.027 (3) | 0.000 (2) | 0.008 (2) | −0.008 (3) |
C10 | 0.032 (3) | 0.015 (3) | 0.026 (3) | −0.001 (3) | 0.014 (3) | −0.002 (2) |
C11 | 0.038 (4) | 0.029 (4) | 0.022 (3) | 0.001 (3) | 0.007 (3) | 0.014 (3) |
C12 | 0.019 (3) | 0.023 (3) | 0.019 (3) | 0.007 (3) | 0.006 (2) | 0.007 (2) |
C13 | 0.033 (3) | 0.014 (3) | 0.028 (3) | −0.006 (3) | 0.013 (3) | −0.004 (2) |
C14 | 0.028 (3) | 0.033 (3) | 0.017 (3) | 0.006 (3) | 0.018 (2) | 0.008 (3) |
C15 | 0.062 (5) | 0.034 (4) | 0.019 (3) | −0.009 (4) | 0.007 (3) | −0.008 (3) |
C16 | 0.031 (5) | 0.029 (6) | 0.035 (6) | 0.008 (5) | 0.012 (5) | 0.003 (5) |
C17 | 0.022 (4) | 0.023 (5) | 0.028 (5) | 0.013 (4) | 0.010 (4) | 0.002 (4) |
C18 | 0.029 (4) | 0.021 (5) | 0.027 (6) | 0.008 (4) | 0.006 (5) | 0.000 (4) |
C19 | 0.029 (5) | 0.019 (4) | 0.028 (6) | 0.006 (4) | 0.011 (5) | 0.000 (6) |
C20 | 0.034 (5) | 0.021 (6) | 0.029 (5) | 0.009 (5) | 0.006 (4) | 0.005 (5) |
C21 | 0.024 (4) | 0.023 (6) | 0.030 (5) | 0.007 (5) | 0.012 (4) | 0.006 (6) |
C22 | 0.020 (5) | 0.022 (5) | 0.030 (6) | 0.009 (4) | 0.014 (5) | 0.005 (5) |
C16' | 0.029 (5) | 0.025 (6) | 0.026 (6) | 0.008 (5) | 0.015 (4) | 0.007 (5) |
C17' | 0.023 (4) | 0.023 (5) | 0.029 (5) | 0.012 (4) | 0.012 (4) | 0.004 (4) |
C18' | 0.026 (5) | 0.022 (6) | 0.026 (6) | 0.013 (5) | 0.011 (5) | −0.002 (5) |
C19' | 0.026 (5) | 0.024 (5) | 0.027 (6) | 0.008 (4) | 0.003 (5) | 0.002 (5) |
C20' | 0.029 (5) | 0.023 (6) | 0.029 (6) | 0.007 (5) | 0.003 (5) | 0.004 (5) |
C21' | 0.026 (4) | 0.025 (6) | 0.026 (4) | 0.007 (6) | 0.011 (4) | −0.003 (6) |
C22' | 0.025 (5) | 0.025 (5) | 0.027 (5) | 0.007 (4) | 0.006 (4) | 0.006 (5) |
C23 | 0.015 (3) | 0.051 (4) | 0.029 (3) | −0.001 (3) | 0.006 (2) | −0.008 (3) |
C24 | 0.024 (3) | 0.029 (3) | 0.023 (3) | 0.007 (3) | 0.009 (2) | −0.002 (3) |
C25 | 0.015 (3) | 0.051 (4) | 0.023 (3) | −0.001 (3) | 0.006 (2) | 0.003 (3) |
C26 | 0.015 (3) | 0.075 (5) | 0.022 (3) | 0.006 (3) | −0.003 (2) | 0.000 (3) |
C27 | 0.033 (3) | 0.063 (5) | 0.014 (3) | 0.007 (4) | 0.007 (2) | 0.004 (3) |
C28 | 0.035 (4) | 0.054 (4) | 0.028 (3) | 0.006 (4) | 0.016 (3) | 0.008 (3) |
