Rhodium‐Catalyzed Enantioselective Synthesis, Structures, and Properties of Single and Double Azahelicene‐Like Molecules. Issue 36 (21st May 2021)

• Record Type: Journal Article
• Authors: Hanada, Kyoichi; Nogami, Juntaro; Miyamoto, Kazunori; Hayase, Norihiko; Nagashima, Yuki; Tanaka, Yusuke; Muranaka, Atsuya; Uchiyama, Masanobu; Tanaka, Ken
• Is Part Of: Chemistry. Volume 27:Issue 36(2021)
• Page Start: 9313
• Page End: 9319
• Publication Date: 2021-05-21
• Subjects: asymmetric catalysis -- azahelicene-like molecules -- cyanodiynes -- [2+2+2] cycloaddition -- circularly polarized luminescence; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.202005479
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: The enantioselective synthesis of aza[6] and [7]helicene‐like molecules have been achieved by the cationic rhodium(I)/axially chiral biaryl bisphosphine complex‐catalyzed intramolecular [2+2+2] cycloaddition of cyanodiynes. This protocol was successfully applied to the diastereo‐ and enantioselective synthesis of an S‐shaped double aza[6]helicene‐like molecule with a high ee value of 89 %. Although no epimerization and racemization were observed in the double carbo[6]helicene‐like molecule at 80 °C, epimerization and racemization of the double aza[6]helicene‐like molecule proceeded at 80 °C. This double aza[6]helicene‐like molecule showed good fluorescent quantum yields and chiroptical responses under both neutral and acidic conditions. Abstract : The diastereo‐ and enantioselective synthesis of a configurationally stable S‐shaped double azahelicene‐like molecule showing good chiroptical responses has been achieved with the high ee value of 89 % by the rhodium(I)/xyl‐segphos‐complex‐catalyzed double [2+2+2] cycloaddition of a dicyanotetrayne.