organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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(2S,4S)-4-Azido-1-benzyl-2-[(S)-2,2-di­methyl-1,3-dioxolan-4-yl]pyrrolidine

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aDepartment of Organic Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, England, and bChemical Crystallography Laboratory, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, England
*Correspondence e-mail: sarah.jenkinson@chem.ox.ac.uk

(Received 8 June 2006; accepted 16 June 2006; online 28 June 2006)

The relative stereochemistry of the title compound, C16H22N4O2, a key inter­mediate in the synthesis of 3-de­oxy imino sugars, was firmly established by X-ray crystallographic analysis. The absolute configuration was inferred from the starting material, D-galactose. There are no unusual crystal packing features.

Comment

The reaction of calcium hydroxide with D-galactose has been shown to generate 3-de­oxy-D-galactono-1,4-lactone, (1), directly (Whistler & BeMiller, 1963[Whistler, R. L. & BeMiller, J. N. (1963). Method Carbohydr. Chem. 2, 483-484.]; Kiliani & Kleeman, 1884[Kiliani, H. & Kleeman, S. (1884). Berichte, 17, 1296-1310.]), the stereochemistry of which has been determined by X-ray crystallographic analysis (Punzo et al. 2006[Punzo, F., Watkin, D. J., Hotchkiss, D. & Fleet, G. W. J. (2006). Acta Cryst. E62, o1344-o1346.]). The 3-de­oxy sugar (1) has great potential as a building block for the synthesis of complex highly functionalized targets. It has been utilized in the synthesis of carnitine (Bols et al., 1992[Bols, M., Lundt, I. & Pedersen, C. (1992). Tetrahedron, 48, 319-324.]) and hydroxy­lated azepanes (Anderson et al., 2000[Anderson, S. M., Ekhart, C., Lundt, I. & Stutz, A. E. (2000). Carbohydr. Res. 326, 22-33.]) and could prove useful in the synthesis of bulgecinines (Bashyal et al., 1987[Bashyal, B. P., Chow, H.-F. & Fleet, G. W. J. (1987). Tetrahedron, 43, 423-430.]; Chavan et al., 2005[Chavan, S. P., Praveen, C., Sharma, P. & Kalkote, U. (2005). Tetrahedron Lett. 46, 439-441.]; Khalaf & Datta, 2004[Khalaf, J. K. & Datta, A. (2004). J. Org. Chem. 69, 387-390.]) and other highly substituted prolines and pyrrolidines. Polyhydroxy­lated nitro­gen heterocycles, known as imino sugars, are an important class of glycosidase inhibitor (Watson et al., 2001[Watson, A. A., Fleet, G. W. J., Asano, N., Molyneux, R. J. & Nash, R. J. (2001). Phytochemistry, 56, 265-295.]; Asano et al., 2000[Asano, N., Nash, R. J., Molyneux, R. J. & Fleet, G. W. J. (2000). Tetrahedron Asymmetry, 11, 1645-1680.]). The title compound, (4), is a key inter­mediate in the synthesis of 2-acetamido-3-de­oxy imino sugars.

[Scheme 1]

The absolute stereochemistry of (4) was known from the use of D-galactose as the starting material. The conversion of (2) to (4) involved nucleophilic dispacement at both C2 and C4 of the sugar. The X-ray crystal structure (Fig. 1[link]) showing the relative configuration of (4) thus establishes that both nucleophilic displacements occurred with inversion of configuration.

There are no unusual bond lengths or angles. As is common with these materials, the azide group is non-linear [N13—N14—N15 = 173.5 (3)°]. There are no short inter­molecular contacts (Fig. 2[link]), nor evidence of ππ inter­actions between the phenyl groups.

[Figure 1]
Figure 1
The title compound with displacement ellipsoids drawn at the 50% probability level. H atoms are shown as spheres of arbitary radius.
[Figure 2]
Figure 2
A projection down the b axis of the title structure. There are no unusually short inter­molecular contacts. Curiously, there are no ππ inter­actions between the phenyl groups.

