2-C-Cyclo­hexyl-2,3-O-isopropyl­idene­erythrofuran­ose

Robinson, T.V.; Taylor, D.K.; Tiekink, E.R.T.

doi:10.1107/S1600536809048557

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 65| Part 12| December 2009| Page o3124

doi:10.1107/S1600536809048557

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2-C-Cyclohexyl-2,3-O-isopropylideneerythrofuranose

Tony V. Robinson,^a Dennis K. Taylor ^b ‡ and Edward R. T. Tiekink ^c ^*

^aDiscipline of Chemistry, University of Adelaide, 5005 South Australia, Australia, ^bDiscipline of Wine and Horticulture, University of Adelaide, Waite Campus, Glen, Osmond 5064, South Australia, Australia, and ^cDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
^*Correspondence e-mail: edward.tiekink@gmail.com

(Received 15 November 2009; accepted 16 November 2009; online 21 November 2009)

In the title compound, C₁₃H₂₂O₄, the acetonide ring adopts an envelope conformation with one of the O atoms as the flap atom, whereas a twisted conformation is found for the furanose ring. Centrosymmetric eight-membered {⋯OCOH}₂ synthons involving the hydroxy H and acetonide O atoms are found in the crystal structure. These are linked into a supramolecular chain in the a-axis direction via C—H⋯O contacts.

Related literature

For the dihydroxylation of the olefin portion of 1,2-dioxines, see: Robinson et al. (2006 , 2009 ); Valente et al. (2009 ); Pedersen et al. (2009 ).

Experimental

Crystal data

C₁₃H₂₂O₄
M_r = 242.31
Triclinic, $[P \overline 1]$
a = 5.454 (3) Å
b = 9.908 (3) Å
c = 12.442 (5) Å
α = 93.29 (3)°
β = 94.95 (4)°
γ = 102.94 (3)°
V = 650.8 (5) Å³
Z = 2
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 153 K
0.24 × 0.15 × 0.13 mm

Data collection

Rigaku AFC12K/SATURN724 diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ) T_min = 0.789, T_max = 1
4992 measured reflections
2224 independent reflections
2064 reflections with I > 2σ(I)
R_int = 0.020

Refinement

R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.124
S = 1.09
2224 reflections
156 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.18 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O4—H40⋯O3ⁱ	0.84	1.95	2.787 (2)	173
C2—H2⋯O1ⁱⁱ	1.00	2.43	3.350 (3)	152
Symmetry codes: (i) -x+2, -y+1, -z+2; (ii) x+1, y, z.

Data collection: CrystalClear (Rigaku/MSC, 2005 ); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2006 ); software used to prepare material for publication: publCIF (Westrip, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809048557/hg2594sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809048557/hg2594Isup2.hkl

checkCIF report

Comment top

Recently we examined the dihydroxylation of the olefin portion of 1,2-dioxines, which provided access to a range of polyhydroxylated core structures upon selective manipulation of the peroxide linkage (Robinson et al., 2006; Robinson et al., 2009; Valente et al., 2009). This methodology was extended to include the synthesis of erythrono-γ-lactones (Pedersen et al., 2009), during the course of which the title compound, (I), was prepared.

The molecular structure of (I), Fig. 1, comprises two fused five-membered rings linked by the C2—C3 bond. The acetonide ring adopts an envelope conformation with the O2 atom being the flap atom. A twisted conformation is found for the furanose ring whereby the O3 atom is endo and the C4 atom is exo. The cyclohexyl group is in the chair conformation. The crystal structure comprises centrosymmetric dimers held by {···OCOH}₂ synthons arising from the interaction between the O4-hydroxyl group and the ether-O3 atom, Fig. 2 and Table 1. The resultant eight-membered ring has an elongated chair conformation. The dimeric aggregates are linked into supramolecular chains via C—H···O interactions, Fig. 2 and Table 1. The topology of the supramolecular chain is linear, and is aligned along the a direction.

Related literature top

For the dihydroxylation of the olefin portion of 1,2-dioxines, see: Robinson et al. (2006, 2009); Valente et al. (2009); Pedersen et al. (2009).