C29 | 0.026 (3) | 0.033 (3) | 0.027 (3) | −0.005 (3) | 0.006 (3) | 0.004 (3) |
C30 | 0.031 (3) | 0.017 (3) | 0.015 (3) | −0.005 (3) | −0.001 (2) | 0.008 (2) |
C31 | 0.025 (3) | 0.029 (3) | 0.030 (3) | −0.006 (3) | 0.013 (3) | 0.004 (3) |
C32 | 0.020 (3) | 0.033 (4) | 0.046 (4) | 0.001 (3) | −0.002 (3) | 0.011 (3) |
C33 | 0.037 (4) | 0.031 (3) | 0.021 (3) | −0.009 (3) | −0.010 (3) | 0.016 (3) |
C34 | 0.046 (4) | 0.032 (4) | 0.020 (3) | −0.021 (3) | 0.016 (3) | −0.007 (3) |
C35 | 0.019 (3) | 0.024 (3) | 0.038 (3) | 0.000 (3) | 0.008 (3) | −0.002 (3) |
O1—C7 | 1.416 (7) | C18—C19 | 1.40 (2) |
O1—C1 | 1.437 (6) | C18—H18 | 0.9500 |
O2—C2 | 1.416 (6) | C19—C20 | 1.35 (2) |
O2—C8 | 1.434 (6) | C19—H19 | 0.9500 |
O3—C7 | 1.436 (6) | C20—C21 | 1.40 (2) |
O3—C3 | 1.437 (6) | C20—H20 | 0.9500 |
O4—C4 | 1.436 (6) | C21—C22 | 1.44 (2) |
O4—C16 | 1.465 (9) | C21—H21 | 0.9500 |
O4—C16' | 1.465 (9) | C22—H22 | 0.9500 |
O5—C5 | 1.218 (6) | C16'—C17' | 1.50 (4) |
O6—C23 | 1.420 (6) | C16'—H16C | 0.9900 |
O6—C6 | 1.424 (6) | C16'—H16D | 0.9900 |
O7—C12 | 1.364 (7) | C17'—C18' | 1.39 (3) |
O7—C15 | 1.418 (8) | C17'—C22' | 1.45 (4) |
C1—C2 | 1.521 (7) | C18'—C19' | 1.35 (2) |
C1—C6 | 1.527 (7) | C18'—H18' | 0.9500 |
C1—H1 | 1.0000 | C19'—C20' | 1.40 (2) |
C2—C3 | 1.532 (7) | C19'—H19' | 0.9500 |
C2—H2 | 1.0000 | C20'—C21' | 1.41 (2) |
C3—C4 | 1.525 (8) | C20'—H20' | 0.9500 |
C3—H3 | 1.0000 | C21'—C22' | 1.46 (3) |
C4—C5 | 1.532 (8) | C21'—H21' | 0.9500 |
C4—H4 | 1.0000 | C22'—H22' | 0.9500 |
C5—C6 | 1.553 (8) | C23—C24 | 1.511 (7) |
C6—H6 | 1.0000 | C23—H23A | 0.9900 |
C7—C30 | 1.508 (7) | C23—H23B | 0.9900 |
C7—H7 | 1.0000 | C24—C29 | 1.376 (8) |
C8—C9 | 1.512 (8) | C24—C25 | 1.378 (8) |
C8—H8A | 0.9900 | C25—C26 | 1.379 (8) |
C8—H8B | 0.9900 | C25—H25 | 0.9500 |
C9—C14 | 1.385 (8) | C26—C27 | 1.389 (8) |
C9—C10 | 1.397 (8) | C26—H26 | 0.9500 |
C10—C11 | 1.371 (8) | C27—C28 | 1.384 (9) |
C10—H10 | 0.9500 | C27—H27 | 0.9500 |
C11—C12 | 1.389 (8) | C28—C29 | 1.381 (8) |
C11—H11 | 0.9500 | C28—H28 | 0.9500 |
C12—C13 | 1.384 (8) | C29—H29 | 0.9500 |
