organic compounds
R,3R,4S)-3,4-bis(acetyloxy)-5-iodo-3,4-dihydro-2H-pyran-2-yl]methyl acetate
of [(2aDepartmento de Química, Universidade Federal de São Carlos, 13565-905 São Carlos, SP, Brazil, bDepartmento de Física, Universidade Federal de São Carlos, 13565-905 São Carlos, SP, Brazil, cDepartamento de Farmácia, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo-SP, Brazil, dInstituto de Química, Universidade de São Paulo, São Paulo-SP, Brazil, and eDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: julio@power.ufscar.br
In the title compound, C12H15IO7, the 3,4-dihydro-2H-pyran ring is in a distorted half-boat conformation with the atom bearing the acetyloxy group adjacent to the C atom bearing the methylacetate group lying 0.633 (6) Å above the plane of the remaining ring atoms (r.m.s. deviation = 0.0907 Å). In the crystal, molecules are linked into a supramolecular chain along the a axis through two C—H⋯O interactions to the same acceptor carbonyl O atom; these chains pack with no specific intermolecular interactions between them.
CCDC reference: 1035669
1. Related literature
For the structure of the unsubstituted parent compound, determined three times, and having a distorted half-boat conformation, see: Vangehr et al. (1979); Krajewski et al. (1979); Voelter et al. (1981).
2. Experimental
2.1. Crystal data
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Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SIR (Burla et al., 2014; program(s) used to refine structure: SHELXL2014 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: MarvinSketch (ChemAxon, 2010) and publCIF (Westrip, 2010).
Supporting information
CCDC reference: 1035669
https://doi.org/10.1107/S205698901402564X/hb7323sup1.cif
contains datablocks I, New_Global_Publ_Block. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S205698901402564X/hb7323Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S205698901402564X/hb7323Isup3.cml
To a solution of 3,4,6-tri-oxoacetyl-D-Glucal (3 mmol) in acetonitrile (9 mL) at 373 K under a N2 atmosphere was added N-iodosuccinimide (3.6 mmol) and silver nitrate (0.6 mmol) as catalyst followed by stirring for 4 h. After consumption of the starting material (TLC monitoring), the reaction mixture was filtered through a sintered funnel (using Celite) and the filtrate was then evaporated giving a crude product which was purified by silica gel
(20-30% of EtOAc/hexane) to obtain the title compound. Suitable crystals were obtained by keeping the EtOAc solution of the product at 277 K for 48 h.1H NMR (CDCl3, 300 MHz): δ 6.73 (s, 1H), 5.44 (d, J = 5.1 Hz, 1H), 5.18 (dd, J = 5.1, 7.0 Hz, 1>H), 4.37-4.30 (m, 2H), 4.08-4.18 (m, 1H), 2.09 (s, 3H), 2.05 (s, 3H), 2.04 (s, 3H). 13C NMR (CDCl3, 75 MHz) δ = 170.5, 170.3, 169.4, 149.4, 74.0, 70.6, 67.6, 66.3, 61.0, 20.9, 20.8, 20.7 ppm. HRMS: calcd. for C12H15IO7 [M + H]+ 397.9862; found: 397.9863.
Carbon-bound H-atoms were placed in calculated positions (C—H = 0.93 to 0.98 Å) and were included in the
in the riding model approximation, with Uiso(H) = 1.2–1.5Ueq(C).The 3,4-dihydro-2H-pyran ring in the title compound, Fig. 1, is in a distorted half-boat conformation as reflected in the conformational parameters: the puckering amplitude (Q) = 0.497 (5) Å, θ = 52.6 (6)° and φ = 268.6 (7)°. In this conformation, the C4 atom lies 0.633 (6) Å above the plane of the remaining ring atoms which have a r.m.s. of 0.0907 Å. The substituents at the C3 and C4 sites occupy equatorial positions while that at atom C5 is bisectional. The of the unsubstituted parent compound has been reported three times and also adopts a distorted half-boat conformation (Vangehr et al., 1979; Krajewski et al., 1979; Voelter et al., 1981).
In the crystal , the molecules are linked via two independent C—H···O interactions, Table 1, involving the same carbonyl-O6 atom as acceptor. The resulting supramolecular architecture is a chain parallel to the a axis, Fig. 2. These chains pack with no specific intermolecular interactions between them, Fig. 3.
