Dirhodium(II) tetrakis[N-tetrafluorophthaloyl-(S)-tert-leucinate]: an exceptionally effective Rh(II) catalyst for enantiotopically selective aromatic C–H insertions of diazo ketoesters

✍ Scribed by Hideyuki Tsutsui; Yukiko Yamaguchi; Shinji Kitagaki; Seiichi Nakamura; Masahiro Anada; Shunichi Hashimoto

• Book ID: 104359686
• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 200 KB
• Volume: 14
• Category: Article
• ISSN: 0957-4166
• DOI: 10.1016/s0957-4166(03)00075-2

✦ Synopsis

Dirhodium(II) tetrakis[N-tetrafluorophthaloyl-(S)-tert-leucinate], Rh 2 [(S)-TFPTTL] 4 , in which the phthalimido hydrogen atoms of the parent dirhodium(II) complex are substituted by fluorine atoms, dramatically enhances the reactivity and enantioselectivity (up to 97% ee) in intramolecular aromatic C-H insertion reactions of methyl 4-alkyl-2-diazo-4,4-diphenyl-3-oxopropionates. Catalysis with the use of 0.001 mol% of Rh 2 [(S)-TFPTTL] 4 has achieved the highest turnover number (up to 98,000 with the methyl substituent) ever recorded for chiral dirhodium(II) complex-catalyzed carbene transformations, without compromising the yield or enantioselectivity of the process.