C13—C14 | 1.390 (8) | C30—C31 | 1.359 (8) |
C13—H13 | 0.9500 | C30—C35 | 1.389 (8) |
C14—H14 | 0.9500 | C31—C32 | 1.358 (8) |
C15—H15A | 0.9800 | C31—H31 | 0.9500 |
C15—H15B | 0.9800 | C32—C33 | 1.382 (9) |
C15—H15C | 0.9800 | C32—H32 | 0.9500 |
C16—C17 | 1.50 (4) | C33—C34 | 1.374 (9) |
C16—H16A | 0.9900 | C33—H33 | 0.9500 |
C16—H16B | 0.9900 | C34—C35 | 1.390 (8) |
C17—C22 | 1.34 (3) | C34—H34 | 0.9500 |
C17—C18 | 1.37 (3) | C35—H35 | 0.9500 |
C7—O1—C1 | 114.0 (4) | C22—C17—C16 | 120 (2) |
C2—O2—C8 | 113.2 (4) | C18—C17—C16 | 120 (3) |
C7—O3—C3 | 112.9 (4) | C17—C18—C19 | 122 (3) |
C4—O4—C16 | 109.6 (7) | C17—C18—H18 | 119.2 |
C4—O4—C16' | 114.4 (7) | C19—C18—H18 | 119.2 |
C23—O6—C6 | 114.2 (4) | C20—C19—C18 | 119.0 (18) |
C12—O7—C15 | 117.5 (4) | C20—C19—H19 | 120.5 |
O1—C1—C2 | 110.6 (4) | C18—C19—H19 | 120.5 |
O1—C1—C6 | 111.8 (4) | C19—C20—C21 | 121.4 (18) |
C2—C1—C6 | 110.2 (4) | C19—C20—H20 | 119.3 |
O1—C1—H1 | 108.0 | C21—C20—H20 | 119.3 |
C2—C1—H1 | 108.0 | C20—C21—C22 | 117 (2) |
C6—C1—H1 | 108.0 | C20—C21—H21 | 121.4 |
O2—C2—C1 | 109.1 (4) | C22—C21—H21 | 121.4 |
O2—C2—C3 | 113.0 (4) | C17—C22—C21 | 121 (3) |
C1—C2—C3 | 107.0 (4) | C17—C22—H22 | 119.5 |
O2—C2—H2 | 109.2 | C21—C22—H22 | 119.5 |
C1—C2—H2 | 109.2 | O4—C16'—C17' | 106.5 (16) |
C3—C2—H2 | 109.2 | O4—C16'—H16C | 110.4 |
O3—C3—C4 | 110.4 (4) | C17'—C16'—H16C | 110.4 |
O3—C3—C2 | 108.7 (4) | O4—C16'—H16D | 110.4 |
C4—C3—C2 | 111.8 (4) | C17'—C16'—H16D | 110.4 |
O3—C3—H3 | 108.6 | H16C—C16'—H16D | 108.6 |
C4—C3—H3 | 108.6 | C18'—C17'—C22' | 122 (3) |
C2—C3—H3 | 108.6 | C18'—C17'—C16' | 120 (3) |
O4—C4—C3 | 106.3 (4) | C22'—C17'—C16' | 118 (2) |
O4—C4—C5 | 108.3 (4) | C19'—C18'—C17' | 122 (3) |
C3—C4—C5 | 114.0 (4) | C19'—C18'—H18' | 119.2 |
O4—C4—H4 | 109.4 | C17'—C18'—H18' | 119.2 |
C3—C4—H4 | 109.4 | C18'—C19'—C20' | 119.9 (19) |
C5—C4—H4 | 109.4 | C18'—C19'—H19' | 120.0 |
O5—C5—C4 | 121.4 (5) | C20'—C19'—H19' | 120.0 |
O5—C5—C6 | 120.4 (5) | C19'—C20'—C21' | 121.2 (18) |
C4—C5—C6 | 118.1 (4) | C19'—C20'—H20' | 119.4 |
O6—C6—C1 | 104.6 (4) | C21'—C20'—H20' | 119.4 |
O6—C6—C5 | 108.1 (4) | C20'—C21'—C22' | 120 (2) |
C1—C6—C5 | 111.9 (4) | C20'—C21'—H21' | 120.0 |
O6—C6—H6 | 110.7 | C22'—C21'—H21' | 120.0 |
C1—C6—H6 | 110.7 | C17'—C22'—C21' | 115 (3) |
C5—C6—H6 | 110.7 | C17'—C22'—H22' | 122.3 |
O1—C7—O3 | 111.5 (4) | C21'—C22'—H22' | 122.3 |
O1—C7—C30 | 108.3 (4) | O6—C23—C24 | 108.3 (4) |
O3—C7—C30 | 107.4 (4) | O6—C23—H23A | 110.0 |
O1—C7—H7 | 109.8 | C24—C23—H23A | 110.0 |
O3—C7—H7 | 109.8 | O6—C23—H23B | 110.0 |
C30—C7—H7 | 109.8 | C24—C23—H23B | 110.0 |
O2—C8—C9 | 113.8 (4) | H23A—C23—H23B | 108.4 |
O2—C8—H8A | 108.8 | C29—C24—C25 | 119.7 (5) |
C9—C8—H8A | 108.8 | C29—C24—C23 | 122.0 (5) |
O2—C8—H8B | 108.8 | C25—C24—C23 | 118.3 (5) |
C9—C8—H8B | 108.8 | C24—C25—C26 | 120.3 (5) |
H8A—C8—H8B | 107.7 | C24—C25—H25 | 119.9 |
C14—C9—C10 | 117.9 (5) | C26—C25—H25 | 119.9 |
C14—C9—C8 | 121.4 (5) | C25—C26—C27 | 120.2 (6) |
C10—C9—C8 | 120.7 (5) | C25—C26—H26 | 119.9 |
C11—C10—C9 | 120.3 (5) | C27—C26—H26 | 119.9 |
C11—C10—H10 | 119.8 | C28—C27—C26 | 119.3 (5) |
C9—C10—H10 | 119.8 | C28—C27—H27 | 120.4 |
C10—C11—C12 | 121.5 (5) | C26—C27—H27 | 120.4 |
C10—C11—H11 | 119.2 | C29—C28—C27 | 120.0 (6) |
C12—C11—H11 | 119.2 | C29—C28—H28 | 120.0 |
O7—C12—C13 | 125.0 (5) | C27—C28—H28 | 120.0 |
O7—C12—C11 | 116.1 (5) | C24—C29—C28 | 120.5 (6) |
C13—C12—C11 | 118.9 (5) | C24—C29—H29 | 119.7 |
C12—C13—C14 | 119.4 (5) | C28—C29—H29 | 119.7 |
C12—C13—H13 | 120.3 | C31—C30—C35 | 120.3 (5) |
C14—C13—H13 | 120.3 | C31—C30—C7 | 121.9 (5) |
C9—C14—C13 | 122.0 (5) | C35—C30—C7 | 117.8 (5) |
C9—C14—H14 | 119.0 | C32—C31—C30 | 120.5 (5) |
C13—C14—H14 | 119.0 | C32—C31—H31 | 119.8 |
O7—C15—H15A | 109.5 | C30—C31—H31 | 119.8 |
O7—C15—H15B | 109.5 | C31—C32—C33 | 120.4 (6) |
H15A—C15—H15B | 109.5 | C31—C32—H32 | 119.8 |
O7—C15—H15C | 109.5 | C33—C32—H32 | 119.8 |
H15A—C15—H15C | 109.5 | C34—C33—C32 | 120.1 (5) |
H15B—C15—H15C | 109.5 | C34—C33—H33 | 119.9 |
O4—C16—C17 | 108.1 (15) | C32—C33—H33 | 119.9 |
O4—C16—H16A | 110.1 | C33—C34—C35 | 119.3 (5) |
C17—C16—H16A | 110.1 | C33—C34—H34 | 120.3 |
O4—C16—H16B | 110.1 | C35—C34—H34 | 120.3 |