The 3,4-dihydro-2H-pyran ring in the title compound, Fig. 1, is in a distorted half-boat conformation as reflected in the conformational parameters: the puckering amplitude (Q) = 0.497 (5) Å, θ = 52.6 (6)° and φ = 268.6 (7)°. In this conformation, the C4 atom lies 0.633 (6) Å above the plane of the remaining ring atoms which have a r.m.s. of 0.0907 Å. The substituents at the C3 and C4 sites occupy equatorial positions while that at atom C5 is bisectional. The of the unsubstituted parent compound has been reported three times and also adopts a distorted half-boat conformation (Vangehr et al., 1979; Krajewski et al., 1979; Voelter et al., 1981).
In the crystal , the molecules are linked via two independent C—H···O interactions, Table 1, involving the same carbonyl-O6 atom as acceptor. The resulting supramolecular architecture is a chain parallel to the a axis, Fig. 2. These chains pack with no specific intermolecular interactions between them, Fig. 3.
For the structure of the unsubstituted parent compound, determined three times, and having a distorted half-boat conformation, see: Vangehr et al. (1979); Krajewski et al. (1979); Voelter et al. (1981).
To a solution of 3,4,6-tri-oxoacetyl-D-Glucal (3 mmol) in acetonitrile (9 mL) at 373 K under a N2 atmosphere was added N-iodosuccinimide (3.6 mmol) and silver nitrate (0.6 mmol) as catalyst followed by stirring for 4 h. After consumption of the starting material (TLC monitoring), the reaction mixture was filtered through a sintered funnel (using Celite) and the filtrate was then evaporated giving a crude product which was purified by silica gel
(20-30% of EtOAc/hexane) to obtain the title compound. Suitable crystals were obtained by keeping the EtOAc solution of the product at 277 K for 48 h.1H NMR (CDCl3, 300 MHz): δ 6.73 (s, 1H), 5.44 (d, J = 5.1 Hz, 1H), 5.18 (dd, J = 5.1, 7.0 Hz, 1>H), 4.37-4.30 (m, 2H), 4.08-4.18 (m, 1H), 2.09 (s, 3H), 2.05 (s, 3H), 2.04 (s, 3H). 13C NMR (CDCl3, 75 MHz) δ = 170.5, 170.3, 169.4, 149.4, 74.0, 70.6, 67.6, 66.3, 61.0, 20.9, 20.8, 20.7 ppm. HRMS: calcd. for C12H15IO7 [M + H]+ 397.9862; found: 397.9863.
detailsCarbon-bound H-atoms were placed in calculated positions (C—H = 0.93 to 0.98 Å) and were included in the
in the riding model approximation, with Uiso(H) = 1.2–1.5Ueq(C).Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SIR (Burla et al., 2014; program(s) used to refine structure: SHELXL2014 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: MarvinSketch (ChemAxon, 2010) and publCIF (Westrip, 2010).C12H15IO7 | Dx = 1.683 Mg m−3 |
Mr = 398.14 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, P212121 | Cell parameters from 3256 reflections |
a = 7.9048 (2) Å | θ = 2.7–25.1° |
b = 8.7521 (2) Å | µ = 2.06 mm−1 |
c = 22.7094 (5) Å | T = 293 K |
V = 1571.12 (6) Å3 | Irregular, colourless |
Z = 4 | 0.35 × 0.24 × 0.11 mm |
F(000) = 784 |
