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Asymmetric Synthesis of Tertiary ? -Hydroxyketones by Enantioselective Decarboxylative Chlorination and Subsequent Nucleophilic Substitution.

ABSTRACT: Chiral tertiary ?-hydroxyketones were synthesized with high enantiopurity by asymmetric decarboxylative chlorination and subsequent nucleophilic substitution. We recently reported the asymmetric decarboxylative chlorination of ?-ketocarboxylic acids in the presence of a chiral primary amine catalyst to obtain ?-chloroketones with high enantiopurity. Here, we found that nucleophilic substitution of the resulting ?-chloroketones with tetrabutylammonium hydroxide yielded the corresponding ?-hydroxyketones without loss of enantiopurity. The reaction proceeded smoothly even at a tertiary carbon. The proposed method would be useful for the preparation of chiral tertiary alcohols.

SUBMITTER: Kam MK

PROVIDER: S-EPMC7503659 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Asymmetric Synthesis of Tertiary α -Hydroxyketones by Enantioselective Decarboxylative Chlorination and Subsequent Nucleophilic Substitution.

Kam Mei Kee MK Sugiyama Akira A Kawanishi Ryouta R Shibatomi Kazutaka K

Molecules (Basel, Switzerland) 20200827 17

Chiral tertiary α-hydroxyketones were synthesized with high enantiopurity by asymmetric decarboxylative chlorination and subsequent nucleophilic substitution. We recently reported the asymmetric decarboxylative chlorination of β-ketocarboxylic acids in the presence of a chiral primary amine catalyst to obtain α-chloroketones with high enantiopurity. Here, we found that nucleophilic substitution of the resulting α-chloroketones with tetrabutylammonium hydroxide yielded the corresponding α-hydroxy ...[more]

PMID: 32867091

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