C17—C16—H16B | 110.1 | C30—C35—C34 | 119.5 (5) |
H16A—C16—H16B | 108.4 | C30—C35—H35 | 120.3 |
C22—C17—C18 | 119 (4) | C34—C35—H35 | 120.3 |
C7—O1—C1—C2 | 55.2 (5) | C11—C12—C13—C14 | 0.1 (8) |
C7—O1—C1—C6 | −68.0 (5) | C10—C9—C14—C13 | −0.3 (8) |
C8—O2—C2—C1 | 153.0 (4) | C8—C9—C14—C13 | 179.9 (5) |
C8—O2—C2—C3 | −88.1 (5) | C12—C13—C14—C9 | 0.0 (8) |
O1—C1—C2—O2 | 66.5 (5) | C4—O4—C16—C17 | 174.8 (13) |
C6—C1—C2—O2 | −169.4 (4) | C16'—O4—C16—C17 | −79 (3) |
O1—C1—C2—C3 | −56.0 (5) | O4—C16—C17—C22 | 70 (3) |
C6—C1—C2—C3 | 68.1 (5) | O4—C16—C17—C18 | −109 (3) |
C7—O3—C3—C4 | 63.2 (5) | C22—C17—C18—C19 | 0 (4) |
C7—O3—C3—C2 | −59.7 (5) | C16—C17—C18—C19 | 179 (2) |
O2—C2—C3—O3 | −61.9 (5) | C17—C18—C19—C20 | 5 (3) |
C1—C2—C3—O3 | 58.2 (5) | C18—C19—C20—C21 | −7 (3) |
O2—C2—C3—C4 | 176.0 (4) | C19—C20—C21—C22 | 4 (3) |
C1—C2—C3—C4 | −63.9 (5) | C18—C17—C22—C21 | −3 (4) |
C16—O4—C4—C3 | −153.4 (7) | C16—C17—C22—C21 | 178 (2) |
C16'—O4—C4—C3 | −179.7 (7) | C20—C21—C22—C17 | 1 (3) |
C16—O4—C4—C5 | 83.8 (8) | C4—O4—C16'—C17' | 160.0 (12) |
C16'—O4—C4—C5 | 57.4 (8) | C16—O4—C16'—C17' | 76 (3) |
O3—C3—C4—O4 | 165.1 (4) | O4—C16'—C17'—C18' | −74 (3) |
C2—C3—C4—O4 | −73.8 (5) | O4—C16'—C17'—C22' | 109 (3) |
O3—C3—C4—C5 | −75.7 (5) | C22'—C17'—C18'—C19' | −2 (4) |
C2—C3—C4—C5 | 45.4 (6) | C16'—C17'—C18'—C19' | −179 (2) |
O4—C4—C5—O5 | −90.0 (6) | C17'—C18'—C19'—C20' | 3 (3) |
C3—C4—C5—O5 | 151.9 (5) | C18'—C19'—C20'—C21' | −1 (3) |
O4—C4—C5—C6 | 87.0 (5) | C19'—C20'—C21'—C22' | −2 (3) |
C3—C4—C5—C6 | −31.1 (6) | C18'—C17'—C22'—C21' | −1 (4) |
C23—O6—C6—C1 | 166.7 (5) | C16'—C17'—C22'—C21' | 176 (2) |
C23—O6—C6—C5 | −74.0 (6) | C20'—C21'—C22'—C17' | 2 (3) |
O1—C1—C6—O6 | −172.8 (4) | C6—O6—C23—C24 | 178.8 (5) |
C2—C1—C6—O6 | 63.8 (5) | O6—C23—C24—C29 | −27.8 (8) |
O1—C1—C6—C5 | 70.4 (5) | O6—C23—C24—C25 | 152.3 (6) |
C2—C1—C6—C5 | −53.0 (5) | C29—C24—C25—C26 | 0.0 (10) |
O5—C5—C6—O6 | 97.0 (5) | C23—C24—C25—C26 | 179.9 (6) |
C4—C5—C6—O6 | −80.0 (6) | C24—C25—C26—C27 | 0.4 (11) |
O5—C5—C6—C1 | −148.3 (5) | C25—C26—C27—C28 | −0.3 (11) |
C4—C5—C6—C1 | 34.7 (6) | C26—C27—C28—C29 | −0.1 (10) |
