Synthesis 2012; 44(10): 1481-1484
DOI: 10.1055/s-0031-1289762
special topic
© Georg Thieme Verlag Stuttgart · New York

Multigram Synthesis of a Chiral Substituted Indoline Via Copper-Catalyzed Alkene Aminooxygenation

Fatima C. Sequeira
Department of Chemistry, The State University of New York at Buffalo, Buffalo, NY, 14260, USA, Fax: +1(716)6456963   Email: schemler@buffalo.edu
,
Michael T. Bovino
Department of Chemistry, The State University of New York at Buffalo, Buffalo, NY, 14260, USA, Fax: +1(716)6456963   Email: schemler@buffalo.edu
,
Anthony J. Chipre
Department of Chemistry, The State University of New York at Buffalo, Buffalo, NY, 14260, USA, Fax: +1(716)6456963   Email: schemler@buffalo.edu
,
Sherry R. Chemler*
Department of Chemistry, The State University of New York at Buffalo, Buffalo, NY, 14260, USA, Fax: +1(716)6456963   Email: schemler@buffalo.edu
› Author Affiliations
Further Information

Publication History

Received: 19 April 2012

Accepted: 22 April 2012

Publication Date:
27 April 2012 (eFirst)

Abstract

(S)-5-Fluoro-2-(2,2,6,6-tetramethylpiperidin-1-yloxymethyl)-1-tosylindoline, a 2-methyleneoxy-substituted chiral indoline, was synthesized on multigram scale using an efficient copper-catalyzed enantioselective intramolecular alkene aminooxygenation. The synthesis is accomplished in four steps and the indoline is obtained in 89% ee (>98% after one recrystallization). Other highlights include efficient gram-scale synthesis of the (4R,5S)-di-Ph-box ligand and efficient separation of a monoallylaniline from its N,N-diallylaniline by-product by distillation under reduced pressure.

Supporting Information

 
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