Rhodium-Catalyzed Highly Diastereo- and Enantioselective Synthesis of a Configurationally Stable S-Shaped Double Helicene-Like Molecule was written by Kinoshita, Suzuka;Yamano, Ryota;Shibata, Yu;Tanaka, Yusuke;Hanada, Kyoichi;Matsumoto, Takashi;Miyamoto, Kazunori;Muranaka, Atsuya;Uchiyama, Masanobu;Tanaka, Ken. And the article was included in Angewandte Chemie, International Edition in 2020.Recommanded Product: (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) This article mentions the following:
An S-shaped double helicene-like mol. (>99% ee), possessing stable helical chirality, has been synthesized by the rhodium(I)/difluorphos complex-catalyzed highly diastereo- and enantioselective intramol. double [2+2+2] cycloaddition of a 2-naphthol- and benzene-linked hexayne. The collision between two terminal naphthalene rings destabilizes the helical chirality of the S-shaped double helicene-like mol., but the introduction of two addnl. fused benzene rings significantly increases the configurational stability. Thus, no epimerization and racemization were observed even at 100°C. The enantiopure S-shaped double helicene-like mol. forms a trimer through the multiple C-H…π and C-H…O interactions in the solid-state. The trimers stack to form columnar packing structures, in which neighboring stacks have opposite dipole directions. The accumulation of helical structures in the same direction in the S-shaped double helicene-like mol. enhanced the chiroptical properties. In the experiment, the researchers used many compounds, for example, (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1Recommanded Product: (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine)).
(R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1) belongs to chiral phosphine ligands. The synthesis of novel trialkylphosphines can be quite difficult, thereby limiting the scope of their chiral variants. Chiral ligands coordinate to metal centers to create an asymmetric environment around the reaction centers, which eventually affects enantioselectivity and reaction rate.Recommanded Product: (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine)
Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis