Application of 256390-47-3On May 20, 2016 ,《Direct Catalytic Asymmetric Mannich-Type Reaction of Alkylamides》 appeared in Organic Letters. The author of the article were Arteaga, Fernando Arteaga; Liu, Zijian; Brewitz, Lennart; Chen, Jianyang; Sun, Bo; Kumagai, Naoya; Shibasaki, Masakatsu. The article conveys some information:
Direct enolate formation coupled with subsequent enantioselective C-C bond formation remains a topic of intense interest in asym. catalysis. This methodol. is achieved even with low acidic amides without an electron-withdrawing group at the α-position in the context of a Mannich-type reaction. Acetate-, propionate-, and butyrate-type 7-azaindoline amides served as enolate precursors to afford the desired Mannich adducts with high stereoselectivity, e.g., anti-adducts I (R1 = Ph, 4-MeC6H4, 3-furyl, etc.), and ligand-enabled diastereo-divergency provided access to both anti/syn diastereomers. The facile transformation of the amide moiety ensures the synthetic utility of the Mannich adducts. In the experimental materials used by the author, we found (R)-(6,6′-Dimethoxybiphenyl-2,2′-diyl)bis[bis(3,4,5-trimethoxyphenyl)phosphine](cas: 256390-47-3Application of 256390-47-3)
(R)-(6,6′-Dimethoxybiphenyl-2,2′-diyl)bis[bis(3,4,5-trimethoxyphenyl)phosphine](cas: 256390-47-3) belongs to chiral phosphine ligands. Nucleophilic phosphine catalysis often involves the formation of Lewis adducts, namely phosphonium (di)enolate zwitterions, as reaction intermediates. These intermediates are formed through nucleophilic attack of the phosphine catalysts at electron-poor nuclei (normally carbon atoms) and then proceed through several steps to form new chemical bonds. Application of 256390-47-3
Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis