SmI2-mediated cross-coupling of nitrones with β-silyl acrylates: synthesis of (+)-australine.

Org Lett

Département de Chimie Moléculaire (SERCO) UMR-5250, ICMG FR-2607, CNRS, Université Joseph Fourier, BP 53, 38041 Grenoble Cedex 09, France.

Published: February 2012

The SmI(2)-mediated cross-coupling of nitrones with β-silyl-α,β-unsaturated esters, followed by zinc reduction, allows an efficient and highly diastereoselective preparation of β-silyl lactams, which are precursors of β-hydroxy lactams through Tamao-Fleming oxidation. By applying the method to a cyclic, carbohydrate-derived nitrone, a new synthesis of (+)-australine has been realized in only 11 steps and in 21% overall yield from L-xylose.

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http://dx.doi.org/10.1021/ol203396sDOI Listing

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View Article and Find Full Text PDF

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