《Direct Catalytic Asymmetric Aldol Reaction of α-Alkoxyamides to α-Fluorinated Ketones》 was published in Angewandte Chemie, International Edition in 2019. These research results belong to Pluta, Roman; Kumagai, Naoya; Shibasaki, Masakatsu. Application In Synthesis of (R)-(6,6′-Dimethoxybiphenyl-2,2′-diyl)bis[bis(3,4,5-trimethoxyphenyl)phosphine] The article mentions the following:
α-Oxygen-functionalized amides found particular utility as enolate surrogates for direct aldol couplings with α-fluorinated ketones in a catalytic manner. Because of the likely involvement of open transition states, both syn- and anti-aldol adducts can be accessed with high enantioselectivity by judicious choice of the chiral ligands. A broad variety of alkoxy substituents on the amides and aryl and fluoroalkyl groups on the ketone were tolerated and the corresponding substrates delivered a range of enantioenriched fluorinated 1,2-dihydroxycarboxylic acid derivatives with divergent diastereoselectivity depending on the ligand used. The amide moiety of the aldol adduct was transformed into a variety of functional groups without protection of the tertiary alc., showcasing the synthetic utility of the present asym. aldol process. The experimental process involved the reaction of (R)-(6,6′-Dimethoxybiphenyl-2,2′-diyl)bis[bis(3,4,5-trimethoxyphenyl)phosphine](cas: 256390-47-3Application In Synthesis of (R)-(6,6′-Dimethoxybiphenyl-2,2′-diyl)bis[bis(3,4,5-trimethoxyphenyl)phosphine])
(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 In Synthesis of (R)-(6,6′-Dimethoxybiphenyl-2,2′-diyl)bis[bis(3,4,5-trimethoxyphenyl)phosphine]
Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis