Methyl 6-de­oxy-6-iodo-2,3-O-iso­propyl­idene-α-d-manno­pyran­oside

Gültekin, Z.; Frey, W.; Çaylak Delibaş, N.; Hökelek, T.

doi:10.1107/S1600536813022629

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 69| Part 9| September 2013| Pages o1449-o1450

doi:10.1107/S1600536813022629

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Methyl 6-deoxy-6-iodo-2,3-O-isopropylidene-α-D-mannopyranoside

Zeynep Gültekin,^a Wolfgang Frey,^b Nagihan Çaylak Delibaş ^c and Tuncer Hökelek ^d ^*

^aDepartment of Chemistry, Çankırı Karatekin University, TR-18100, Çankırı, Turkey, ^bUniversität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany, ^cDepartment of Physics, Sakarya University, 54187 Esentepe, Sakarya, Turkey, and ^dDepartment of Physics, Hacettepe University, 06800 Beytepe, Ankara, Turkey
^*Correspondence e-mail: merzifon@hacettepe.edu.tr

(Received 1 August 2013; accepted 12 August 2013; online 17 August 2013)

In the title compound, C₁₀H₁₇IO₅, the six-membered tetrahydropyran ring and the five-membered 1,3-dioxolane ring adopt sofa and envelope conformations, respectively. In the crystal, O—H⋯O and C—H⋯O hydrogen bonds link the molecules into layers nearly parallel to the bc plane.

Related literature

For carbohydrates which are important for the preparation of unsaturated aldehydes, see: Kleban et al. (2000 ); Dransfield et al. (1999 ); Greul et al. (2001 ). For conversions of unsaturated aldehydes to oximes, nitrones and nitrile oxides, see: Dransfield et al. (1999); Bernet & Vasella (1979 ); Greul et al. (2001); Gallos et al. (1999 ); Kleban et al. (2001 ). For the methods reported in the literature for the preparation of the title compound, see: Garegg & Samuelsson (1980 ); Bundle et al. (1988 ); Ichikawa et al. (2004 ). For the synthesis of methyl 2,3-O-isopropylidene-α-D-mannopyranoside, see: Evans & Parrish (1977 ); Isobe et al. (1981 ). For ring-puckering parameters, see: Cremer & Pople (1975 ).

Experimental

Crystal data

C₁₀H₁₇IO₅
M_r = 344.14
Monoclinic, P 2₁
a = 8.3121 (8) Å
b = 10.3911 (10) Å
c = 8.3128 (8) Å
β = 118.639 (3)°
V = 630.15 (11) Å³
Z = 2
Mo Kα radiation
μ = 2.55 mm⁻¹
T = 100 K
0.99 × 0.58 × 0.44 mm

Data collection

Bruker Kappa APEXII DUO diffractometer
Absorption correction: numerical (Blessing, 1995 ) T_min = 0.187, T_max = 0.401
13656 measured reflections
3827 independent reflections
3803 reflections with I > 2σ(I)
R_int = 0.027
Standard reflections: 0

Refinement

R[F² > 2σ(F²)] = 0.016
wR(F²) = 0.043
S = 1.24
3827 reflections
153 parameters
3 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.86 e Å⁻³
Δρ_min = −0.82 e Å⁻³
Absolute structure: Flack (1983 ), 1811 Friedel pairs
Absolute structure parameter: 0.003 (12)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2A⋯O3ⁱ	0.82 (3)	2.03 (3)	2.807 (2)	157 (3)
C10—H10C⋯O2ⁱⁱ	0.98	2.51	3.390 (3)	149
Symmetry codes: (i) $[-x+2, y-{\script{1\over 2}}, -z+2]$ ; (ii) x, y, z+1.

Data collection: APEX2 (Bruker, 2008 ); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536813022629/xu5727sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813022629/xu5727Isup2.hkl

checkCIF report

Comment top

Various carbohydrates have been considerably important for the preparation of unsaturated aldehydes (Kleban et al., 2000; Dransfield et al., 1999; Greul et al., 2001). Conversions of unsaturated aldehydes to oximes (Dransfield et al., 1999), nitrones (Bernet & Vasella, 1979; Greul et al., 2001), nitrile oxides (Gallos et al., 1999; Kleban et al., 2001) and their intramolecular cycloadditions have been reported. These cycloadducts are useful intermediates for the syntheses of polyhydroxylated aminocyclopentane derivatives (Greul et al., 2001; Kleban et al., 2001).

