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Coetaneous catalytic kinetic resolution of alkynes and azides through asymmetric triazole formation.

ABSTRACT: A non-enzymatic simultaneous (coined coetaneous) kinetic resolution of a racemic alkyne and racemic azide, utilising an asymmetric CuAAC reaction is reported. The use of a CuCl (R,R)-Ph-Pybox catalyst system effects a simultaneous kinetic resolution of two racemic starting materials to give one major triazolic diastereoisomer in the ratio 74:12:4:10 (dr 84:16, 90% ee maj). The corresponding control reaction using an achiral copper catalyst gives the four possible diastereoisomers in a 23:27:23:27 ratio, demonstrating minimal inherent substrate control.

SUBMITTER: Brittain WDG

PROVIDER: S-EPMC6803658 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Coetaneous catalytic kinetic resolution of alkynes and azides through asymmetric triazole formation.

Brittain William D G WDG Dalling Andrew G AG Sun Zhenquan Z Duff Cécile S Le CSL Male Louise L Buckley Benjamin R BR Fossey John S JS

Scientific reports 20191021 1

A non-enzymatic simultaneous (coined coetaneous) kinetic resolution of a racemic alkyne and racemic azide, utilising an asymmetric CuAAC reaction is reported. The use of a CuCl (R,R)-Ph-Pybox catalyst system effects a simultaneous kinetic resolution of two racemic starting materials to give one major triazolic diastereoisomer in the ratio 74:12:4:10 (dr 84:16, 90% ee maj). The corresponding control reaction using an achiral copper catalyst gives the four possible diastereoisomers in a 23:27:23:2 ...[more]

PMID: 31636274

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