Enantioselective Synthesis of 1- and 4-Hydroxytetrahydrocarbazoles through Asymmetric Transfer Hydrogenation
Synlett, vol.30, no.1, pp.69-72, 2019 (SCI-Expanded, Scopus)
- 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.