Silyl-directed -Stevens

Mader, M. M., Norrby, P.-O. Computational investigation of the role of fluoride in Tamao oxidations. Chem.- Eur. J. 2002, 8, 5043-5048. Vanecko, J. A., West, F. G. A Novel, Stereoselective Silyl-Directed Stevens [1,2]-Shift of Ammonium Ylides. Org. Lett. 2002,4, 2813-2816. Sun, P., Sun, 0., Weinreb, S. M. Stereoselective Total Syntheses of the Racemic Form and the Natural Enantiomer of the Marine Alkaloid Lepadiformine via a Novel W-Acyliminium lon/Allylsilane Spirocyclization Strategy. J. Org. Chem. 2002, 67, 4337-4345. 

In the laboratory of F.G. West, the stereoselective silyl-directed [1,2]-Stevens rearrangement of ammonium ylides was investigated as a potential key step toward the enantioselective synthesis of various hydroxylated quinolizidines. The dimethylphenylsilyl group served as a surrogate for one of the hydroxyl groups in the product. The Fleming-Tamao oxidation was performed under Denmark s conditions to avoid oxidation of the tertiary amine to the corresponding A/-oxide, and the desired quinolizidine did was obtained in 81% yield. 

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