Details

Autor(en) / Beteiligte

• Wagner, Bernd
• Hiller, Wolf
• Ohno, Hiroaki
• Krause, Norbert

Titel

Gold-catalyzed three-component spirocyclization: a one-pot approach to functionalized pyrazolidines

Ist Teil von

• Organic & biomolecular chemistry, 2016-02, Vol.14 (5), p.1579-1583

Ort / Verlag

England

Erscheinungsjahr

2016

Quelle

MEDLINE

Beschreibungen/Notizen

• An efficient, highly atom economic synthesis of hitherto unknown spirocyclic pyrazolidines in a one-pot process was developed. The gold-catalyzed three-component coupling of alkynols, hydrazines and aldehydes or ketones likely proceeds via cycloisomerization of the alkynol to an exocyclic enol ether and subsequent [3 + 2]-cycloaddition of an azomethine ylide. A library of 29 derivatives with a wide range of functional groups was synthesized in up to 97% yield. With this new method, every position in the final product can be substituted which renders the method ideal for applications in combinatorial or medicinal chemistry.