2,3-Di-C-methyl-D-allono-1,4-lactone

The relative configuration of the title compound, C₈H₁₄O₆, was firmly established by X-ray crystallographic analysis. The absolute configuration was determined by the use of 2-C-methyl-D-ribono-1,4-lactone as the starting material. The crystal structure is stabilized by O—H...O hydrogen bonds, with each mol­ecule acting as a donor and an acceptor for five hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 150 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.024
• wR factor = 0.059
• Data-to-parameter ratio = 9.3

checkCIF/PLATON results

No syntax errors found



Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.810     0.990
            Tmin(prime) and Tmax expected:      0.964     0.988
            RR(prime) =      0.839
            Please check that your absorption correction is appropriate.
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.84

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.51
           From the CIF: _reflns_number_total               1185
           Count of symmetry unique reflns         1213
           Completeness (_total/calc)             97.69%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present         no
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C1     = .          R
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C2     = .          R
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C5     = .          R
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C6     = .          R
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   6 ALERT level G = General alerts; check

   4 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Carbohydrates are one of the most varied cheap chiral building blocks (Lichtenthaler & Peters, 2004) available. Currently, there are very limited examples of di-branched carbohydrates reported. Examples of sugars that contain two carbon branches in the literature include 2,4-dimethyl-3,4-O-isopropylidene-L-arabinono-1,5-lactone (Booth et al. 2007a) and various protected forms of 3,5-Di-C-methyl-mannono and glucono lactone (Booth, Watkin et al., 2007; Booth et al., 2007a,b,c).

The Kiliani ascension on ketoses and deoxy ketoses has proved a valuable route towards branched sugars (Hotchkiss et al. 2004;2006, Soengas et al., 2005, Jones, Watkin et al. 2007). Branched sugars still remains a relatively unstudied class of compounds but recent biological results have indicated they could have a potential use as therapeutics (Mitchell et al. 2007).

The crystal structure of the title compound (Fig. 1) exists as a three-dimensionally hydrogen bonded lattice with each molecule acting as a donor and an acceptor for 5 hydrogen bonds. One of the hydrogen bonds, from O8—H11, is bifurcated (Fig. 2).

Related literature

For related literature, see: Jones, Curran et al. (2007); Jones, Watkin et al. (2007); Mitchell et al. (2007); Hotchkiss et al. (2006, 2004); Soengas et al. (2005).

For related literature, see: Booth et al. (2007, 2007a, 2007b, 2007c); Görbitz (1999); Lichtenthaler & Peters (2004).

S2. Experimental

Treatment of 1-deoxy-3-C-methyl-D-psicose 1 (see Fig. 3) (Jones, Curran et al. 2007) derived from 2-C-methyl-D-ribono-1,4-lactone (Hotchkiss et al., 2006), with sodium cyanide, gave a mixture of 2,6-anhydro derivative 2 and lactone 3 Deprotection of lactone 3 gave an equilibrium of 1,5-lactone 4 and 1,4-lactone 5 in which 2,3-C-dimethyl-D-allono-lactone exists as 2,3-C-dimethyl-D-allono-1,4-lactone 5 in the crystalline state. X-Ray crystallographic analysis shows that the structure is the title compound 5 removing ambiguities as to the stereochemistry at the new C-2 chiral centre. The title compound was crystallized from a mixture of cyclohexane and ethyl acetate; m.p. 426–428 K; [α]_D²² +66.8 (c, 0.65 in methanol).

S3. Refinement

In the absence of significant anomalous scattering, Friedel pairs were merged and the absolute configuration was assigned by the starting material.

The relatively large ratio of minimum to maximum corrections applied in the multiscan process (1:1.22) reflect changes in the illuminated volume of the crystal. Changes in illuminated volume were kept to a minimum, and were taken into account (Görbitz, 1999) by the multi-scan inter-frame scaling (DENZO/SCALEPACK, Otwinowski & Minor, 1997).

The H atoms were all located in a difference map, but those attached to carbon atoms were repositioned geometrically. The H atoms were initially refined with soft restraints on the bond lengths and angles to regularize their geometry (C—H in the range 0.93–0.98, O—H = 0.82 Å) and U_iso(H) (in the range 1.2–1.5 times U_eq of the parent atom), after which the positions were refined with riding constraints.

Computing details

Data collection: COLLECT (Nonius, 2001); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK; program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: CAMERON (Watkin et al., 1996); software used to prepare material for publication: CRYSTALS.

