Regio‐ and Enantioselective Synthesis of N‐Substituted Pyrazoles by Rhodium‐Catalyzed Asymmetric Addition to Allenes |
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Authors: | Alexander M. Haydl Dr. Kun Xu Prof. Dr. Bernhard Breit |
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Affiliation: | Institut für Organische Chemie, Albert‐Ludwigs‐Universit?t Freiburg, Albertstrasse 21, 79104 Freiburg im Breisgau (Germany) |
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Abstract: | The rhodium‐catalyzed asymmetric N‐selective coupling of pyrazole derivatives with terminal allenes gives access to enantioenriched secondary and tertiary allylic pyrazoles, which can be employed for the synthesis of medicinally important targets. The reaction tolerates a large variety of functional groups and labelling experiments gave insights into the reaction mechanism. This new methodology was further applied in a highly efficient synthesis of JAK 1/2 inhibitor (R)‐ruxolitinib. |
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Keywords: | allenes allylic compounds asymmetric catalysis heterocycles rhodium |
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