C1—O1—C7—O3 | −53.7 (6) | C25—C24—C29—C28 | −0.5 (10) |
C1—O1—C7—C30 | −171.7 (4) | C23—C24—C29—C28 | 179.6 (6) |
C3—O3—C7—O1 | 56.5 (5) | C27—C28—C29—C24 | 0.5 (10) |
C3—O3—C7—C30 | 175.1 (4) | O1—C7—C30—C31 | 56.3 (7) |
C2—O2—C8—C9 | −66.3 (5) | O3—C7—C30—C31 | −64.3 (6) |
O2—C8—C9—C14 | −34.9 (7) | O1—C7—C30—C35 | −124.1 (5) |
O2—C8—C9—C10 | 145.3 (5) | O3—C7—C30—C35 | 115.3 (5) |
C14—C9—C10—C11 | 0.5 (8) | C35—C30—C31—C32 | −0.5 (9) |
C8—C9—C10—C11 | −179.8 (5) | C7—C30—C31—C32 | 179.0 (6) |
C9—C10—C11—C12 | −0.4 (9) | C30—C31—C32—C33 | 0.9 (10) |
C15—O7—C12—C13 | −3.0 (8) | C31—C32—C33—C34 | −0.4 (10) |
C15—O7—C12—C11 | 175.8 (5) | C32—C33—C34—C35 | −0.5 (9) |
C10—C11—C12—O7 | −178.8 (5) | C31—C30—C35—C34 | −0.4 (8) |
C10—C11—C12—C13 | 0.1 (8) | C7—C30—C35—C34 | −180.0 (5) |
O7—C12—C13—C14 | 178.9 (5) | C33—C34—C35—C30 | 0.9 (9) |
D—H···A | D—H | H···A | D···A | D—H···A |
C8—H8B···O1i | 0.99 | 2.62 | 3.572 (7) | 160 |
C10—H10···Cg2i | 0.95 | 2.76 | 3.588 (7) | 146 |
C14—H14···O3ii | 0.95 | 2.52 | 3.430 (7) | 161 |
C16—H16A···O5iii | 0.99 | 2.49 | 3.336 (14) | 144 |
Symmetry codes: (i) −x+2, y+1/2, −z+2; (ii) −x+2, y−1/2, −z+2; (iii) −x+1, y+1/2, −z+2. |
Experimental details
Crystal data | |
Chemical formula | C35H34O7 |
Mr | 566.62 |
Crystal system, space group | Monoclinic, P21 |
Temperature (K) | 133 |
a, b, c (Å) | 9.492 (8), 9.735 (8), 16.289 (13) |
β (°) | 103.206 (12) |
V (Å3) | 1465 (2) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.18 × 0.13 × 0.09 |
Data collection | |
Diffractometer | Bruker SMART APEX CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2003) |
Tmin, Tmax | 0.984, 0.992 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7169, 2741, 2503 |
Rint | 0.047 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.073, 0.138, 1.26 |
No. of reflections | 2741 |
No. of parameters | 443 |
No. of restraints | 188 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.29, −0.28 |
Computer programs: SMART (Bruker, 2003), SAINT (Bruker, 2003), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).
