Synlett 2005(19): 3002-3004  
DOI: 10.1055/s-2005-921891
LETTER
© Georg Thieme Verlag Stuttgart · New York

Highly Regio- and Stereoselective [3+2] Cycloaddition of Carbonyl Ylides with Imines: A Novel Entry to Oxa-Bridged Piperidinone Ring Systems

Sengodagounder Muthusamy*, Janagiraman Krishnamurthi, Eringathodi Suresh
Central Salt & Marine Chemicals Research Institute (CSIR), Bhavnagar - 364 002, Gujarat, India
Fax: +91(278)2567562; e-Mail: muthu@csmcri.org;
Further Information

Publication History

Received 14 September 2005
Publication Date:
27 October 2005 (online)

Abstract

The reaction of α-diazo ketones and N-tosylimines in the presence of a rhodium(II) acetate catalyst led diastereoselectively to the oxa-bridged piperidinone ring systems. The stereochemistry was assigned based on a single-crystal X-ray analysis.

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Crystal data for compound 6a: colorless crystals. C23H25NO4S, M = 411.52, 0.43 × 0.38 × 0.33 mm3, monoclinic, space group Cc, a = 19.5149 (19) Å, b = 14.8813 (14) Å, c = 7.3409 (7) Å, β = 103.786 (2), V = 2070.4 (3) Å3, T = 273 (2) K, R 1 = 0.0349, wR 2 = 0.0943 on observed data, z = 4, D calcd = 1.320 gcm-3, F(000) = 872, Absorption coefficient = 0.186 mm-1, λ = 0.71073 Å, 3050 reflections were collected on a smart apex ccd single crystal CCD diffractometer, 2906 observed reflections [I≥2σ (I)]. The largest difference peak and hole = 0.199 and -0.162 eÅ-3, respectively. The structure was solved by direct methods and refined by full-matrix least squares on F 2 using SHELXL-97 software.

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Crystallographic data for 6a have been deposited with the Cambridge Crystallographic Data Centre as supplementary publication no CCDC-283331. Copies of the data can be obtained free of charge on application to 12, Union Road, Cambridge CB21EZ, UK. [Fax: +44(1223)336033; e-mail: deposit@ccdc.cam.ac.uk].