Experimental

The side-chain diol in (1) was protected as an acetonide and the remaining free hydroxyl group was esterified with methane­sulfonyl chloride. Nucleophilic displacement of the resulting methane­sulfonate ester (2) with sodium azide generated the azide (3) in good yield. Reduction of the lactone to the diol with lithium borohydride and activation of both hydroxyl groups with methane­sulfonyl chloride followed by a double nucleophilic displacement reaction with benzyl­amine generated the 3-de­oxy imino sugar (4) (Chesterton et al., 2006[Chesterton, A. K. S., Jenkinson, S. F., Jones, N. A., Watkin, D. J. & Fleet, G. W. J. (2006). In preparation.]). The final product was recrystallized from dichloro­methane to give colourless needles [m.p. 305–307 K; [α]D18 −48.3 (c 0.76 in acetone)].

Crystal data
  • C16H22N4O2

  • Mr = 302.38

  • Monoclinic, P 21

  • a = 9.6539 (4) Å

  • b = 6.3289 (3) Å

  • c = 13.4942 (7) Å

  • β = 103.577 (2)°

  • V = 801.44 (7) Å3

  • Z = 2

  • Dx = 1.253 Mg m−3

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 150 K

  • Needle, colourless

  • 0.80 × 0.20 × 0.10 mm

Data collection
  • Nonius KappaCCD diffractometer

  • ω scans

  • Absorption correction: multi-scan (DENZO/SCALEPACK, Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]) Tmin = 0.71, Tmax = 0.99

  • 7271 measured reflections

  • 1833 independent reflections

  • 1254 reflections with I > 2σ(I)

  • Rint = 0.064

  • θmax = 30.1°

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.044

  • wR(F2) = 0.100

  • S = 0.86

  • 1833 reflections

  • 199 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(F2) + (0.05P)2 + 0.1P], where P = [max(Fo2,0) + 2Fc2]/3

  • (Δ/σ)max < 0.001

  • Δρmax = 0.41 e Å−3

  • Δρmin = −0.36 e Å−3

In the absence of significant anomalous scattering, Friedel pairs were merged and the absolute configuration assigned from the starting material. The relatively large ratio of minimum to maximum corrections applied in the multi-scan process (1:1.45) reflect changes in the illuminated volume of the crystal. These were kept to a minimum and were taken into account (Görbitz, 1999[Görbitz, C. H. (1999). Acta Cryst. B55, 1090-1098.]) by the multi-scan inter-frame scaling (DENZO/SCALEPACK; Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]). The H atoms were all located in a difference map, but those attached to C 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 = 0.93–0.98 Å and Uiso(H) = 1.2–1.5Ueq(parent atom)], after which the positions were refined with riding constraints.

Data collection: COLLECT (Nonius, 2001[Nonius (2001). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO/SCALEPACK; program(s) used to solve structure: SIR92 (Altomare et al., 1994[Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435-436.]); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003[Betteridge, P. W., Carruthers, J. R., Cooper, R. I., Prout, K. & Watkin, D. J. (2003). J. Appl. Cryst. 36, 1487.]); molecular graphics: CAMERON (Watkin et al., 1996[Watkin, D. J., Prout, C. K. & Pearce, L. J. (1996). CAMERON. Chemical Crystallography Laboratory, Oxford, England.]); software used to prepare material for publication: CRYSTALS.

Supporting information


Computing details top

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.