Figures

	Fig. 1. The title compound with displacement ellipsoids drawn at the 50% probability level. H atoms are shown as spheres of arbitary radius.
	Fig. 2. Packing diagram showing the title compound projected along the a-axis.
	Fig. 3. The reaction scheme.

2,3-C-Dimethyl-D-allono-1,4-lactone

Crystal data

C8H14O6	F(000) = 220
Mr = 206.20	Dx = 1.398 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 1103 reflections
a = 6.1387 (2) Å	θ = 5–27°
b = 7.4088 (3) Å	µ = 0.12 mm^−1
c = 10.8142 (3) Å	T = 150 K
β = 94.996 (2)°	Plate, colourless
V = 489.97 (3) Å^3	0.30 × 0.20 × 0.10 mm
Z = 2

Data collection

Nonius KappaCCD diffractometer	1151 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.022
ω scans	θmax = 27.5°, θmin = 5.5°
Absorption correction: multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997)	h = −7→7
Tmin = 0.81, Tmax = 0.99	k = −9→8
4427 measured reflections	l = −14→13
1185 independent reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.024	H-atom parameters constrained
wR(F^2) = 0.059	w = 1/[σ^2(F^2) + 0.11P], where P = [max(Fo^2,0) + 2Fc^2]/3
S = 0.98	(Δ/σ)max = 0.000341
1185 reflections	Δρmax = 0.22 e Å^−3
127 parameters	Δρmin = −0.15 e Å^−3
1 restraint

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
C1	0.8416 (2)	0.4263 (2)	0.78654 (13)	0.0150
C2	0.7563 (2)	0.3296 (2)	0.66461 (13)	0.0162
C3	0.6629 (2)	0.4883 (2)	0.58761 (13)	0.0167
O4	0.60598 (17)	0.62177 (17)	0.66215 (9)	0.0191
C5	0.6621 (2)	0.5717 (2)	0.79221 (12)	0.0142
C6	0.7150 (2)	0.7452 (2)	0.86458 (13)	0.0167
C7	0.5125 (2)	0.8654 (2)	0.86070 (13)	0.0183
O8	0.55256 (18)	1.02775 (17)	0.92964 (10)	0.0217
O9	0.79185 (17)	0.69964 (18)	0.98862 (9)	0.0202
O10	0.63373 (19)	0.49872 (19)	0.47585 (9)	0.0248
O11	0.57031 (17)	0.22808 (17)	0.69455 (9)	0.0201
C12	0.9154 (3)	0.2152 (3)	0.60015 (15)	0.0271
O13	0.83413 (16)	0.30793 (17)	0.88832 (9)	0.0184
C14	1.0685 (2)	0.5052 (2)	0.77945 (14)	0.0213
H51	0.5313	0.5108	0.8209	0.0186*
H61	0.8324	0.8105	0.8255	0.0186*
H71	0.4019	0.7962	0.9000	0.0210*
H72	0.4647	0.8908	0.7734	0.0213*
H121	0.8351	0.1608	0.5271	0.0417*
H122	0.9737	0.1226	0.6570	0.0412*
H123	1.0318	0.2899	0.5717	0.0413*
H141	1.1107	0.5686	0.8566	0.0333*
H142	1.1713	0.4101	0.7692	0.0338*
H143	1.0615	0.5863	0.7091	0.0340*
H4	0.6813	0.6440	1.0171	0.0323*
H10	0.9644	0.2852	0.9245	0.0307*
H11	0.6169	1.0978	0.8849	0.0359*
H14	0.5063	0.1748	0.6320	0.0313*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0152 (6)	0.0146 (7)	0.0149 (6)	0.0006 (6)	0.0000 (5)	0.0030 (5)
C2	0.0178 (7)	0.0149 (7)	0.0159 (6)	0.0015 (6)	0.0015 (5)	0.0011 (5)
C3	0.0181 (7)	0.0155 (7)	0.0163 (6)	−0.0009 (6)	−0.0004 (5)	0.0002 (6)
O4	0.0258 (5)	0.0159 (5)	0.0145 (5)	0.0043 (4)	−0.0041 (4)	0.0000 (4)
C5	0.0155 (6)	0.0141 (7)	0.0124 (6)	0.0003 (5)	−0.0023 (5)	0.0007 (5)
C6	0.0180 (6)	0.0155 (7)	0.0163 (6)	−0.0042 (6)	0.0004 (5)	−0.0007 (6)
C7	0.0238 (7)	0.0128 (7)	0.0181 (6)	−0.0004 (6)	0.0012 (5)	−0.0017 (6)
O8	0.0309 (6)	0.0132 (5)	0.0220 (5)	−0.0040 (5)	0.0076 (4)	−0.0024 (4)
O9	0.0211 (5)	0.0222 (6)	0.0162 (5)	−0.0057 (5)	−0.0046 (4)	−0.0002 (4)
O10	0.0349 (6)	0.0247 (6)	0.0141 (5)	0.0031 (5)	−0.0022 (4)	0.0021 (5)
O11	0.0243 (5)	0.0180 (5)	0.0176 (5)	−0.0074 (5)	−0.0006 (4)	−0.0012 (4)
C12	0.0317 (8)	0.0262 (9)	0.0238 (7)	0.0093 (7)	0.0051 (6)	−0.0030 (7)
O13	0.0171 (5)	0.0197 (5)	0.0177 (5)	−0.0014 (4)	−0.0030 (4)	0.0074 (4)
C14	0.0149 (7)	0.0248 (8)	0.0240 (7)	−0.0026 (6)	0.0003 (5)	0.0029 (7)