Experimental top

For full synthetic procedures and characterization data see Pedersen et al. (2009) and Robinson et al. (2009). To a stirred solution of Co(salen)₂ (27 mg, 0.08 mmol) in THF (5 ml) at ambient temperature was added (3aR,7aS)-3a-cyclohexyl-tetrahydro-2,2-dimethyl-[1,3]dioxolo[4,5-d][1,2]dioxine (803 mg, 3.31 mmol). The reaction left to stir until complete by TLC (~16 h). All volatiles were removed in vacuo giving a crude mixture of regioisomers in a 43:57 ratio. The isomers were completely separated by flash chromatography giving a combined total yield of 779 mg (97%). Compound (I) was isolated as a colourless solid (337 mg), and the pure material was recrystallized by slowly evaporating a 1:1 mixture of dichloromethane/heptane to give colourless prisms, m. pt. 391–394 K. The compound was found to exist solely in its cyclic hemi-acetal form(s) both as a solid indicated by IR (absence of carbonyl signal), and in CDCl₃ solution which revealed a 94:6 anomeric ratio.

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2005); cell refinement: CrystalClear (Rigaku/MSC, 2005); data reduction: CrystalClear (Rigaku/MSC, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2009).

Figures top

	Fig. 1. Molecular structure of (I) showing atom-labelling scheme and displacement ellipsoids at the 50% probability level.
	Fig. 2. Supramolecular chain formation along the a axis in (I) mediated by O—H···O hydrogen bonds (orange dashed lines) and C—H···O contacts (blue dashed lines).

2-C-Cyclohexyl-2,3-O-isopropylideneerythrofuranose top

Crystal data top

C₁₃H₂₂O₄	Z = 2
M_r = 242.31	F(000) = 264
Triclinic, P1	D_x = 1.237 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 5.454 (3) Å	Cell parameters from 657 reflections
b = 9.908 (3) Å	θ = 2.1–30.2°
c = 12.442 (5) Å	µ = 0.09 mm⁻¹
α = 93.29 (3)°	T = 153 K
β = 94.95 (4)°	Needle, colourless
γ = 102.94 (3)°	0.24 × 0.15 × 0.13 mm
V = 650.8 (5) Å³

Data collection top

Rigaku AFC12K/SATURN724 diffractometer	2224 independent reflections
Radiation source: fine-focus sealed tube	2064 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.020
ω scans	θ_max = 25.0°, θ_min = 2.1°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −6→5
T_min = 0.789, T_max = 1	k = −11→11
4992 measured reflections	l = −14→14

Refinement top

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.124	H-atom parameters constrained
S = 1.09	w = 1/[σ²(F_o²) + (0.066P)² + 0.1734P] where P = (F_o² + 2F_c²)/3
2224 reflections	(Δ/σ)_max < 0.001
156 parameters	Δρ_max = 0.18 e Å⁻³
1 restraint	Δρ_min = −0.20 e Å⁻³

Crystal data top

C₁₃H₂₂O₄	γ = 102.94 (3)°
M_r = 242.31	V = 650.8 (5) Å³
Triclinic, P1	Z = 2
a = 5.454 (3) Å	Mo Kα radiation
b = 9.908 (3) Å	µ = 0.09 mm⁻¹
c = 12.442 (5) Å	T = 153 K
α = 93.29 (3)°	0.24 × 0.15 × 0.13 mm
β = 94.95 (4)°

Data collection top

Rigaku AFC12K/SATURN724 diffractometer	2224 independent reflections
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	2064 reflections with I > 2σ(I)
T_min = 0.789, T_max = 1	R_int = 0.020
4992 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	1 restraint
wR(F²) = 0.124	H-atom parameters constrained
S = 1.09	Δρ_max = 0.18 e Å⁻³
2224 reflections	Δρ_min = −0.20 e Å⁻³
156 parameters

Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
O1	0.69690 (18)	0.26256 (11)	0.70713 (8)	0.0281 (3)
O2	1.0523 (2)	0.34466 (12)	0.62499 (9)	0.0352 (3)
O3	0.9937 (2)	0.48884 (11)	0.85907 (9)	0.0377 (3)
O4	1.0310 (3)	0.31604 (12)	0.97416 (9)	0.0439 (4)
H4O	1.0281	0.3703	1.0282	0.066*
C1	0.7854 (3)	0.33328 (17)	0.61509 (12)	0.0312 (4)
C2	1.1367 (3)	0.33878 (16)	0.73567 (13)	0.0320 (4)
H2	1.2783	0.2898	0.7425	0.038*
C3	0.9031 (3)	0.25734 (15)	0.78511 (12)	0.0270 (4)
C4	0.8885 (3)	0.35109 (16)	0.88634 (12)	0.0327 (4)
H4	0.7088	0.3415	0.9019	0.039*
C5	1.2089 (3)	0.47939 (18)	0.80110 (15)	0.0410 (4)
H5A	1.3609	0.4853	0.8524	0.049*
H5B	1.2450	0.5556	0.7526	0.049*
C6	0.7237 (3)	0.47484 (18)	0.61632 (14)	0.0366 (4)
H6A	0.5397	0.4637	0.6085	0.055*
H6B	0.7959	0.5243	0.5562	0.055*
H6C	0.7954	0.5282	0.6850	0.055*
C7	0.6697 (4)	0.2440 (2)	0.51267 (14)	0.0446 (5)
H7A	0.4850	0.2278	0.5085	0.067*
H7B	0.7193	0.1549	0.5134	0.067*
H7C	0.7299	0.2916	0.4497	0.067*
C8	0.9010 (3)	0.10690 (15)	0.80714 (12)	0.0281 (4)
H8	1.0454	0.1086	0.8629	0.034*
C9	0.9368 (3)	0.01889 (16)	0.70736 (14)	0.0353 (4)
H9A	0.7968	0.0159	0.6504	0.042*
H9B	1.0973	0.0623	0.6788	0.042*
C10	0.9421 (3)	−0.12889 (17)	0.73441 (16)	0.0410 (4)
H10A	0.9581	−0.1844	0.6677	0.049*
H10B	1.0915	−0.1265	0.7863	0.049*
C11	0.7028 (3)	−0.19803 (17)	0.78331 (14)	0.0363 (4)
H11A	0.5557	−0.2117	0.7280	0.044*
H11B	0.7179	−0.2905	0.8053	0.044*
C12	0.6588 (3)	−0.11062 (17)	0.88099 (14)	0.0376 (4)
H12A	0.7936	−0.1083	0.9402	0.045*
H12B	0.4948	−0.1539	0.9067	0.045*
C13	0.6576 (3)	0.03762 (17)	0.85399 (13)	0.0343 (4)
H13A	0.6391	0.0929	0.9204	0.041*
H13B	0.5107	0.0361	0.8010	0.041*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0218 (5)	0.0379 (6)	0.0252 (6)	0.0082 (4)	0.0014 (4)	0.0048 (4)
O2	0.0277 (6)	0.0454 (7)	0.0345 (6)	0.0098 (5)	0.0089 (5)	0.0062 (5)
O3	0.0485 (7)	0.0307 (6)	0.0335 (7)	0.0112 (5)	−0.0019 (5)	−0.0002 (5)
O4	0.0662 (8)	0.0383 (7)	0.0279 (6)	0.0212 (6)	−0.0115 (6)	−0.0033 (5)
C1	0.0266 (8)	0.0414 (9)	0.0262 (8)	0.0078 (6)	0.0047 (6)	0.0051 (6)
C2	0.0240 (8)	0.0352 (8)	0.0373 (9)	0.0082 (6)	0.0009 (6)	0.0041 (7)
C3	0.0234 (7)	0.0332 (8)	0.0250 (8)	0.0095 (6)	−0.0009 (6)	−0.0001 (6)
C4	0.0413 (9)	0.0312 (8)	0.0264 (8)	0.0125 (7)	−0.0015 (7)	0.0008 (6)
C5	0.0334 (9)	0.0370 (9)	0.0483 (10)	0.0027 (7)	−0.0044 (7)	0.0023 (8)
C6	0.0343 (9)	0.0440 (10)	0.0337 (9)	0.0121 (7)	0.0037 (7)	0.0100 (7)
C7	0.0490 (11)	0.0548 (11)	0.0272 (9)	0.0082 (8)	−0.0003 (8)	0.0005 (8)
C8	0.0260 (8)	0.0313 (8)	0.0272 (8)	0.0084 (6)	0.0005 (6)	0.0000 (6)
C9	0.0347 (9)	0.0351 (9)	0.0373 (9)	0.0079 (7)	0.0124 (7)	−0.0006 (7)
C10	0.0407 (10)	0.0329 (9)	0.0506 (11)	0.0097 (7)	0.0137 (8)	−0.0047 (7)
C11	0.0380 (9)	0.0314 (8)	0.0378 (9)	0.0050 (7)	0.0042 (7)	−0.0006 (7)
C12	0.0432 (10)	0.0365 (9)	0.0340 (9)	0.0088 (7)	0.0070 (7)	0.0061 (7)
C13	0.0369 (9)	0.0369 (9)	0.0319 (9)	0.0119 (7)	0.0107 (7)	0.0027 (7)