(2S,4S)-4-Azido-1-benzyl-2-[(S)-2,2-dimethyl-1,3-dioxolan-4-yl]pyrrolidine top
Crystal data top
C16H22N4O2F(000) = 324
Mr = 302.38Dx = 1.253 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
a = 9.6539 (4) ÅCell parameters from 1995 reflections
b = 6.3289 (3) Åθ = 5–30°
c = 13.4942 (7) ŵ = 0.09 mm1
β = 103.577 (2)°T = 150 K
V = 801.44 (7) Å3Plate, colourless
Z = 20.80 × 0.20 × 0.10 mm
Data collection top
Nonius KappaCCD
diffractometer
1254 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.064
ω scansθmax = 30.1°, θmin = 5.3°
Absorption correction: multi-scan
(DENZO/SCALEPACK, Otwinowski & Minor, 1997)
h = 1313
Tmin = 0.71, Tmax = 0.99k = 88
7271 measured reflectionsl = 1818
2489 independent reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.044H-atom parameters constrained
wR(F2) = 0.100 Method = Modified Sheldrick w = 1/[σ2(F2) + (0.05P)2 + 0.1P],
where P = [max(Fo2,0) + 2Fc2]/3
S = 0.86(Δ/σ)max = 0.000154
1833 reflectionsΔρmax = 0.41 e Å3
199 parametersΔρmin = 0.36 e Å3
1 restraint
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.6851 (3)0.6747 (5)0.76546 (19)0.0238
C20.6720 (3)0.4736 (5)0.70332 (19)0.0276
O30.80551 (18)0.4369 (4)0.67623 (13)0.0336
C40.7797 (3)0.4069 (5)0.5685 (2)0.0294
O50.6470 (2)0.5082 (4)0.52745 (14)0.0367
C60.5632 (3)0.4806 (6)0.6004 (2)0.0399
C70.7737 (3)0.1746 (5)0.5447 (2)0.0376
C80.8935 (3)0.5214 (6)0.5299 (2)0.0467
N90.5465 (2)0.7252 (4)0.79036 (16)0.0255
C100.5668 (3)0.7219 (5)0.9024 (2)0.0344
C110.7025 (3)0.5979 (5)0.9430 (2)0.0328
C120.7931 (3)0.6543 (5)0.8683 (2)0.0305
N130.6655 (3)0.3690 (5)0.94096 (19)0.0387
N140.7675 (3)0.2518 (5)0.97347 (19)0.0425
N150.8531 (4)0.1274 (5)1.0014 (3)0.0697
C160.4857 (3)0.9242 (5)0.7467 (2)0.0327
C170.3358 (3)0.9657 (5)0.7593 (2)0.0265
C180.2372 (3)0.8035 (5)0.7527 (2)0.0313
C190.0989 (3)0.8455 (5)0.7596 (2)0.0318
C200.0578 (3)1.0514 (5)0.7727 (2)0.0324
C210.1543 (3)1.2138 (5)0.7796 (2)0.0368
C220.2932 (3)1.1712 (5)0.7730 (2)0.0315
H110.71180.78930.72490.0294*
H210.65110.35680.74510.0325*
H610.49930.60050.59660.0480*
H620.50960.34870.58730.0477*
H710.75920.15570.47220.0539*
H720.86200.11030.57960.0542*
H730.69590.11280.56760.0539*
H810.87550.50770.45640.0718*
H820.98440.45980.56210.0717*
H830.89210.66900.54820.0717*
H1010.57720.86580.92930.0421*
H1020.48500.65370.92040.0423*
H1110.74890.64181.01380.0388*
H1210.84330.78790.88860.0336*
H1220.86100.54300.86610.0339*
H1610.54651.04010.78060.0430*
H1620.48290.92360.67470.0430*
H1810.26540.66460.74400.0374*
H1910.03350.73400.75630.0371*
H2010.03601.08050.77650.0373*
H2110.12751.35230.79070.0440*
H2210.35841.28130.77810.0392*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0183 (14)0.0288 (16)0.0269 (14)0.0004 (13)0.0103 (11)0.0020 (13)
C20.0222 (16)0.0362 (17)0.0263 (14)0.0041 (14)0.0095 (12)0.0022 (15)
O30.0201 (11)0.0552 (14)0.0252 (10)0.0104 (10)0.0048 (8)0.0065 (10)
C40.0233 (16)0.0396 (18)0.0250 (15)0.0041 (15)0.0053 (12)0.0030 (15)
O50.0286 (12)0.0536 (15)0.0272 (10)0.0136 (11)0.0051 (9)0.0042 (11)
C60.0230 (17)0.064 (2)0.0302 (15)0.0077 (17)0.0021 (13)0.0097 (18)
C70.0276 (17)0.046 (2)0.0374 (18)0.0021 (17)0.0031 (14)0.0048 (16)
C80.043 (2)0.057 (2)0.0445 (19)0.0071 (19)0.0189 (15)0.0064 (19)