Geometric parameters (Å, º)

C1—C2	1.5509 (19)	C6—H61	0.992
C1—C5	1.547 (2)	C7—O8	1.4253 (17)
C1—O13	1.4110 (17)	C7—H71	0.977
C1—C14	1.518 (2)	C7—H72	0.982
C2—C3	1.523 (2)	O8—H11	0.832
C2—O11	1.4277 (17)	O9—H4	0.873
C2—C12	1.509 (2)	O11—H14	0.850
C3—O4	1.3413 (18)	C12—H121	0.981
C3—O10	1.2087 (17)	C12—H122	0.970
O4—C5	1.4663 (16)	C12—H123	0.974
C5—C6	1.5249 (19)	O13—H10	0.876
C5—H51	0.994	C14—H141	0.972
C6—C7	1.527 (2)	C14—H142	0.958
C6—O9	1.4232 (17)	C14—H143	0.968
C2—C1—C5	99.57 (11)	C5—C6—H61	108.8
C2—C1—O13	110.17 (12)	C7—C6—H61	108.9
C5—C1—O13	109.28 (11)	O9—C6—H61	108.9
C2—C1—C14	112.23 (12)	C6—C7—O8	112.03 (12)
C5—C1—C14	113.17 (13)	C6—C7—H71	106.1
O13—C1—C14	111.78 (11)	O8—C7—H71	108.0
C1—C2—C3	101.06 (12)	C6—C7—H72	108.2
C1—C2—O11	105.55 (10)	O8—C7—H72	111.4
C3—C2—O11	105.10 (11)	H71—C7—H72	111.0
C1—C2—C12	117.88 (13)	C7—O8—H11	106.9
C3—C2—C12	114.12 (12)	C6—O9—H4	103.9
O11—C2—C12	111.80 (14)	C2—O11—H14	112.8
C2—C3—O4	110.23 (11)	C2—C12—H121	107.6
C2—C3—O10	127.72 (14)	C2—C12—H122	108.8
O4—C3—O10	122.01 (14)	H121—C12—H122	110.6
C3—O4—C5	109.77 (11)	C2—C12—H123	110.4
C1—C5—O4	104.29 (10)	H121—C12—H123	108.1
C1—C5—C6	119.14 (12)	H122—C12—H123	111.2
O4—C5—C6	107.52 (11)	C1—O13—H10	112.2
C1—C5—H51	107.1	C1—C14—H141	108.7
O4—C5—H51	106.6	C1—C14—H142	109.8
C6—C5—H51	111.4	H141—C14—H142	108.9
C5—C6—C7	109.92 (11)	C1—C14—H143	107.5
C5—C6—O9	108.80 (11)	H141—C14—H143	111.4
C7—C6—O9	111.49 (11)	H142—C14—H143	110.5

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O9—H4···O8^i	0.87	1.81	2.683 (2)	178
O13—H10···O9^ii	0.88	1.81	2.675 (2)	169
O8—H11···O13^iii	0.83	2.05	2.762 (2)	144
O11—H14···O10^iv	0.85	1.90	2.729 (2)	163
O8—H11···O11^iii	0.83	2.27	2.954 (2)	140

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