Bruker APEXII CCD diffractometer | 2456 reflections with I > 2σ(I) |
φ and ω scans | Rint = 0.019 |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | θmax = 25.4°, θmin = 1.8° |
Tmin = 0.601, Tmax = 0.745 | h = −9→5 |
6116 measured reflections | k = −7→10 |
2818 independent reflections | l = −27→27 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.028 | H-atom parameters constrained |
wR(F2) = 0.071 | w = 1/[σ2(Fo2) + (0.0299P)2 + 0.3563P] where P = (Fo2 + 2Fc2)/3 |
S = 1.04 | (Δ/σ)max < 0.001 |
2818 reflections | Δρmax = 0.28 e Å−3 |
184 parameters | Δρmin = −0.58 e Å−3 |
0 restraints | Absolute structure: Flack x determined using 925 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013) |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.000 (11) |
C12H15IO7 | V = 1571.12 (6) Å3 |
Mr = 398.14 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 7.9048 (2) Å | µ = 2.06 mm−1 |
b = 8.7521 (2) Å | T = 293 K |
c = 22.7094 (5) Å | 0.35 × 0.24 × 0.11 mm |
Bruker APEXII CCD diffractometer | 2818 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2456 reflections with I > 2σ(I) |
Tmin = 0.601, Tmax = 0.745 | Rint = 0.019 |
6116 measured reflections |
R[F2 > 2σ(F2)] = 0.028 | H-atom parameters constrained |
wR(F2) = 0.071 | Δρmax = 0.28 e Å−3 |
S = 1.04 | Δρmin = −0.58 e Å−3 |
2818 reflections | Absolute structure: Flack x determined using 925 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013) |
184 parameters | Absolute structure parameter: 0.000 (11) |
0 restraints |
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. |
x | y | z | Uiso*/Ueq | ||
I | 0.55529 (6) | 0.37319 (5) | 0.49032 (2) | 0.1044 (2) | |
O1 | 0.5090 (4) | 0.9803 (5) | 0.31664 (17) | 0.0798 (10) | |
O2 | 0.7080 (7) | 1.1290 (7) | 0.2782 (3) | 0.141 (2) | |
O3 | 0.8630 (3) | 0.8456 (4) | 0.37365 (13) | 0.0609 (8) | |
O4 | 0.8637 (5) | 0.7615 (5) | 0.28034 (15) | 0.0839 (11) | |
O5 | 0.8078 (4) | 0.5163 (4) | 0.38956 (12) | 0.0603 (8) | |
O6 | 1.0344 (5) | 0.4998 (6) | 0.44747 (19) | 0.1042 (14) | |
O7 | 0.4218 (4) | 0.8098 (5) | 0.41934 (15) | 0.0749 (9) | |
C1 | 0.5672 (6) | 0.5851 (6) | 0.44833 (17) | 0.0637 (11) | |
C2 | 0.4291 (6) | 0.6670 (7) | 0.44323 (19) | 0.0728 (14) | |
H2 | 0.3287 | 0.6246 | 0.4569 | 0.087* | |
C3 | 0.5830 (5) | 0.8834 (6) | 0.41154 (19) | 0.0653 (12) | |
H3 | 0.6264 | 0.9136 | 0.4502 | 0.078* | |
C4 | 0.7049 (5) | 0.7701 (5) | 0.38426 (17) | 0.0514 (10) | |
H4 | 0.6585 | 0.7334 | 0.3468 | 0.062* | |
C5 | 0.7335 (5) | 0.6361 (6) | 0.42476 (16) | 0.0576 (10) | |
H5 | 0.8095 | 0.6647 | 0.4570 | 0.069* | |
C6 | 0.5543 (7) | 1.0241 (6) | 0.3756 (3) | 0.0825 (14) | |
H6A | 0.4643 | 1.0846 | 0.3929 | 0.099* | |
H6B | 0.6564 | 1.0855 | 0.3749 | 0.099* | |
C7 | 0.5931 (7) | 1.0403 (7) | 0.2711 (3) | 0.0887 (18) | |
C8 | 0.5349 (9) | 0.9756 (11) | 0.2140 (3) | 0.121 (3) | |
H8A | 0.5497 | 0.8667 | 0.2143 | 0.181* | |