In the title compound (Fig. 1), the ring A (C1–C5/O1) is not planar, but adopts a sofa conformation with puckering parameters (Cremer & Pople, 1975) Q_T = 0.551 (2) Å, ϕ = -113.1 (5)° and θ = 158.5 (2)°. The conformation of ring B (O4/O5/C3/C4/C8) is an envelope, with atom C4 at the flap position, -0.573 (2) Å from the mean plane through the other four atoms. Rings A and B have local pseudo-mirror planes running through C1 and C4 (for ring A), and running through C4 and the midpoint of the O4—C8 bond (for ring B).

In the crystal structure, intermolecular O—H···O and C—H···O hydrogen bonds (Table 1) link the molecules into layers nearly parallel to the bc plane (Fig. 2).

Related literature top

For carbohydrates which are important for the preparation of unsaturated aldehydes, see: Kleban et al. (2000); Dransfield et al. (1999); Greul et al. (2001). For conversions of unsaturated aldehydes to oximes, nitrones and nitrile oxides, see: Dransfield et al. (1999); Bernet & Vasella (1979); Greul et al. (2001); Gallos et al. (1999); Kleban et al. (2001). For the methods reported in the literature for the preparation of the title compound, see: Garegg & Samuelsson (1980); Bundle et al. (1988); Ichikawa et al. (2004). For the synthesis of methyl 2,3-O-isopropylidene-α-D-mannopyranoside, see: Evans & Parrish (1977); Isobe et al. (1981). For ring-puckering parameters, see: Cremer & Pople (1975).

Experimental top

The title compound was synthesized in two steps starting from α-D-mannopyranoside by the literature methods (Garegg & Samuelsson, 1980; Bundle et al., 1988; Ichikawa et al., 2004). To a solution of methyl 2,3-O-isopropylidene-α-D-mannopyranoside (Evans & Parrish, 1977; Isobe et al., 1981) (2.50 g, 10.66 mmol) in dry toluene (70 ml, dissolved at 353 K) were added PPh₃ (4.30 g, 15.90 mmol), imidazole (2.17 g, 31.98 mmol) and iodine (3.80 g, 14.90 mmol) sequentially. The reaction mixture was refluxed for 3 h. 20 ml water was added, and then the mixture was extracted with EtOAc (4 × 20 ml). The combined organic phase was washed with brine (300 ml) and then dried over MgSO₄. The filtrate was concentrated under reduced pressure, and the residue was purified by chromatography (PE:EE 70:30) to afford the iodo compound as a colourless crystalline solid (yield: 90%), m.p. 383–384 K.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of the title compound, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. A partial packing diagram. Hydrogen bonds are shown as dashed lines. H atoms not involved in hydrogen bonding have been omitted for clarity.

Methyl 6-deoxy-6-iodo-2,3-O-isopropylidene-α-D-mannopyranoside top

Crystal data top

C₁₀H₁₇IO₅	F(000) = 340
M_r = 344.14	D_x = 1.814 Mg m⁻³
Monoclinic, P2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 3798 reflections
a = 8.3121 (8) Å	θ = 2.8–30.5°
b = 10.3911 (10) Å	µ = 2.55 mm⁻¹
c = 8.3128 (8) Å	T = 100 K
β = 118.639 (3)°	Prism, colourless
V = 630.15 (11) Å³	0.99 × 0.58 × 0.44 mm
Z = 2

Data collection top

Bruker Kappa APEXII DUO diffractometer	3827 independent reflections
Radiation source: fine-focus sealed tube	3803 reflections with I > 2σ(I)
Triumph monochromator	R_int = 0.027
ϕ and ω scans	θ_max = 30.5°, θ_min = 2.8°
Absorption correction: numerical (Blessing, 1995)	h = −11→11
T_min = 0.187, T_max = 0.401	k = −14→14
13656 measured reflections	l = −11→11

