with exclusive regioselectivity and stereoselectivity. Functional application of such a resultant product by oxidative addition and epoxidation is also explored. Notably, the treatment of a pyrroline-fused N-glycoside (3a) with TMSOTf efficiently leads to an interesting unexpected C-nucleoside (9) via a TMSOTf-inducing ring opening/acetyl migration/ringclosingreaction sequence.
in a stereoselective manner. The reaction proceeds through generation of an α‐imino rhodium carbene complex, nucleophilic addition of the sulfur atom of a thioester onto the carbenoid carbonatom, and subsequent intramolecular migration of the acyl groupfrom the sulfur atom to the imino nitrogen atom. The method is successfully applied to a ring‐expansion reaction of thiolactones, thus leading to
1,3‐Difunctionalization of Imino‐Carbenes via Rhodium‐Catalyzed Reactions of Triazoles with Acyl Selenides
作者:Fang Li、Chao Pei、Calogero Quaranta、Rene M. Koenigs
DOI:10.1002/adsc.202100629
日期:2021.9.21
rhodium-catalyzed reaction of triazoles with acyl selenides. Under thermal reaction conditions and in the presence of a rhodium catalyst, a rapid 1,3-difunctionalization reaction occurs to provide valuable α-seleno enamides with high stereoselectivity and broad functional group tolerance, which was demonstrated in 35 examples with up to 95% yield. Computational calculations suggest a reaction pathway that
An enamido group is introduced site-selectively at the C(3)-position of indoles by the rhodium(II)-catalyzed reaction with N-sulfonyl-1,2,3-triazoles. Formally, an alpha-imino rhodium carbene complex is inserted into the C(3)-H bond of an indole.