The enantioselective synthesis of chiral [7]-helical dispirodihydro[2,1-c]indenofluorenes (DSF-IFs) was achieved for the first time in good yields with high er values (er up to 99 : 1). The crucial step of the whole reaction sequence was the enantioselective intramolecular [2+2+2] cycloaddition of tethered triynediols to indenofluorenediols, which was catalyzed by a Rh/SEGPHOS® complex. Further transformations led to the corresponding DSF-IFs. The prepared helically chiral DSF-IFs combine circularly polarized luminescence (CPL) activity (g =∼10 ) with exceptionally high fluorescence quantum yields (up to Φ =0.97).
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/chem.202100759 | DOI Listing |
Org Lett
January 2025
Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States.
The utilization of β-fluoroamines as pharmaceutical components for drug development has attracted a considerable amount of interest. However, direct access to tertiary β-fluoroamines is challenging. We herein report the rhodium-catalyzed asymmetric amination of tertiary allylic trichloroacetimidates with anilines and cyclic aliphatic amines to access tertiary β-fluoroamines, where the α-carbon atom is bonded to four different substituents, in good yield with high levels of enantioselectivity.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China.
Regiodivergent asymmetric synthesis represents a transformative strategy for the efficient generation of structurally diverse chiral products from a single set of starting materials, significantly enriching their enantiomeric composition. However, the design of radical-mediated regiodivergent and enantioselective reactions that can accommodate a wide range of functional groups and substrates has posed significant challenges. The obstacles primarily lie in switching the regioselectivity and achieving high enantiodiscrimination, especially when dealing with high-energy intermediates.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
RIKEN, Organometallic Chemistry Laboratory, 2-1 Hirosawa, 351-0198, Wako, Saitama, JAPAN.
The enantioselective [3+2] annulation of readily accessible aldimines with alkynes via C-H activation is, in principle, a straightforward and atom-efficient route for synthesizing chiral 1-aminoindenes, which are important components in a wide array of natural products, bioactive molecules, and functional materials. However, such asymmetric transformation has remained undeveloped to date due to the lack of suitable chiral catalysts. Here, we report for the first time the enantioselective [3+2] annulation of aldimines with alkynes via C-H activation using chiral half-sandwich scandium catalysts.
View Article and Find Full Text PDFJ Org Chem
December 2024
State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy and Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Tianjin 300350, China.
Here, we demonstrated a copper(II)-catalyzed enantioselective addition of aryl amines to isatin-derived -Boc-ketimines using chiral O-N-N tridentate ligands derived from BINOL and proline. Generally, the chiral acyclic ,'-ketals were obtained in high yields (up to 98%) and excellent ee values (up to 98%). Various aryl amines could be tolerated and a gram-scale reaction was also possible.
View Article and Find Full Text PDFNat Commun
December 2024
School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China.
The strain-release-driven reactions of bicyclo[1.1.0]butanes (BCBs) have received significant attention from chemists.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!