H8B | 0.6000 | 1.0190 | 0.1824 | 0.181* | |
H8C | 0.4174 | 0.9993 | 0.2083 | 0.181* | |
C9 | 0.9308 (6) | 0.8302 (5) | 0.3190 (2) | 0.0607 (11) | |
C10 | 1.0949 (6) | 0.9124 (7) | 0.3156 (3) | 0.0869 (16) | |
H10A | 1.0799 | 1.0066 | 0.2946 | 0.130* | |
H10B | 1.1762 | 0.8500 | 0.2954 | 0.130* | |
H10C | 1.1348 | 0.9338 | 0.3547 | 0.130* | |
C11 | 0.9611 (6) | 0.4617 (6) | 0.4043 (2) | 0.0653 (11) | |
C12 | 1.0198 (7) | 0.3483 (8) | 0.3605 (3) | 0.0952 (19) | |
H12A | 1.1130 | 0.2915 | 0.3766 | 0.143* | |
H12B | 1.0556 | 0.4002 | 0.3254 | 0.143* | |
H12C | 0.9290 | 0.2796 | 0.3512 | 0.143* |
U11 | U22 | U33 | U12 | U13 | U23 | |
I | 0.1334 (4) | 0.0973 (3) | 0.0825 (3) | −0.0195 (3) | 0.0270 (2) | 0.0107 (2) |
O1 | 0.0605 (18) | 0.092 (3) | 0.087 (2) | −0.0091 (16) | −0.0051 (16) | 0.015 (2) |
O2 | 0.126 (4) | 0.127 (4) | 0.169 (5) | −0.048 (4) | 0.012 (3) | 0.045 (4) |
O3 | 0.0480 (14) | 0.074 (2) | 0.0606 (16) | −0.0122 (14) | 0.0004 (12) | −0.0116 (16) |
O4 | 0.080 (2) | 0.114 (3) | 0.058 (2) | −0.022 (2) | 0.0163 (18) | −0.013 (2) |
O5 | 0.0586 (16) | 0.076 (2) | 0.0461 (15) | 0.0052 (15) | −0.0067 (13) | −0.0102 (15) |
O6 | 0.075 (2) | 0.146 (4) | 0.092 (3) | 0.021 (3) | −0.030 (2) | −0.026 (3) |
O7 | 0.0491 (16) | 0.105 (3) | 0.0702 (19) | 0.0004 (17) | 0.0113 (15) | −0.0053 (19) |
C1 | 0.069 (3) | 0.081 (3) | 0.0416 (19) | −0.010 (3) | 0.0058 (19) | −0.006 (2) |
C2 | 0.066 (3) | 0.102 (4) | 0.050 (2) | −0.018 (3) | 0.017 (2) | −0.014 (3) |
C3 | 0.056 (2) | 0.085 (3) | 0.055 (2) | −0.006 (3) | 0.0020 (18) | −0.020 (3) |
C4 | 0.0427 (19) | 0.069 (3) | 0.042 (2) | −0.0070 (19) | −0.0024 (17) | −0.011 (2) |
C5 | 0.059 (2) | 0.077 (3) | 0.0368 (18) | −0.011 (2) | −0.0018 (16) | −0.011 (2) |
C6 | 0.068 (3) | 0.073 (3) | 0.107 (4) | 0.001 (3) | 0.008 (3) | −0.011 (3) |
C7 | 0.063 (3) | 0.086 (4) | 0.118 (5) | 0.007 (3) | 0.004 (3) | 0.041 (4) |
C8 | 0.102 (4) | 0.174 (8) | 0.086 (4) | 0.001 (5) | −0.008 (4) | 0.057 (5) |
C9 | 0.052 (2) | 0.065 (3) | 0.065 (3) | 0.002 (2) | 0.010 (2) | 0.002 (2) |
C10 | 0.059 (3) | 0.092 (4) | 0.109 (4) | −0.010 (3) | 0.017 (3) | 0.007 (3) |
C11 | 0.058 (2) | 0.084 (3) | 0.055 (2) | 0.001 (3) | 0.003 (2) | 0.005 (2) |
C12 | 0.086 (4) | 0.116 (5) | 0.084 (4) | 0.023 (4) | 0.010 (3) | −0.013 (4) |
I—C1 | 2.087 (5) | C4—C5 | 1.507 (6) |
O1—C7 | 1.336 (7) | C4—H4 | 0.9800 |
O1—C6 | 1.438 (7) | C5—H5 | 0.9800 |
O2—C7 | 1.205 (8) | C6—H6A | 0.9700 |
O3—C9 | 1.359 (5) | C6—H6B | 0.9700 |
O3—C4 | 1.434 (5) | C7—C8 | 1.490 (10) |
O4—C9 | 1.188 (6) | C8—H8A | 0.9600 |
O5—C11 | 1.345 (6) | C8—H8B | 0.9600 |
O5—C5 | 1.444 (5) | C8—H8C | 0.9600 |
O6—C11 | 1.186 (6) | C9—C10 | 1.486 (7) |
O7—C2 | 1.364 (7) | C10—H10A | 0.9600 |
O7—C3 | 1.439 (5) | C10—H10B | 0.9600 |
C1—C2 | 1.311 (7) | C10—H10C | 0.9600 |
C1—C5 | 1.488 (6) | C11—C12 | 1.479 (7) |
C2—H2 | 0.9300 | C12—H12A | 0.9600 |
C3—C6 | 1.495 (8) | C12—H12B | 0.9600 |