Geometric parameters (Å, º) top

O1—C3	1.4328 (18)	C7—H7A	0.9800
O1—C1	1.4392 (19)	C7—H7B	0.9800
O2—C2	1.423 (2)	C7—H7C	0.9800
O2—C1	1.429 (2)	C8—C9	1.528 (2)
O3—C4	1.429 (2)	C8—C13	1.531 (2)
O3—C5	1.447 (2)	C8—H8	1.0000
O4—C4	1.392 (2)	C9—C10	1.527 (2)
O4—H4O	0.8399	C9—H9A	0.9900
C1—C7	1.512 (2)	C9—H9B	0.9900
C1—C6	1.513 (2)	C10—C11	1.526 (2)
C2—C5	1.526 (2)	C10—H10A	0.9900
C2—C3	1.544 (2)	C10—H10B	0.9900
C2—H2	1.0000	C11—C12	1.519 (2)
C3—C8	1.529 (2)	C11—H11A	0.9900
C3—C4	1.540 (2)	C11—H11B	0.9900
C4—H4	1.0000	C12—C13	1.527 (2)
C5—H5A	0.9900	C12—H12A	0.9900
C5—H5B	0.9900	C12—H12B	0.9900
C6—H6A	0.9800	C13—H13A	0.9900
C6—H6B	0.9800	C13—H13B	0.9900
C6—H6C	0.9800

C3—O1—C1	111.24 (11)	C1—C7—H7B	109.5
C2—O2—C1	108.79 (12)	H7A—C7—H7B	109.5
C4—O3—C5	105.95 (12)	C1—C7—H7C	109.5
C4—O4—H4O	108.8	H7A—C7—H7C	109.5
O2—C1—O1	105.26 (12)	H7B—C7—H7C	109.5
O2—C1—C7	108.62 (14)	C9—C8—C3	113.25 (13)
O1—C1—C7	109.15 (13)	C9—C8—C13	109.62 (13)
O2—C1—C6	111.35 (13)	C3—C8—C13	111.20 (12)
O1—C1—C6	110.47 (13)	C9—C8—H8	107.5
C7—C1—C6	111.76 (14)	C3—C8—H8	107.5
O2—C2—C5	114.39 (14)	C13—C8—H8	107.5
O2—C2—C3	104.95 (12)	C10—C9—C8	111.22 (14)
C5—C2—C3	104.74 (13)	C10—C9—H9A	109.4
O2—C2—H2	110.8	C8—C9—H9A	109.4
C5—C2—H2	110.8	C10—C9—H9B	109.4
C3—C2—H2	110.8	C8—C9—H9B	109.4
O1—C3—C8	110.40 (12)	H9A—C9—H9B	108.0
O1—C3—C4	108.10 (12)	C11—C10—C9	111.32 (14)
C8—C3—C4	114.24 (13)	C11—C10—H10A	109.4
O1—C3—C2	103.39 (12)	C9—C10—H10A	109.4
C8—C3—C2	116.55 (12)	C11—C10—H10B	109.4
C4—C3—C2	103.27 (12)	C9—C10—H10B	109.4
O4—C4—O3	111.08 (13)	H10A—C10—H10B	108.0
O4—C4—C3	109.45 (12)	C12—C11—C10	111.32 (14)
O3—C4—C3	104.59 (13)	C12—C11—H11A	109.4
O4—C4—H4	110.5	C10—C11—H11A	109.4
O3—C4—H4	110.5	C12—C11—H11B	109.4
C3—C4—H4	110.5	C10—C11—H11B	109.4
O3—C5—C2	106.01 (13)	H11A—C11—H11B	108.0
O3—C5—H5A	110.5	C11—C12—C13	111.60 (14)
C2—C5—H5A	110.5	C11—C12—H12A	109.3
O3—C5—H5B	110.5	C13—C12—H12A	109.3
C2—C5—H5B	110.5	C11—C12—H12B	109.3
H5A—C5—H5B	108.7	C13—C12—H12B	109.3
C1—C6—H6A	109.5	H12A—C12—H12B	108.0
C1—C6—H6B	109.5	C12—C13—C8	111.60 (13)
H6A—C6—H6B	109.5	C12—C13—H13A	109.3
C1—C6—H6C	109.5	C8—C13—H13A	109.3
H6A—C6—H6C	109.5	C12—C13—H13B	109.3
H6B—C6—H6C	109.5	C8—C13—H13B	109.3
C1—C7—H7A	109.5	H13A—C13—H13B	108.0