N90.0248 (13)0.0282 (14)0.0272 (12)0.0031 (11)0.0132 (10)0.0020 (12)
C100.0335 (17)0.044 (2)0.0278 (15)0.0061 (16)0.0122 (13)0.0021 (16)
C110.0321 (18)0.045 (2)0.0211 (16)0.0035 (15)0.0049 (14)0.0036 (14)
C120.0271 (16)0.0321 (17)0.0330 (15)0.0004 (14)0.0087 (13)0.0034 (15)
N130.0337 (16)0.0479 (18)0.0344 (15)0.0019 (15)0.0081 (12)0.0153 (14)
N140.0500 (19)0.0412 (17)0.0327 (15)0.0001 (17)0.0024 (14)0.0039 (14)
N150.070 (2)0.049 (2)0.073 (2)0.0144 (19)0.0167 (19)0.0150 (19)
C160.0327 (18)0.0283 (17)0.0409 (17)0.0017 (15)0.0163 (14)0.0069 (15)
C170.0253 (16)0.0293 (17)0.0253 (14)0.0044 (14)0.0069 (12)0.0036 (14)
C180.0321 (18)0.0260 (16)0.0381 (18)0.0029 (14)0.0129 (15)0.0035 (14)
C190.0239 (17)0.0352 (18)0.0371 (18)0.0049 (15)0.0090 (13)0.0054 (15)
C200.0250 (17)0.0407 (19)0.0333 (17)0.0109 (15)0.0106 (13)0.0084 (15)
C210.041 (2)0.0312 (18)0.0392 (18)0.0092 (17)0.0106 (15)0.0021 (16)
C220.0275 (17)0.0278 (17)0.0391 (17)0.0012 (15)0.0076 (14)0.0033 (15)
Geometric parameters (Å, º) top
C1—C21.513 (4)C10—H1010.977
C1—N91.488 (3)C10—H1020.979
C1—C121.533 (4)C11—C121.524 (4)
C1—H110.980C11—N131.491 (4)
C2—O31.439 (3)C11—H1110.995
C2—C61.533 (3)C12—H1210.981
C2—H210.979C12—H1220.968
O3—C41.429 (3)N13—N141.228 (4)
C4—O51.423 (3)N14—N151.140 (4)
C4—C71.502 (5)C16—C171.519 (4)
C4—C81.507 (4)C16—H1610.982
O5—C61.424 (3)C16—H1620.965
C6—H610.971C17—C181.389 (4)
C6—H620.976C17—C221.389 (4)
C7—H710.964C18—C191.385 (4)
C7—H720.962C18—H1810.936
C7—H730.960C19—C201.386 (5)
C8—H810.970C19—H1910.941
C8—H820.965C20—C211.376 (4)
C8—H830.967C20—H2010.938
N9—C101.479 (3)C21—C221.391 (4)
N9—C161.455 (4)C21—H2110.936
C10—C111.514 (4)C22—H2210.931
C2—C1—N9110.1 (2)C11—C10—H101110.1
C2—C1—C12112.4 (2)N9—C10—H102109.8
N9—C1—C12105.7 (2)C11—C10—H102111.2
C2—C1—H11108.2H101—C10—H102109.7
N9—C1—H11109.6C10—C11—C12102.8 (2)
C12—C1—H11110.8C10—C11—N13108.3 (3)
C1—C2—O3108.3 (2)C12—C11—N13112.8 (3)
C1—C2—C6115.3 (3)C10—C11—H111111.1
O3—C2—C6103.8 (2)C12—C11—H111111.7
C1—C2—H21108.5N13—C11—H111109.9
O3—C2—H21110.0C1—C12—C11104.1 (2)
C6—C2—H21110.7C1—C12—H121111.5
C2—O3—C4109.12 (18)C11—C12—H121109.8
O3—C4—O5105.2 (2)C1—C12—H122110.8
O3—C4—C7109.6 (3)C11—C12—H122110.4
O5—C4—C7111.8 (3)H121—C12—H122110.0
O3—C4—C8108.7 (2)C11—N13—N14114.4 (3)
O5—C4—C8108.1 (3)N13—N14—N15173.5 (3)
C7—C4—C8113.0 (3)N9—C16—C17114.1 (2)
C4—O5—C6106.4 (2)N9—C16—H161108.5
C2—C6—O5104.5 (2)C17—C16—H161107.5
C2—C6—H61111.2N9—C16—H162108.5
O5—C6—H61108.9C17—C16—H162108.1
C2—C6—H62111.2H161—C16—H162110.1
O5—C6—H62110.0C16—C17—C18121.5 (3)
H61—C6—H62110.8C16—C17—C22119.7 (3)
C4—C7—H71109.1C18—C17—C22118.7 (3)
C4—C7—H72109.0C17—C18—C19120.7 (3)
H71—C7—H72110.2C17—C18—H181119.2
C4—C7—H73108.9C19—C18—H181120.1
H71—C7—H73109.8C18—C19—C20119.9 (3)
H72—C7—H73109.9C18—C19—H191120.0
C4—C8—H81109.9C20—C19—H191120.1
C4—C8—H82108.0C19—C20—C21120.1 (3)
H81—C8—H82110.5C19—C20—H201120.1
C4—C8—H83108.8C21—C20—H201119.8
H81—C8—H83109.7C20—C21—C22119.9 (3)
H82—C8—H83109.9C20—C21—H211120.2
C1—N9—C10108.5 (2)C22—C21—H211119.9
C1—N9—C16113.2 (2)C21—C22—C17120.7 (3)
C10—N9—C16111.8 (2)C21—C22—H221119.7
N9—C10—C11105.8 (2)C17—C22—H221119.6
N9—C10—H101110.1
 