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F² > 2σ(F²)] = 0.016	w = 1/[σ²(F_o²) + (0.0159P)² + 0.0596P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.043	(Δ/σ)_max = 0.001
S = 1.24	Δρ_max = 0.86 e Å⁻³
3827 reflections	Δρ_min = −0.82 e Å⁻³
153 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
3 restraints	Extinction coefficient: 0.0949 (17)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 1811 Friedel pairs
Secondary atom site location: difference Fourier map	Absolute structure parameter: 0.003 (12)

Crystal data top

C₁₀H₁₇IO₅	V = 630.15 (11) Å³
M_r = 344.14	Z = 2
Monoclinic, P2₁	Mo Kα radiation
a = 8.3121 (8) Å	µ = 2.55 mm⁻¹
b = 10.3911 (10) Å	T = 100 K
c = 8.3128 (8) Å	0.99 × 0.58 × 0.44 mm
β = 118.639 (3)°

Data collection top

Bruker Kappa APEXII DUO diffractometer	3827 independent reflections
Absorption correction: numerical (Blessing, 1995)	3803 reflections with I > 2σ(I)
T_min = 0.187, T_max = 0.401	R_int = 0.027
13656 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.016	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.043	Δρ_max = 0.86 e Å⁻³
S = 1.24	Δρ_min = −0.82 e Å⁻³
3827 reflections	Absolute structure: Flack (1983), 1811 Friedel pairs
153 parameters	Absolute structure parameter: 0.003 (12)
3 restraints

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
I1	0.388710 (12)	0.741920 (17)	0.435425 (11)	0.01675 (5)
O1	0.59121 (17)	0.64971 (12)	0.87699 (17)	0.0126 (2)
O2	0.91193 (19)	0.47140 (13)	0.78471 (18)	0.0150 (2)
H2A	0.998 (4)	0.426 (3)	0.855 (4)	0.045 (10)*
O3	0.76827 (18)	0.82125 (12)	1.0565 (2)	0.0143 (2)
O4	1.04540 (17)	0.44287 (13)	1.19016 (17)	0.0130 (2)
O5	0.80476 (18)	0.50343 (12)	1.23592 (19)	0.0143 (2)
C1	0.6958 (2)	0.62356 (15)	0.7844 (2)	0.0113 (3)
H1	0.7689	0.7009	0.7875	0.014*
C2	0.8224 (2)	0.51098 (16)	0.8849 (2)	0.0111 (3)
H2	0.7473	0.4379	0.8912	0.013*
C3	0.9584 (2)	0.55251 (16)	1.0784 (2)	0.0105 (3)
H3	1.0518	0.6125	1.0768	0.013*
