T. Nishi, K. Nakajima, Y. Iio
Aug 1, 1998
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0
Influential Citations
15
Citations
Journal
Tetrahedron-asymmetry
Abstract
Abstract We report simple and efficient methods for the preparation of enantiomerically pure spiro[benzo[ c ]thiophene-1(3 H ),4′-piperidine]-(2 S )-oxide ( S )- 1 , a key intermediate for the synthesis of tachykinin receptor antagonist, by resolution and asymmetric sulfoxidation. Racemic ( RS )- 1 can be resolved with ( S )-(+)-mandelic acid in acetonitrile to give ( S )- 1 of >99% ee . We also describe the asymmetric sulfoxidation of sulfide 5 in excellent enantiomeric excess and high chemical yield by the use of the Davis reagent.