Torigoe T.
Ohmura T.
*
Suginome M.
* Kyoto University, Japan
Asymmetric Cycloisomerization of
o-Alkenyl-
N-Methylanilines to Indolines by Iridium-Catalyzed C(sp
3)–H Addition to Carbon–Carbon Double Bonds.
Angew. Chem. Int. Ed. 2017;
56: 14272-14276
Key words
iridium catalysis - indolines - C–H functionalization
Significance
Isomerizations with high atom-economy are attractive strategies to generate complex
frameworks from simpler starting materials. The authors use an enantioselective iridium-catalyzed
cycloisomerization to obtain chiral indolines in good yields and excellent enantioselectivities.
Mechanistic studies suggest that C–H bond oxidative addition was the rate-determining
step.
Comment
The reaction was successful with a variety of aryl substituents on the aniline or
pendant aryl ring including heteroaromatic aryl groups. The reaction scope was also
broad, with various substituents on the nitrogen including removable benzyl groups.
The reaction proceeded through a C–H oxidative addition followed by an enantioselective
carboiridation and a reductive elimination.
