Samarium Diiodide-Catalyzed Diastereoselective Pinacol Couplings
Helen C. Aspinall, Nicholas Greeves* and Carine Valla
*Donnan and Robert Robinson Laboratories, Department of Chemistry, University of Liverpool, Crown Street, Liverpool, L69 7ZD, UK, Email: ngreevesliv.ac.uk
H. C. Aspinall, N. Greeves, C. Valla, Org. Lett., 2005, 7, 1919-1922.
An intermolecular pinacol coupling of aromatic or aliphatic carbonyl compounds catalyzed by a complex of samarium diiodide (SmI2) with tetraglyme in the presence of Me2SiCl2 and Mg is described. High diastereoselectivity has been achieved in reactions with aliphatic and aromatic aldehydes. De values of up to 99% have been achieved in intramolecular pinacol coupling reactions.
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