Catalytic Enantioselective Synthesis of γ-Lactams with β-Quaternary Centers via Merging of C-C Activation and Sulfonyl Radical Migration was written by Yu, Xuan;Zhang, Zining;Dong, Guangbin. And the article was included in Journal of the American Chemical Society in 2022.Application of 133545-16-1 This article mentions the following:
To expand the repertoire of C-C activation, here the discovery of a Rh-catalyzed enantioselective C-C activation involving migration of a sulfonyl radical were described. This reaction directly transforms cyclobutanones containing a sulfonamide-tethered 1,3-diene moiety into γ-lactams containing a β-quaternary center with excellent enantioselectivity. This unusual process involved cleavage of C-C and N-S bonds and subsequent formation of C-N and C-S bonds. The reaction also exhibited broad functional group tolerance and a good substrate scope. A combined exptl. and computational mechanistic study suggested that the reaction goes through a Rh(I)-mediated oxidative addition into the cyclobutanone C-C bond followed by a Rh(III)-triggered N-S bond homolysis and sulfonyl radical migration. In the experiment, the researchers used many compounds, for example, (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1Application of 133545-16-1).
(R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1) belongs to chiral phosphine ligands. Generally, the efficiency of nucleophilic phosphine catalysis often depends on the nature of the tertiary phosphine. Trivalent phosphorus compounds called phosphines have a tetrahedral electron-group geometry which makes them structurally analogous to amines.Application of 133545-16-1
Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis