Methyl 4-O-benzyl-α-l-rhamno-pyrano-side.

In the title compound, C14H20O5, an inter-mediate in the synthesis of oligosaccharides, the glycosidic [H-C-O-C(H3)] torsion angle ϕH is 52.3° and the exo-cyclic [H-C-O-C(H2)] torsion angle θH is -11.7°. The hexa-pyran-ose ring has a chair conformation. In the crystal, mol-ecules are linked by O-H⋯O hydrogen bonds, forming chains propagating along [010]. Enclosed within the chains are R 3 (3)(12) ring motifs involving three mol-ecules. The chains are linked via C-H⋯π inter-actions, forming a three-dimensional network.

Related literature

For a description of l-rhamnose as part of polysaccharides, see: Ansaruzzaman et al. (1996 ▶); Marie et al. (1998 ▶); Säwén et al. (2012 ▶). For a description of syntheses in which the title compound has been used, see: Eklund et al. (2005 ▶); Handa et al. (1979 ▶). For the structure of rhamnosyl-containing tris­accharides, see: Eriksson & Widmalm (2012 ▶); Eriksson et al. (1999 ▶); Jonsson et al. (2006 ▶). For further related literature on l-rhamnose, see: Anderson & Ijeh (1994 ▶); Varki et al. (1999 ▶); Haines (1969 ▶); Herget et al. (2008 ▶); Olsson et al. (2005 ▶). For puckering analysis, see: Cremer & Pople (1975 ▶).

Experimental

Crystal data

C14H20O5

M = 268.30

Orthorhombic,

a = 6.5377 (1) Å

b = 9.1848 (2) Å

c = 23.2699 (5) Å

V = 1397.30 (5) Å3

Z = 4

Mo Kα radiation

μ = 0.10 mm−1

T = 293 K

0.25 × 0.12 × 0.05 mm

Data collection

Oxford Diffraction Xcalibur 3 with sapphire 3 CCD diffractometer

Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2004 ▶) T min = 0.921, T max = 1.000

9540 measured reflections

1665 independent reflections

1407 reflections with I > 2σ(I)

R int = 0.040

Refinement

R[F 2 > 2σ(F 2)] = 0.035

wR(F 2) = 0.081

S = 1.00

1665 reflections

177 parameters

H-atom parameters constrained

Δρmax = 0.14 e Å−3

Δρmin = −0.13 e Å−3

Data collection: CrysAlis CCD (Oxford Diffraction, 2004 ▶); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 2004 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: DIAMOND (Brandenburg, 2001 ▶); software used to prepare material for publication: enCIFer (Allen et al., 2004 ▶).

Crystal structure: contains datablock(s) I, rp1. DOI: 10.1107/S1600536814007922/su2708sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536814007922/su2708Isup2.hkl

CCDC reference: 996312

Additional supporting information: crystallographic information; 3D view; checkCIF report

C14H20O5	F(000) = 576
Mr = 268.30	Dx = 1.275 Mg m−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 4263 reflections
a = 6.5377 (1) Å	θ = 3.8–32.2°
b = 9.1848 (2) Å	µ = 0.10 mm−1
c = 23.2699 (5) Å	T = 293 K
V = 1397.30 (5) Å3	Prism, colourless
Z = 4	0.25 × 0.12 × 0.05 mm

Oxford Diffraction Xcalibur 3 with sapphire 3 CCD diffractometer	1665 independent reflections
Radiation source: Enhance (Mo) X-ray Source	1407 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.040
Detector resolution: 16.5467 pixels mm-1	θmax = 26.4°, θmin = 3.8°
ω scans at different φ	h = −3→8
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2004)	k = −11→11
Tmin = 0.921, Tmax = 1.000	l = −28→29
9540 measured reflections

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)] = 0.035	H-atom parameters constrained
wR(F2) = 0.081	w = 1/[σ2(Fo2) + (0.0524P)2] where P = (Fo2 + 2Fc2)/3
S = 1.00	(Δ/σ)max < 0.001
1665 reflections	Δρmax = 0.14 e Å−3
177 parameters	Δρmin = −0.13 e Å−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.013 (2)