References

First citationAltomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435–436.  CrossRef Web of Science IUCr Journals Google Scholar
First citationAnderson, S. M., Ekhart, C., Lundt, I. & Stutz, A. E. (2000). Carbohydr. Res. 326, 22–33.  Web of Science CrossRef PubMed Google Scholar
First citationAsano, N., Nash, R. J., Molyneux, R. J. & Fleet, G. W. J. (2000). Tetrahedron Asymmetry, 11, 1645–1680.  Web of Science CrossRef CAS Google Scholar
First citationBashyal, B. P., Chow, H.-F. & Fleet, G. W. J. (1987). Tetrahedron, 43, 423–430.  CrossRef CAS Web of Science Google Scholar
First citationBetteridge, P. W., Carruthers, J. R., Cooper, R. I., Prout, K. & Watkin, D. J. (2003). J. Appl. Cryst. 36, 1487.  Web of Science CrossRef IUCr Journals Google Scholar
First citationBols, M., Lundt, I. & Pedersen, C. (1992). Tetrahedron, 48, 319–324.  CrossRef CAS Web of Science Google Scholar
First citationChavan, S. P., Praveen, C., Sharma, P. & Kalkote, U. (2005). Tetrahedron Lett. 46, 439–441.  CrossRef CAS Google Scholar
First citationChesterton, A. K. S., Jenkinson, S. F., Jones, N. A., Watkin, D. J. & Fleet, G. W. J. (2006). In preparation.  Google Scholar
First citationGörbitz, C. H. (1999). Acta Cryst. B55, 1090–1098.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationKhalaf, J. K. & Datta, A. (2004). J. Org. Chem. 69, 387–390.  CSD CrossRef PubMed CAS Google Scholar
First citationKiliani, H. & Kleeman, S. (1884). Berichte, 17, 1296-1310.  Google Scholar
First citationNonius (2001). COLLECT. Nonius BV, Delft, The Netherlands.  Google Scholar
First citationOtwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307–326. New York: Academic Press.  Google Scholar
First citationPunzo, F., Watkin, D. J., Hotchkiss, D. & Fleet, G. W. J. (2006). Acta Cryst. E62, o1344–o1346.  CSD CrossRef IUCr Journals Google Scholar
First citationWatkin, D. J., Prout, C. K. & Pearce, L. J. (1996). CAMERON. Chemical Crystallography Laboratory, Oxford, England.  Google Scholar
First citationWatson, A. A., Fleet, G. W. J., Asano, N., Molyneux, R. J. & Nash, R. J. (2001). Phytochemistry, 56, 265–295.  Web of Science CrossRef PubMed CAS Google Scholar
First citationWhistler, R. L. & BeMiller, J. N. (1963). Method Carbohydr. Chem. 2, 483–484.  Google Scholar

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