1239744-52-5Relevant academic research and scientific papers
Site- and Enantioselective Iridium-Catalyzed Desymmetric Mono-Hydrogenation of 1,4-Dienes
Ahlquist, M?rten S. G.,Andersson, Pher G.,Nolan, Mark D.,Peters, Bram B. C.,Schulze, Erik J.,Singh, Thishana,Su, Hao,Wu, Haibo,Yang, Jianping
supporting information, p. 19428 - 19434 (2021/07/26)
The control of site selectivity in asymmetric mono-hydrogenation of dienes or polyenes remains largely underdeveloped. Herein, we present a highly efficient desymmetrization of 1,4-dienes via iridium-catalyzed site- and enantioselective hydrogenation. This methodology demonstrates the first iridium-catalyzed hydrogenative desymmetriation of meso dienes and provides a concise approach to the installation of two vicinal stereogenic centers adjacent to an alkene. High isolated yields (up to 96 %) and excellent diastereo- and enantioselectivities (up to 99:1 d.r. and 99 % ee) were obtained for a series of divinyl carbinol and divinyl carbinamide substrates. DFT calculations reveal that an interaction between the hydroxy oxygen and the reacting hydride is responsible for the stereoselectivity of the desymmetrization of the divinyl carbinol. Based on the calculated energy profiles, a model that simulates product distribution over time was applied to show an intuitive kinetics of this process. The usefulness of the methodology was demonstrated by the synthesis of the key intermediates of natural products zaragozic acid A and (+)-invictolide.
Catalytic enantioselective synthesis of sterically demanding alcohols using di(2°-alkyl)zinc prepared by the refined Charette's method
Hatano, Manabu,Mizuno, Tomokazu,Ishihara, Kazuaki
supporting information; experimental part, p. 5443 - 5445 (2010/10/04)
A highly practical, catalytic enantioselective 2°-alkyl addition to aldehydes and ketones was developed. Chiral phosphoramide ligand (1) with salt-free and solvent-free di(2°-alkyl)zinc reagents prepared from (2°-alkyl)MgCl was essential. The Royal Society of Chemistry 2010.