Experimental. Spectroscoptic data for the title compound: 1H NMR (CDCl3, ppm, 298K, selected 3JH,H values are given in parenthesis): H1 4.645(1.55); H2 3.903(3.49); H3 3.877(9.12); H4 3.333(9.52); H5 3.700(6.31); H6 1.352; H7 3.345; H40 4.738; H42,H46 7.355; H43,H45 7.360; H44 7.304; HO2 2.574(3.92); HO3 2.470(5.31). 13C NMR (CDCl3, ppm, 298K): C1 100.48; C2 71.20; C3 71.60; C4 81.77; C5 67.14; C6 18.14; C7 54.97; C40 75.11; C41 138.40; C42,C46 128.06; C43,C45 128.75; C44 128.12.NMR experiments were performed on a Bruker Avance III spectrometer operating at a 1H frequency of 700 MHz. The title compound was dissolved in chloroform-d and 1H and 13C resonances were referenced to internal TMS (δ = 0.0) and the solvent resonance (δ = 77.16), respectively. Resonance assignments were performed using standard experiments for oligosaccharides (Widmalm, G. (2007). NMR spectroscopy of carbohydrates and conformational analysis in solution. Comprehensive glycoscience, J. P. Kamerling, Ed., Elsevier, Oxford, Vol. 2, pp. 101–132) and measurement of the heteronuclear coupling constant was carried out by a J-HMBC experiment (Meissner, A. & Sørensen, O. W. (2001). Magn. Reson. Chem.39, 49–52) using two separate experiments with κ values of 59.0 and 99.0, respectively (Jonsson, K. H. M., Pendrill, R. & Widmalm, G. (2011). Magn. Reson. Chem.49, 117–124).

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.

	x	y	z	Uiso*/Ueq
C1	1.0867 (3)	0.5237 (2)	0.04789 (8)	0.0370 (5)
H1	1.1807	0.5419	0.0159	0.044*
C2	0.8931 (3)	0.6130 (2)	0.03845 (8)	0.0317 (5)
H2	0.8232	0.5790	0.0037	0.038*
C3	0.7515 (3)	0.5959 (2)	0.09008 (8)	0.0273 (4)
H3	0.7109	0.4935	0.0933	0.033*
C4	0.8644 (3)	0.6397 (2)	0.14447 (8)	0.0282 (4)
H4	0.8990	0.7435	0.1432	0.034*
C5	1.0597 (3)	0.5481 (2)	0.15042 (8)	0.0314 (4)
H5	1.0212	0.4456	0.1549	0.038*
O5	1.1851 (2)	0.56299 (17)	0.09964 (6)	0.0382 (4)
C6	1.1946 (3)	0.5915 (3)	0.20013 (9)	0.0444 (6)
H6A	1.3178	0.5347	0.1994	0.067*
H6B	1.1234	0.5747	0.2356	0.067*
H6C	1.2284	0.6929	0.1970	0.067*
O1	1.0298 (2)	0.37637 (17)	0.04700 (6)	0.0458 (4)
C7	1.1990 (5)	0.2788 (3)	0.04520 (14)	0.0819 (10)
H7A	1.2799	0.2985	0.0117	0.123*
H7B	1.1498	0.1804	0.0437	0.123*
H7C	1.2813	0.2918	0.0790	0.123*
O2	0.9419 (2)	0.76226 (15)	0.03268 (6)	0.0444 (4)
H2A	0.9920	0.7768	0.0009	0.067*
O3	0.5733 (2)	0.68189 (16)	0.08031 (6)	0.0355 (3)
H3A	0.4761	0.6461	0.0975	0.053*
O4	0.7372 (2)	0.60980 (15)	0.19307 (5)	0.0337 (3)
C40	0.7222 (3)	0.7259 (2)	0.23403 (8)	0.0380 (5)
H40A	0.6411	0.8049	0.2183	0.046*
H40B	0.8573	0.7630	0.2430	0.046*
C41	0.6222 (3)	0.6670 (2)	0.28745 (8)	0.0355 (5)
C42	0.4478 (3)	0.7314 (3)	0.31025 (9)	0.0424 (5)
H42	0.3947	0.8154	0.2937	0.051*
C43	0.3531 (4)	0.6700 (3)	0.35777 (10)	0.0563 (7)
H43	0.2358	0.7130	0.3727	0.068*
C44	0.4302 (5)	0.5471 (3)	0.38299 (10)	0.0601 (7)
H44	0.3630	0.5050	0.4141	0.072*
C45	0.6085 (5)	0.4856 (3)	0.36203 (10)	0.0594 (7)
H45	0.6650	0.4044	0.3799	0.071*
C46	0.7013 (4)	0.5455 (3)	0.31468 (9)	0.0471 (6)
H46	0.8205	0.5033	0.3006	0.057*

