Enantioselective catalytic conjugate addition of dialkylzinc reagents using copper-phosphoramidite complexes; ligand variation and non-linear effects was written by Arnold, Leggy A.;Imbos, Rosalinde;Mandoli, Alessandro;De Vries, Andre H. M.;Naasz, Robert;Feringa, Ben L.. And the article was included in Tetrahedron in 2000.COA of Formula: C24H22NO2P This article mentions the following:
A variety of new chiral phosphoramidites was synthesized and tested in the copper-catalyzed enantioselective conjugate addition of Et2Zn to cyclohexenone and chalcone to assess the structural features that are important for stereocontrol. A sterically demanding amine moiety is essential to reach high e.e.’s. Enantioselectivities for chalcones up to 89% and for cyclic enones up to 98% were found. Studies on non-linear effects with the best ligands for both cyclohexenone and chalcone showed clear non-linear effects for both cyclic and acyclic enones. In the experiment, the researchers used many compounds, for example, (11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3COA of Formula: C24H22NO2P).
(11bS)-N,N-Diethyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepin-4-amine (cas: 252288-04-3) belongs to chiral phosphine ligands. The synthesis of novel trialkylphosphines can be quite difficult, thereby limiting the scope of their chiral variants. Over the last decade, however, and especially since 2005, considerable progress has been made in asymmetric phosphine catalysis.COA of Formula: C24H22NO2P
Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis