1361143-27-2Relevant academic research and scientific papers
C-5′-substituted cinchona alkaloid derivatives catalyse the first highly enantioselective dynamic kinetic resolutions of azlactones by thiolysis
Palacio, Carole,Connon, Stephen J.
, p. 5398 - 5413 (2013)
The highly enantioselective dynamic kinetic resolution (DKR) of azlactones by thiolysis has been achieved for the first time. Although both the parent alkaloid quinine and known C-5′-urea derivatives fail to promote the reaction effectively, a new class of C-5′-hydroxylated catalysts proved capable of catalysing the DKR of a range of azlactones derived from both unbranched- and, previously challenging, branched-chain amino acids in 84-92 % ee, including an example of the synthesis of an enantioenriched N-protected thioester derived from an extraterrestrial amino acid isolated from the Murchison meteorite. The highly enantioselective dynamic kinetic resolution (DKR) of azlactones by thiolysis has been achieved for the first time. Although both the parent alkaloid quinine and known C-5′-urea derivatives fail to promote the reaction effectively, a new class of C-5′-hydroxylated catalysts proved capable of catalysing the DKR of a range of azlactones in 84-92 % ee. Copyright
The dynamic kinetic resolution of azlactones with thiol nucleophiles catalyzed by arylated, deoxygenated cinchona alkaloids
Rodriguez-Docampo, Zaida,Quigley, Cormac,Tallon, Sean,Connon, Stephen J.
experimental part, p. 2407 - 2414 (2012/05/05)
A significant improvement of the available organocatalytic methods (in terms of product substrate scope and product enantiomeric excess) for the generation of enantioenriched α-amino acid thioesters via the dynamic kinetic resolution of azlactones is reported. C-9 arylated cinchona alkaloid catalysts have been found to be considerably superior to other bifunctional alkaloid catalysts as the promoters of this asymmetric process.