	U11	U22	U33	U12	U13	U23
C1	0.0251 (10)	0.0573 (15)	0.0288 (10)	−0.0006 (10)	0.0027 (9)	−0.0024 (9)
C2	0.0274 (9)	0.0430 (12)	0.0247 (9)	−0.0035 (10)	−0.0007 (8)	0.0023 (8)
C3	0.0220 (9)	0.0325 (10)	0.0275 (10)	−0.0004 (8)	−0.0010 (8)	0.0023 (8)
C4	0.0274 (9)	0.0345 (11)	0.0226 (9)	−0.0045 (8)	0.0032 (8)	0.0023 (8)
C5	0.0263 (9)	0.0400 (11)	0.0277 (9)	−0.0027 (9)	−0.0010 (8)	0.0033 (9)
O5	0.0216 (6)	0.0611 (9)	0.0320 (7)	−0.0031 (7)	−0.0010 (6)	0.0002 (7)
C6	0.0342 (11)	0.0628 (15)	0.0362 (11)	−0.0018 (11)	−0.0118 (10)	0.0040 (10)
O1	0.0394 (8)	0.0460 (9)	0.0520 (9)	0.0094 (8)	−0.0054 (8)	−0.0125 (7)
C7	0.0693 (19)	0.0734 (19)	0.103 (2)	0.0371 (18)	−0.0094 (18)	−0.0190 (18)
O2	0.0489 (9)	0.0499 (10)	0.0344 (8)	−0.0046 (8)	0.0109 (7)	0.0105 (7)
O3	0.0228 (7)	0.0481 (8)	0.0357 (8)	0.0034 (7)	0.0002 (6)	0.0070 (7)
O4	0.0351 (7)	0.0410 (8)	0.0250 (7)	−0.0071 (7)	0.0058 (6)	−0.0019 (6)
C40	0.0469 (12)	0.0375 (11)	0.0295 (10)	−0.0021 (11)	0.0033 (10)	−0.0013 (9)
C41	0.0449 (11)	0.0374 (12)	0.0244 (10)	−0.0076 (10)	−0.0002 (9)	−0.0050 (8)
C42	0.0451 (12)	0.0494 (13)	0.0326 (11)	−0.0021 (12)	−0.0008 (10)	−0.0062 (10)
C43	0.0519 (14)	0.0757 (18)	0.0414 (13)	−0.0124 (14)	0.0130 (12)	−0.0143 (13)
C44	0.0819 (19)	0.0642 (16)	0.0343 (12)	−0.0272 (17)	0.0159 (13)	−0.0018 (12)
C45	0.097 (2)	0.0465 (14)	0.0349 (12)	−0.0048 (15)	0.0069 (15)	0.0030 (10)
C46	0.0603 (15)	0.0441 (12)	0.0369 (11)	0.0019 (12)	0.0111 (11)	−0.0007 (10)