C4	0.8628 (2)	0.61411 (15)	1.1762 (2)	0.0119 (3)
H4	0.9530	0.6646	1.2845	0.014*
C5	0.6980 (3)	0.69768 (17)	1.0559 (2)	0.0118 (3)
H5	0.6183	0.7038	1.1152	0.014*
C6	0.6277 (3)	0.91625 (18)	0.9709 (3)	0.0226 (4)
H6A	0.5518	0.8950	0.8409	0.034*
H6B	0.6839	1.0010	0.9823	0.034*
H6C	0.5510	0.9178	1.0309	0.034*
C7	0.5644 (3)	0.58663 (17)	0.5897 (3)	0.0158 (3)
H7A	0.4882	0.5136	0.5903	0.019*
H7B	0.6351	0.5574	0.5287	0.019*
C8	0.9482 (3)	0.40997 (16)	1.2897 (2)	0.0143 (3)
C9	0.8614 (3)	0.27863 (19)	1.2334 (3)	0.0220 (4)
H9A	0.7752	0.2655	1.2809	0.033*
H9B	0.9570	0.2124	1.2832	0.033*
H9C	0.7957	0.2727	1.0993	0.033*
C10	1.0810 (3)	0.4196 (2)	1.4915 (3)	0.0231 (4)
H10A	1.1313	0.5070	1.5203	0.035*
H10B	1.1809	0.3579	1.5237	0.035*
H10C	1.0172	0.4004	1.5618	0.035*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
I1	0.01472 (6)	0.01220 (5)	0.01494 (6)	0.00098 (5)	0.00036 (4)	0.00353 (5)
O1	0.0087 (5)	0.0137 (5)	0.0134 (6)	0.0003 (4)	0.0036 (5)	−0.0021 (4)
O2	0.0145 (6)	0.0201 (6)	0.0104 (6)	0.0058 (5)	0.0060 (5)	0.0004 (5)
O3	0.0097 (6)	0.0093 (5)	0.0215 (7)	−0.0009 (4)	0.0055 (5)	−0.0018 (4)
O4	0.0107 (6)	0.0189 (6)	0.0111 (6)	0.0046 (5)	0.0065 (5)	0.0047 (5)
C1	0.0102 (7)	0.0112 (6)	0.0108 (7)	0.0007 (5)	0.0037 (6)	−0.0009 (5)
C2	0.0096 (7)	0.0130 (6)	0.0099 (7)	0.0014 (6)	0.0042 (6)	0.0002 (5)
C3	0.0078 (7)	0.0132 (6)	0.0101 (7)	0.0008 (5)	0.0039 (6)	0.0009 (5)
C4	0.0113 (7)	0.0131 (7)	0.0118 (7)	0.0001 (6)	0.0061 (6)	−0.0006 (6)
C5	0.0102 (7)	0.0116 (6)	0.0125 (8)	−0.0010 (5)	0.0046 (7)	−0.0018 (5)
O5	0.0138 (6)	0.0148 (5)	0.0175 (6)	0.0041 (4)	0.0102 (5)	0.0048 (5)
C6	0.0155 (9)	0.0131 (8)	0.0329 (11)	0.0036 (6)	0.0065 (8)	0.0002 (7)
C7	0.0150 (8)	0.0134 (7)	0.0118 (8)	0.0023 (6)	0.0005 (7)	0.0008 (6)
C8	0.0146 (8)	0.0173 (7)	0.0147 (8)	0.0044 (6)	0.0100 (7)	0.0039 (6)
C9	0.0234 (10)	0.0161 (7)	0.0313 (11)	0.0018 (6)	0.0171 (9)	0.0045 (6)
C10	0.0239 (10)	0.0326 (10)	0.0132 (9)	0.0095 (8)	0.0093 (8)	0.0069 (7)

