Synthesis 2004(4): 590-594  
DOI: 10.1055/s-2004-815952
PAPER
© Georg Thieme Verlag Stuttgart · New York

Diastereoselective Hydrolysis of α,γ-Substituted γ-Sultones in the Asymmetric Synthesis of γ-Hydroxy Sulfonates

Dieter Enders*, Wacharee Harnying, Gerhard Raabe
Institut für Organische Chemie, Rheinisch-Westfälische Technische Hochschule, Professor-Pirlet-Str. 1, 52074 Aachen, Germany
Fax: +49(241)8092127; e-Mail: Enders@rwth-aachen.de;
Further Information

Publication History

Received 22 December 2003
Publication Date:
03 February 2004 (online)

Abstract

The hydrolysis of enantiopure α,γ-substituted γ-sultones with water under mild conditions leads to α,γ-substituted γ-hydroxy methyl sulfonates in very good yields and excellent diastereo- and enantiomeric excesses (de, ee ≥ 98%). The reaction proceeds via a SN2 mechanism with inversion of configuration at the attacked γ-carbon atom whose absolute configuration was established by X-ray crystallography.

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X-ray Crystallographic Study of 4a: The compound (C10H16O5.5SNa: Mr = 279.29) crystallizes in monoclinic space group C2 (Nr. 5) with cell dimensions of a = 14.019(3), b = 5.6250(11), c = 17.061(3) Å, and β = 110.097(3)º. A cell volume of V = 1263.4(4) Å3 and Z = 4 result in a calculated density of ρcalcd = 1.468 gcm-3. 16500 reflections have been collected in the ω mode at T = 298 K on an Bruker SMART APEX CCD diffractometer employing MoKα-radiation (λ = 0.71073 Å). Data collection covered the range -18 ≤ h £ 18, -7 £ k £ 7, and -22 £ l £ 22 up to θmax = 28.29º; absorption correction with SADABS (µ = 0.301mm-1). The structure has been solved by direct methods as implemented in the Xtal3.7 suite of crystallographic routines [14] where GENSIN has been used to generate the structure-invariant relationships and GENTAN for the general tangent phasing procedure. 1682 observed reflections [I>2σ(I)] have been included in the final full-matrix least-squares refinement on F involving 159 parameters and converging at R(R w ) = 0.031 (0.041, w = 1/[σ2(F) + 0.0004F2]), S = 1.454, and a residual electron density of -0.17/0.33 eÅ-3. The absolute configuration has been determined using Flack’s method and a data set collected using CuKα radiation. Xabs = -0.022(55) [15] for the structure shown in Figure [1] . The hydrogen positions have been calculated in idealized positions. Their Us have been fixed at 1.5 times U of the relevant heavy atom, and no hydrogen parameters have been refined. The asymmetric unit contains 1.5 water molecules which explains deviations between the crystallographic and chemical formulae and densities. The crystal structure of 4a has been deposited as supplementary publication no. CCDC 227543 at the Cambridge Crystallographic Data Centre. Copies of the data can be obtained free of charge on application to CCDC, 12 Union Road, Cambridge CB2 1EZ, UK (fax: +44-1223-336033; e-mail: deposit@ccdc.cam.ac.uk, or http//www.ccdc.cam.ac.uk).

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Hall, S. R.; du Boulay, D. J.; Olthof-Hazekamp, R. Xtal3.7 System, University of Western Australia, 2000.