Asymmetric IrI-Catalysed Allylic Alkylation Of Monosubstituted Allylic Acetates With Phosphorus Amidites As Ligands

✍ Scribed by Björn Bartels; Cristina García-Yebra; Günter Helmchen

• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 150 KB
• Volume: 2003
• Category: Article
• ISSN: 1434-193X
• DOI: 10.1002/ejoc.200390162

✦ Synopsis

Abstract

Monodentate phosphorus amidites derived from 2,2′‐binaphthol and a variety of chiral amines were employed as ligands in Ir^I^‐catalysed allylic alkylations of unsymmetrically substituted allylic acetates. The enantio‐ and regioselectivities of these reactions were investigated. Phosphorus amidites of bulky secondary chiral amines induced enantioselectivities of up to 94% ee in reactions of linear substrates. Phosphorus amidites derived from chiral primary amines, which have not been previously employed in asymmetric catalysis, furnished improved regioselectivities. The use of LiCl as additive led to improved regio‐ and enantioselectivities. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)