Geometric parameters (Å, º) top

I1—C7	2.1414 (18)	C4—O5	1.425 (2)
O1—C1	1.4362 (19)	C4—C5	1.522 (3)
O1—C5	1.408 (2)	C4—H4	1.0000
O2—C2	1.4182 (18)	C5—H5	1.0000
O2—H2A	0.823 (16)	C6—H6A	0.9800
O3—C5	1.409 (2)	C6—H6B	0.9800
O3—C6	1.432 (2)	C6—H6C	0.9800
O4—C8	1.4480 (19)	C7—H7A	0.9900
O5—C8	1.433 (2)	C7—H7B	0.9900
C1—C2	1.527 (2)	C8—C9	1.509 (3)
C1—C7	1.505 (2)	C8—C10	1.506 (3)
C1—H1	1.0000	C9—H9A	0.9800
C2—C3	1.519 (2)	C9—H9B	0.9800
C2—H2	1.0000	C9—H9C	0.9800
C3—O4	1.428 (2)	C10—H10A	0.9800
C3—C4	1.524 (2)	C10—H10B	0.9800
C3—H3	1.0000	C10—H10C	0.9800

C5—O1—C1	113.31 (13)	O3—C5—H5	108.2
C2—O2—H2A	106 (3)	C4—C5—H5	108.2
C5—O3—C6	112.85 (13)	O3—C6—H6A	109.5
C3—O4—C8	108.25 (12)	O3—C6—H6B	109.5
C4—O5—C8	106.61 (12)	O3—C6—H6C	109.5
O1—C1—C2	106.69 (13)	H6A—C6—H6B	109.5
O1—C1—C7	108.12 (14)	H6A—C6—H6C	109.5
O1—C1—H1	110.5	H6B—C6—H6C	109.5
C2—C1—H1	110.5	I1—C7—H7A	109.0
C7—C1—C2	110.34 (13)	I1—C7—H7B	109.0
C7—C1—H1	110.5	C1—C7—I1	112.76 (11)
O2—C2—C1	108.61 (13)	C1—C7—H7A	109.0
O2—C2—C3	111.71 (13)	C1—C7—H7B	109.0
O2—C2—H2	109.1	H7A—C7—H7B	107.8
C1—C2—H2	109.1	O4—C8—C9	110.52 (14)
C3—C2—C1	109.25 (13)	O4—C8—C10	107.99 (15)
C3—C2—H2	109.1	O5—C8—O4	105.68 (13)
O4—C3—C2	110.49 (14)	O5—C8—C9	108.28 (16)
O4—C3—C4	102.62 (12)	O5—C8—C10	111.02 (14)
O4—C3—H3	110.6	C10—C8—C9	113.10 (16)
C2—C3—C4	111.72 (14)	C8—C9—H9A	109.5
C2—C3—H3	110.6	C8—C9—H9B	109.5
C4—C3—H3	110.6	C8—C9—H9C	109.5
O5—C4—C3	101.37 (12)	H9A—C9—H9B	109.5
O5—C4—C5	109.94 (14)	H9A—C9—H9C	109.5
O5—C4—H4	110.0	H9B—C9—H9C	109.5
C3—C4—H4	110.0	C8—C10—H10A	109.5
C5—C4—C3	115.09 (14)	C8—C10—H10B	109.5
C5—C4—H4	110.0	C8—C10—H10C	109.5
O1—C5—O3	112.13 (14)	H10A—C10—H10B	109.5
O1—C5—C4	113.92 (14)	H10A—C10—H10C	109.5
O1—C5—H5	108.2	H10B—C10—H10C	109.5
O3—C5—C4	106.06 (14)

C5—O1—C1—C2	67.22 (16)	C2—C1—C7—I1	−177.65 (10)
C5—O1—C1—C7	−174.10 (14)	O2—C2—C3—O4	−75.14 (16)
C1—O1—C5—O3	67.12 (17)	O2—C2—C3—C4	171.29 (13)
C1—O1—C5—C4	−53.35 (18)	C1—C2—C3—O4	164.67 (12)
C6—O3—C5—O1	63.69 (19)	C1—C2—C3—C4	51.10 (17)
C6—O3—C5—C4	−171.39 (15)	C2—C3—O4—C8	−95.94 (15)
C3—O4—C8—O5	−0.79 (18)	C4—C3—O4—C8	23.30 (17)
C3—O4—C8—C9	116.14 (17)	O4—C3—C4—O5	−37.10 (16)
C3—O4—C8—C10	−119.67 (15)	O4—C3—C4—C5	−155.67 (14)
C4—O5—C8—O4	−24.18 (18)	C2—C3—C4—O5	81.28 (16)
C4—O5—C8—C9	−142.61 (15)	C2—C3—C4—C5	−37.29 (19)
C4—O5—C8—C10	92.67 (16)	C3—C4—O5—C8	37.73 (17)
O1—C1—C2—O2	172.83 (13)	C5—C4—O5—C8	159.94 (14)
O1—C1—C2—C3	−65.09 (16)	O5—C4—C5—O1	−76.30 (17)
C7—C1—C2—O2	55.61 (18)	O5—C4—C5—O3	159.88 (12)
C7—C1—C2—C3	177.69 (13)	C3—C4—C5—O1	37.36 (19)
O1—C1—C7—I1	66.01 (15)	C3—C4—C5—O3	−86.45 (16)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2A···O3ⁱ	0.82 (3)	2.03 (3)	2.807 (2)	157 (3)
C10—H10C···O2ⁱⁱ	0.98	2.51	3.390 (3)	149

Symmetry codes: (i) −x+2, y−1/2, −z+2; (ii) x, y, z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2A···O3ⁱ	0.82 (3)	2.03 (3)	2.807 (2)	157 (3)
C10—H10C···O2ⁱⁱ	0.98	2.51	3.390 (3)	149

Symmetry codes: (i) −x+2, y−1/2, −z+2; (ii) x, y, z+1.

Acknowledgements

The authors are indebted to the Research Fund of Çankırı Karatekin University (grant No. BAP:2011/06) for financial support, and thank Professor V. Jäger of Stuttgart University, Germany, for helpful discussions.

References

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