Enantioselective Synthesis of 1- and 4-Hydroxytetrahydrocarbazoles through Asymmetric Transfer Hydrogenation

DİLEK Ö., Patir S., Ertürk E.

Synlett, vol.30, no.1, pp.69-72, 2019 (SCI-Expanded, Scopus) identifier

  • Publication Type: Article / Article
  • Volume: 30 Issue: 1
  • Publication Date: 2019
  • Doi Number: 10.1055/s-0037-1610351
  • Journal Name: Synlett
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.69-72
  • Keywords: asymmetric synthesis, hexahydrofurocarbazolone, hydroxytetrahydrocarbazoles, ruthenium catalysis, tetrahydrocarbazolones, transfer hydrogenation
  • Isparta University of Applied Sciences Affiliated: Yes

Abstract

Several 1- and 4-hydroxytetrahydrocarbazoles were prepared in high yields (up to 99%) and excellent enantiomeric excesses (up to >99% ee) from the corresponding 1- and 4-oxotetrahydrocarbazoles through asymmetric transfer hydrogenation by using the commercially available Noyori-Ikariya ruthenium catalyst. The immediate use of the freshly prepared catalyst and the use of a HCO 2 H-DABCO (11:6) mixture as the hydrogen source are crucial for achieving high activity and enantioselectivity. In this way, a tetrahydrocarbazole heterocycle fused to a lactone moiety was synthesized in 45% yield and 97% ee.