New Synthesis of Fischer Indole Hydrazone Intermediates

V. Khedkar; A. Tillack; M. Michalik; M. Beller

doi:10.1055/s-2005-921587

RSS-Feed abonnieren

Bitte kopieren Sie die angezeigte URL und fügen sie dann in Ihren RSS-Reader ein.

https://www.thieme-connect.de/rss/thieme/de/10.1055-s-00000131.xml

Teilen / Bookmarken

Facebook X Linkedin Weibo

PDF herunterladen

Synfacts 2005(3): 0287-0287
DOI: 10.1055/s-2005-921587

Synthesis of Heterocycles

New Synthesis of Fischer Indole Hydrazone Intermediates

Contributor(s): Victor Snieckus, Till Vogel
V. Khedkar, A. Tillack, M. Michalik, M. Beller*
Leibnitz-Institut für Organische Katalyse an der Universität Rostock e.V., Germany

Weitere Informationen

Publikationsverlauf

Publikationsdatum:
22. November 2005 (online)

Lizenzen und Reprints

Significance

A one-pot domino reaction sequence for the synthesis of tryptophols (3-hydroxyethylindole) and its homologues is reported. The key step is a titanium-catalyzed hydroamination of alkynes by aryl hydrazines to give azatitanacycles with excellent Markovnikov regioselectivity. Following rearrangement and removal of titanium, hydrazones are produced which, when subjected to Lewis acid-mediated Fischer indole cyclization, give substituted tryptophols in up to 95% yield.