D—H···A | D—H | H···A | D···A | D—H···A |
C8—H8B···O1i | 0.99 | 2.62 | 3.572 (7) | 160 |
C10—H10···Cg2i | 0.95 | 2.76 | 3.588 (7) | 146 |
C14—H14···O3ii | 0.95 | 2.52 | 3.430 (7) | 161 |
C16—H16A···O5iii | 0.99 | 2.49 | 3.336 (14) | 144 |
Symmetry codes: (i) −x+2, y+1/2, −z+2; (ii) −x+2, y−1/2, −z+2; (iii) −x+1, y+1/2, −z+2. |
Among the various noncovalent interactions (Desiraju, 1989) which govern the molecular arrangement in crystals, those involving the less acidic C—H group, e.g. C—H···O, C—H···π, C—H···N, C—H···X (X = F, Cl, Br), have been scrutinized intensely over the past 20–30 years (Desiraju & Steiner, 1999; Hobza & Havlas, 2000; Scheiner, 2005). Their role in molecular recognition, crystal packing and polymorphic modifications is well established in either the presence (Gonnade et al., 2008; Krishnaswamy et al., 2009) or absence (Gonnade et al., 2010) of relatively strong conventional hydrogen-bonding interactions. O-Protected myo-inositol derivatives (Sureshan et al., 2003) are important intermediates for the preparation of biologically relevant phosphoinositols. These molecules, which lack functional groups capable of forming conventional hydrogen bonds, provide opportunities to study the role of weaker noncovalent interactions of similar energies in molecular aggregation. Encouraged by the frequent polymorphic (Gonnade et al., 2004, 2005, 2008, 2010; Bhosekar et al., 2005; Manoj et al., 2009) and solvatomorphic (Sureshan et al., 2001; Gonnade et al., 2004; Manoj et al., 2006, 2012; Krishnaswamy et al., 2010) behaviour exhibited by myo-inositol derivatives; the title compound, (I), was also screened for the same property. We reported previously the role of C—H···O interactions in directing the molecular aggregation of a meso molecule, leading to the formation of chiral crystals under kinetic crystallization conditions (Gonnade et al., 2004). We report here another such occurrence, where crystallization of the meso-ketone (I) under a variety of conditions and solvents yielded chiral crystals belonging to the monoclinic space group P21 with one molecule in the asymmetric unit. Molecules of (I) form a helical chain along the b axis, linked via C—H···O and C—H···π interactions comprising polar groups clustering along the helical axis, whereas the nonpolar groups protrude perpendicular to the helical axis. Surprisingly, these neighbouring chains are loosely held along the c axis via relatively uncommon C—H···H—C short contacts (Bhosekar et al., 2005).
The conformation of the molecule of (I) as observed in the crystal structure reveals a slight deviation of the inositol ring from a chair conformation, perhaps due to the presence of a planar carbonyl group at the C5 position. However, the C1–C3/O3/C7/O1 acetal ring adopts a regular chair conformation (Fig. 1). All the benzyl groups adopt an extended conformation, pointing in the same direction but away from the fourth phenyl ring. This results in sandwiching of the hydrophilic inositol ring between hydrophobic benzene rings and facilitates the formation of a short intramolecular C2—H2···O6 hydrogen bond [H2···O6 = 2.43 Å, C2···O6 = 2.835 (7) Å and C2—H2···O6 = 104°].
Molecules of (I) form a helical assembly across the crystallographic twofold screw axis via one C—H···π and two C—H···O interactions exclusively involving the 4-methoxybenzyl (PMB) group (Fig. 2). Methylene atom C8 and phenyl atom C14 of the PMB group are involved in C—H···O contacts with atoms O1 and O3, respectively (Table 1). The latter contact is shorter than the former, whereas the angles of approach in both cases are similar. This arrangement also brings the phenyl C10—H10 group of the PMB closer to the edge atoms C31, C32 and C33 of the acetal phenyl ring, rather than pointing towards the centre of the π-cloud, generating an off-centred C—H···π contact [C10—H10···.Cg2i; Cg2 is the centroid of the C30–C35 ring [Please check added text]; Table 1; symmetry code: (ii) -x + 2, y + 1/2, -z + 2]. This helical arrangement brings polar segments of neighbouring molecules into close association, creating a hydrophilic layer between the hydrophobic layers formed by the phenyl rings (see Supplementary materials for a space-filling model).