C1—O1	1.404 (3)	C7—H7A	0.9600
C1—O5	1.412 (2)	C7—H7B	0.9600
C1—C2	1.524 (3)	C7—H7C	0.9600
C1—H1	0.9800	O2—H2A	0.8200
C2—O2	1.414 (2)	O3—H3A	0.8200
C2—C3	1.525 (3)	O4—C40	1.433 (2)
C2—H2	0.9800	C40—C41	1.505 (3)
C3—O3	1.426 (2)	C40—H40A	0.9700
C3—C4	1.519 (2)	C40—H40B	0.9700
C3—H3	0.9800	C41—C46	1.383 (3)
C4—O4	1.431 (2)	C41—C42	1.390 (3)
C4—C5	1.535 (3)	C42—C43	1.387 (3)
C4—H4	0.9800	C42—H42	0.9300
C5—O5	1.445 (2)	C43—C44	1.369 (4)
C5—C6	1.508 (3)	C43—H43	0.9300
C5—H5	0.9800	C44—C45	1.384 (4)
C6—H6A	0.9600	C44—H44	0.9300
C6—H6B	0.9600	C45—C46	1.373 (3)
C6—H6C	0.9600	C45—H45	0.9300
O1—C7	1.424 (3)	C46—H46	0.9300
O1—C1—O5	112.30 (17)	H6B—C6—H6C	109.5
O1—C1—C2	107.24 (16)	C1—O1—C7	113.7 (2)
O5—C1—C2	111.33 (16)	O1—C7—H7A	109.5
O1—C1—H1	108.6	O1—C7—H7B	109.5
O5—C1—H1	108.6	H7A—C7—H7B	109.5
C2—C1—H1	108.6	O1—C7—H7C	109.5
O2—C2—C1	110.35 (16)	H7A—C7—H7C	109.5
O2—C2—C3	108.14 (15)	H7B—C7—H7C	109.5
C1—C2—C3	109.60 (15)	C2—O2—H2A	109.5
O2—C2—H2	109.6	C3—O3—H3A	109.5
C1—C2—H2	109.6	C4—O4—C40	115.00 (14)
C3—C2—H2	109.6	O4—C40—C41	108.17 (15)
O3—C3—C4	112.53 (15)	O4—C40—H40A	110.1
O3—C3—C2	108.27 (14)	C41—C40—H40A	110.1
C4—C3—C2	109.53 (15)	O4—C40—H40B	110.1
O3—C3—H3	108.8	C41—C40—H40B	110.1
C4—C3—H3	108.8	H40A—C40—H40B	108.4
C2—C3—H3	108.8	C46—C41—C42	118.4 (2)
O4—C4—C3	108.97 (13)	C46—C41—C40	120.40 (19)
O4—C4—C5	107.88 (14)	C42—C41—C40	121.2 (2)
C3—C4—C5	109.51 (15)	C41—C42—C43	119.8 (2)
O4—C4—H4	110.1	C41—C42—H42	120.1
C3—C4—H4	110.1	C43—C42—H42	120.1
C5—C4—H4	110.1	C44—C43—C42	120.9 (2)
O5—C5—C6	105.68 (15)	C44—C43—H43	119.6
O5—C5—C4	110.25 (15)	C42—C43—H43	119.6
C6—C5—C4	114.22 (17)	C43—C44—C45	119.7 (2)
O5—C5—H5	108.8	C43—C44—H44	120.2
C6—C5—H5	108.8	C45—C44—H44	120.2
C4—C5—H5	108.8	C46—C45—C44	119.4 (3)
C1—O5—C5	114.51 (14)	C46—C45—H45	120.3
C5—C6—H6A	109.5	C44—C45—H45	120.3
C5—C6—H6B	109.5	C45—C46—C41	121.7 (2)
H6A—C6—H6B	109.5	C45—C46—H46	119.1
C5—C6—H6C	109.5	C41—C46—H46	119.1
H6A—C6—H6C	109.5
O1—C1—C2—O2	−173.76 (14)	C4—C5—O5—C1	−57.5 (2)
O5—C1—C2—O2	63.0 (2)	O5—C1—O1—C7	−67.8 (2)
O1—C1—C2—C3	67.3 (2)	C2—C1—O1—C7	169.56 (19)
O5—C1—C2—C3	−55.9 (2)	C3—C4—O4—C40	−132.63 (17)
O2—C2—C3—O3	58.98 (19)	C5—C4—O4—C40	108.58 (18)
C1—C2—C3—O3	179.27 (15)	C4—O4—C40—C41	−168.12 (15)
O2—C2—C3—C4	−64.05 (19)	O4—C40—C41—C46	54.2 (2)
C1—C2—C3—C4	56.2 (2)	O4—C40—C41—C42	−124.9 (2)
O3—C3—C4—O4	65.15 (19)	C46—C41—C42—C43	−2.5 (3)
C2—C3—C4—O4	−174.41 (15)	C40—C41—C42—C43	176.6 (2)
O3—C3—C4—C5	−177.09 (14)	C41—C42—C43—C44	0.5 (3)
C2—C3—C4—C5	−56.64 (19)	C42—C43—C44—C45	2.2 (4)
O4—C4—C5—O5	174.32 (14)	C43—C44—C45—C46	−2.8 (4)
C3—C4—C5—O5	55.90 (18)	C44—C45—C46—C41	0.7 (4)
O4—C4—C5—C6	−66.9 (2)	C42—C41—C46—C45	1.9 (3)
C3—C4—C5—C6	174.69 (16)	C40—C41—C46—C45	−177.2 (2)
O1—C1—O5—C5	−62.6 (2)	C40—O4—C4—H4	−11.7
C2—C1—O5—C5	57.6 (2)	C7—O1—C1—H1	52.3
C6—C5—O5—C1	178.65 (18)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2A···O3i	0.82	2.00	2.813 (2)	172
O3—H3A···O5ii	0.82	2.05	2.799 (2)	151
C7—H7C···Cgiii	0.96	2.89	3.652 (3)	137

Table 1

Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C41–C46 benzyl ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2A⋯O3i	0.82	2.00	2.813 (2)	172
O3—H3A⋯O5ii	0.82	2.05	2.799 (2)	151
C7—H7C⋯Cg iii	0.96	2.89	3.652 (3)	137

Symmetry codes: (i) ; (ii) ; (iii) .