C2—O2—C1—O1	−24.16 (15)	C2—C3—C4—O4	−89.45 (15)
C2—O2—C1—C7	−140.95 (13)	O1—C3—C4—O3	−79.48 (14)
C2—O2—C1—C6	95.56 (15)	C8—C3—C4—O3	157.20 (12)
C3—O1—C1—O2	12.78 (15)	C2—C3—C4—O3	29.63 (14)
C3—O1—C1—C7	129.21 (14)	C4—O3—C5—C2	34.96 (16)
C3—O1—C1—C6	−107.53 (14)	O2—C2—C5—O3	99.37 (16)
C1—O2—C2—C5	−88.63 (16)	C3—C2—C5—O3	−14.97 (16)
C1—O2—C2—C3	25.58 (15)	O1—C3—C8—C9	62.51 (16)
C1—O1—C3—C8	−122.93 (13)	C4—C3—C8—C9	−175.42 (12)
C1—O1—C3—C4	111.46 (14)	C2—C3—C8—C9	−55.00 (17)
C1—O1—C3—C2	2.43 (14)	O1—C3—C8—C13	−61.44 (16)
O2—C2—C3—O1	−16.78 (14)	C4—C3—C8—C13	60.62 (17)
C5—C2—C3—O1	104.03 (13)	C2—C3—C8—C13	−178.95 (12)
O2—C2—C3—C8	104.51 (14)	C3—C8—C9—C10	178.09 (12)
C5—C2—C3—C8	−134.68 (14)	C13—C8—C9—C10	−57.09 (17)
O2—C2—C3—C4	−129.38 (12)	C8—C9—C10—C11	56.64 (19)
C5—C2—C3—C4	−8.57 (15)	C9—C10—C11—C12	−54.5 (2)
C5—O3—C4—O4	77.45 (16)	C10—C11—C12—C13	53.94 (19)
C5—O3—C4—C3	−40.52 (15)	C11—C12—C13—C8	−55.52 (18)
O1—C3—C4—O4	161.44 (12)	C9—C8—C13—C12	56.55 (17)
C8—C3—C4—O4	38.13 (18)	C3—C8—C13—C12	−177.46 (12)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O4—H40···O3ⁱ	0.84	1.95	2.787 (2)	173
C2—H2···O1ⁱⁱ	1.00	2.43	3.350 (3)	152

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

Experimental details

Crystal data
Chemical formula	C₁₃H₂₂O₄
M_r	242.31
Crystal system, space group	Triclinic, P1
Temperature (K)	153
a, b, c (Å)	5.454 (3), 9.908 (3), 12.442 (5)
α, β, γ (°)	93.29 (3), 94.95 (4), 102.94 (3)
V (Å³)	650.8 (5)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.24 × 0.15 × 0.13

Data collection
Diffractometer	Rigaku AFC12K/SATURN724 diffractometer
Absorption correction	Multi-scan (ABSCOR; Higashi, 1995)
T_min, T_max	0.789, 1
No. of measured, independent and observed [I > 2σ(I)] reflections	4992, 2224, 2064
R_int	0.020
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.124, 1.09
No. of reflections	2224
No. of parameters	156
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.18, −0.20

Computer programs: CrystalClear (Rigaku/MSC, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2006), publCIF (Westrip, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O4—H40···O3ⁱ	0.84	1.95	2.787 (2)	173
C2—H2···O1ⁱⁱ	1.00	2.43	3.350 (3)	152

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

Footnotes

‡Additional correspondence author, e-mail: dennis.taylor@adelaide.edu.au.

Acknowledgements

We are grateful to the Australian Research Council for financial support. TVR thanks the Commonwealth Government of Australia for a postgraduate scholarship.

References

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