Neighbouring helices diagonal to the ac plane are held together via another relatively long but linear C—H···O contact involving carbonyl atom O5 and the methylene C16 group of the benzyl group [C16—H16A···O5iii; Table 1; symmetry code: (iii) -x + 1, y + 1/2, -z + 2], thus generating a discrete packing of the helices throughout the crystal structure (Fig. 3). Viewed down the c axis, the molecular packing reveals the association of neighbouring unit-translated helices via hydrophobic forces; a somewhat uncommon edge-to-edge C—H···H—C contact [C33—H33···H26—C26iv, with H···H = 2.31 Å, C33···H26 = 3.254 Å and C16—H16A···O5 = 171° [not in this contact]; symmetry code: (iv) x + 1, y, z + 1] joins adjacent helical chains (Fig. 4). Therefore, the cohesion of two-dimensional layers in the bc plane seems to be only via short H···H contacts (although just at the boundary of the sum of the van der Waals radii of two H atoms, 2.35 Å; [Standard reference?]), termed `dihydrogen bonds' or `dihydrogen interactions' (Echeverría et al., 2011; Crabtree et al., 1996; Crabtree, 1998; Custelcean & Jackson, 2001; Wang et al., 2004). It is noteworthy that there are no significant aromatic π–π or C—H···π contacts between phenyl rings of adjacent helical chains, although they are clustered together.
The computation of lattice energies (using the Oprop module of the OPIX program suite; Gavezzotti, 2007) by summation of atom–atom pair-wise potential energies described by the UNI force field (Filippini & Gavezzotti, 1993; Gavezzotti & Filippini, 1994) gave a value of -263.1 kJ mol-1. The intermolecular interaction energies for C10—H10···O1 and H···H contacts were also estimated, giving values of -17.4 and 6.0 kJ mol-1, respectively, suggesting that the former contact is attractive and the latter repulsive. However, an estimation of the intermolecular potentials [the sum of Coulombic, polarization, dispersion and repulsion terms, as defined in the PIXEL method and implemented in the program Mercury (Macrae et al., 2008)], gives the overall contribution from all the intermolecular forces (including van der Waals interactions) at the interface of the two helical chains (linked by H···H contact) in the bc plane enveloped by hydrophobic groups of -3.8 kJ mol-1. This suggests that, although the H···H contact is repulsive, the other forces contribute to this bridging and thence to the overall stability of the structure. The energies of the other weak interactions such as C—H···π could not be computed separately. However, using UNI force-field calculations, approximate energies for the intermolecular potentials were estimated. The intermolecular potential associated with two neighbouring molecules involved in helical chain formation is -85.1 kJ mol-1, with major contributions from C—H···O (C14—H14···O3 and C6—H8B···O1) and C—H···π (C10—H10···π) interactions and other van der Waals forces.
The intermolecular contacts in the crystal structure of (I) were quantified via Hirshfeld surface analysis (McKinnon et al., 2004; Spackman & McKinnon, 2002) using CrystalExplorer (Wolff et al.., 2007). Hirshfeld surfaces are a novel tool for the visualization and understanding of intermolecular interactions (McKinnon et al., 2007; Munshi et al., 2008; Hathwar et al., 2010). In the present study, the contacts responsible for the chiral crystal packing in (I) [C—H···O, C—H···π, H···H and others (O···O, C···C)] were evaluated with respect to their contribution to the overall stability of the crystal structure. The percentage contributions of these interactions to the relative Hirshfeld surface areas reveal noticeable involvement of C—H···π (24.8%) and C—H···O (17.7%), whereas a significant contribution comes from H···H contacts (56%), because of the considerable engagement of the hydrophobic groups in the molecular aggregation (see Supplementary materials for figures). However, it must be noted that these percentage contributions do not differentiate between close and distant contacts. The major C—H···O, C—H···π and H···H contacts are highlighted by conventional mapping of dnorm on molecular Hirshfeld surfaces (Fig. 5). The dark spots (red in the electronic version of the paper) on the left and right surfaces of the plot are due to C—H···O and C—H···π interactions, while that on the top is from an H···H contact.
In conclusion, the spontaneous generation of chirality of an achiral molecule solely by topology of weak interactions, as observed in the present case, is an enigmatic phenomenon which continues to fascinate crystal engineers and supramolecular chemists. Deeper insight into this phenomenon, especially in crystals formed from complex molecules, could be of value in designing unconventional methods for asymmetric synthesis.