C3—C4 | 1.515 (6) | C12—H12C | 0.9600 |
C3—H3 | 0.9800 | ||
C7—O1—C6 | 119.4 (5) | O1—C6—H6B | 109.9 |
C9—O3—C4 | 116.8 (3) | C3—C6—H6B | 109.9 |
C11—O5—C5 | 119.1 (3) | H6A—C6—H6B | 108.3 |
C2—O7—C3 | 114.9 (4) | O2—C7—O1 | 121.7 (7) |
C2—C1—C5 | 122.6 (5) | O2—C7—C8 | 126.4 (6) |
C2—C1—I | 119.3 (4) | O1—C7—C8 | 111.8 (5) |
C5—C1—I | 118.1 (4) | C7—C8—H8A | 109.5 |
C1—C2—O7 | 124.9 (4) | C7—C8—H8B | 109.5 |
C1—C2—H2 | 117.6 | H8A—C8—H8B | 109.5 |
O7—C2—H2 | 117.6 | C7—C8—H8C | 109.5 |
O7—C3—C6 | 107.6 (4) | H8A—C8—H8C | 109.5 |
O7—C3—C4 | 108.7 (4) | H8B—C8—H8C | 109.5 |
C6—C3—C4 | 114.3 (4) | O4—C9—O3 | 123.3 (4) |
O7—C3—H3 | 108.7 | O4—C9—C10 | 126.6 (4) |
C6—C3—H3 | 108.7 | O3—C9—C10 | 110.1 (4) |
C4—C3—H3 | 108.7 | C9—C10—H10A | 109.5 |
O3—C4—C5 | 109.3 (3) | C9—C10—H10B | 109.5 |
O3—C4—C3 | 108.7 (3) | H10A—C10—H10B | 109.5 |
C5—C4—C3 | 110.8 (4) | C9—C10—H10C | 109.5 |
O3—C4—H4 | 109.3 | H10A—C10—H10C | 109.5 |
C5—C4—H4 | 109.3 | H10B—C10—H10C | 109.5 |
C3—C4—H4 | 109.3 | O6—C11—O5 | 123.1 (5) |
O5—C5—C1 | 109.9 (4) | O6—C11—C12 | 126.2 (5) |
O5—C5—C4 | 106.8 (3) | O5—C11—C12 | 110.7 (4) |
C1—C5—C4 | 108.7 (4) | C11—C12—H12A | 109.5 |
O5—C5—H5 | 110.5 | C11—C12—H12B | 109.5 |
C1—C5—H5 | 110.5 | H12A—C12—H12B | 109.5 |
C4—C5—H5 | 110.5 | C11—C12—H12C | 109.5 |
O1—C6—C3 | 109.1 (4) | H12A—C12—H12C | 109.5 |
O1—C6—H6A | 109.9 | H12B—C12—H12C | 109.5 |
C3—C6—H6A | 109.9 | ||
C5—C1—C2—O7 | −3.9 (7) | C2—C1—C5—C4 | −13.0 (6) |
I—C1—C2—O7 | 176.7 (3) | I—C1—C5—C4 | 166.4 (3) |
C3—O7—C2—C1 | −13.7 (6) | O3—C4—C5—O5 | −76.7 (4) |
C2—O7—C3—C6 | 170.0 (4) | C3—C4—C5—O5 | 163.5 (3) |
C2—O7—C3—C4 | 45.7 (5) | O3—C4—C5—C1 | 164.8 (3) |
C9—O3—C4—C5 | 108.8 (4) | C3—C4—C5—C1 | 45.0 (4) |
C9—O3—C4—C3 | −130.1 (4) | C7—O1—C6—C3 | −128.3 (5) |
O7—C3—C4—O3 | 177.0 (3) | O7—C3—C6—O1 | −68.9 (5) |
C6—C3—C4—O3 | 56.8 (5) | C4—C3—C6—O1 | 51.9 (5) |
O7—C3—C4—C5 | −62.8 (4) | C6—O1—C7—O2 | 1.0 (8) |
C6—C3—C4—C5 | 177.0 (4) | C6—O1—C7—C8 | 177.0 (5) |
C11—O5—C5—C1 | −121.9 (4) | C4—O3—C9—O4 | 1.9 (6) |
C11—O5—C5—C4 | 120.4 (4) | C4—O3—C9—C10 | −179.0 (4) |
C2—C1—C5—O5 | −129.5 (5) | C5—O5—C11—O6 | 5.3 (7) |
I—C1—C5—O5 | 49.9 (4) | C5—O5—C11—C12 | −175.9 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
C2—H2···O6i | 0.93 | 2.58 | 3.448 (7) | 156 |
C3—H3···O6ii | 0.98 | 2.55 | 3.383 (6) | 143 |
Symmetry codes: (i) x−1, y, z; (ii) x−1/2, −y+3/2, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
C2—H2···O6i | 0.93 | 2.58 | 3.448 (7) | 156 |
C3—H3···O6ii | 0.98 | 2.55 | 3.383 (6) | 143 |
Symmetry codes: (i) x−1, y, z; (ii) x−1/2, −y+3/2, −z+1. |
Acknowledgements
We thank Professor Regina H. A. Santos from IQSC–USP for the X-ray data collection. The Brazilian agencies CNPq (305626/2013–2 to JZS; 306121/2013-2 to IC; 308320/2010-7 to HAS) and FAPESP are acknowledged for financial support.
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