Kinetic Resolution of Cyclic Secondary Azides, Using an Enantioselective Copper-Catalyzed Azide-Alkyne Cycloaddition.
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ABSTRACT:
SUBMITTER: Alexander JR
PROVIDER: S-EPMC6631410 | biostudies-literature | 2019 Jun
REPOSITORIES: biostudies-literature
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Kinetic Resolution of Cyclic Secondary Azides, Using an Enantioselective Copper-Catalyzed Azide-Alkyne Cycloaddition.
Alexander Juliana R JR Ott Amy A AA Liu En-Chih EC Topczewski Joseph J JJ
Organic letters 20190522 11
An enantioselective copper-catalyzed azide-alkyne cycloaddition (E-CuAAC) is reported by kinetic resolution. Chiral triazoles were isolated in high yield with limiting alkyne (up to 97:3 enantiomeric ratio (er)). A range of substrates were tolerated (>30 examples), and the reaction was scaled to >1 g. The er of a triazole product could be enhanced by recrystallization and the recovered scalemic azide could be racemized and recycled. Recycling the azide allows efficient use of the undesired azide ...[more]
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