Ligand Effects in Gold- and Platinum-Catalyzed Cyclization of Enynes: Chiral Gold Complexes for Enantioselective Alkoxycyclization
Citations Over TimeTop 1% of 2005 papers
Abstract
Phosphine and bidentate N-N ligands inhibit the Alder-ene-type cycloisomerization of enynes catalyzed by Pt(II) and favor the alkoxycyclization process. The enantioselective Pt(II)-catalyzed alkoxycyclization has been studied in the presence of chiral mono- and bidentate phosphines, as well as chiral bidentate N-N ligands. Modest levels of enantioselection (up to 50% ee) have been obtained with Tol-BINAP as ligand. The alkoxycyclizations with a catalyst formed from [Au(L)Cl]/AgX proceed more readily, and up to 94% ee's have been obtained using [(AuCl)2(Tol-BINAP)] ( 47 ) as the precatalyst. The X-ray crystal structures of Au(I) complexes 47 and chloro-(R)-2-(tert-butylsulfenyl)-1-(diphenylphosphino)ferrocene gold(I) ( 39 ) show the AuCl fragments monocoordinated with the P centers of the chiral phosphine ligands.
Related Papers
- → A relay catalysis strategy for enantioselective nickel-catalyzed migratory hydroarylation forming chiral α-aryl alkylboronates(2021)102 cited
- → Enantioselective aziridination reaction of α,β-unsaturated aldehydes using an organocatalyst and tert-butyl N-arenesulfonyloxycarbamates(2009)80 cited
- → Dynamic Ligand Exchange as a Mechanistic Probe in Pd-Catalyzed Enantioselective C–H Functionalization Reactions Using Monoprotected Amino Acid Ligands(2017)22 cited
- → Enantioselective hydrogenation of α-ketoesters: Preparation and catalytic behavior of different alumina-supported platinum catalysts modified with cinchonidine(1990)120 cited
- → Titanium‐Catalyzed Enantioselective Additions of Alkyl Groups to Aldehydes: Mechanistic Studies and New Concepts in Asymmetric Catalysis(2003)