Enantioselective synthesis of unsymmetrical triarylmethanes by chiral Bronsted acids was written by Sun, Feng-Lai;Zheng, Xiao-Jian;Gu, Qing;He, Qing-Li;You, Shu-Li. And the article was included in European Journal of Organic Chemistry in 2010.Safety of (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide This article mentions the following:
Chiral Bronsted acid catalyzed Friedel-Crafts alkylation of electron-rich arenes with (3-indolyl)methanamines has been realized to provide an efficient synthesis of enantioenriched unsym. triarylmethanes. With 5 mol-% of a newly developed chiral phosphoric acid, the enantioenriched unsym. triarylmethanes were obtained in excellent yields with up to 91 % ee. In the experiment, the researchers used many compounds, for example, (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide (cas: 1043567-32-3Safety of (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide).
(11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide (cas: 1043567-32-3) belongs to chiral phosphine ligands. Many phosphine-catalyzed reactions have been developed for the syntheses of various biologically important acyclic and cyclic molecules. Asymmetric variants of these reactions have evolved relatively slowly. Indeed, very little research on chiral tertiary phosphine-catalyzed asymmetric reactions occurred prior to the year 2000.Safety of (11bS)-4-Hydroxy-2,6-di(phenanthren-9-yl)dinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide
Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis