Synthesis of enantiopure triazolium salts from pyroglutamic acid and their evaluation in the benzoin condensation
Tetrahedron AsymmetryPublished 1 June 2008
Dieter Enders, Jianwei Han
Citations123
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Abstract
A family of enantiopure 1,2,4-triazolium salts were prepared starting from the inexpensive (S)-pyroglutamic acid. After treatment with base, the corresponding N-heterocyclic carbenes were tested as organocatalysts in the asymmetric benzoin condensation and gave good yields and up to 95% ee.
Keywords
Chemistry
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