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Catalytic asymmetric synthesis of quaternary trifluoromethyl α- to ε-amino acid derivatives via umpolung allylation/2-aza-Cope rearrangement.

ABSTRACT: In this study, we developed an efficient Ir-catalyzed cascade umpolung allylation/2-aza-Cope rearrangement of tertiary α-trifluoromethyl α-amino acid derivatives for the preparation of a variety of quaternary α-trifluoromethyl α-amino acids in high yields with excellent enantioselectivities. The umpolung reactivity empowered by the activation of the key isatin-ketoimine moiety obviates the intractable enantioselectivity control in Pd-catalyzed asymmetric linear α-allylation. In combination with quasi parallel kinetic resolution or kinetic resolution, the generality of this method is further demonstrated by the first preparation of enantioenriched quaternary trifluoromethyl β-, γ-, δ- and ε-amino acid derivatives.

SUBMITTER: Sun XS

PROVIDER: S-EPMC8162408 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Catalytic asymmetric synthesis of quaternary trifluoromethyl α- to ε-amino acid derivatives <i>via</i> umpolung allylation/2-aza-Cope rearrangement.

Sun Xi-Shang XS Wang Xing-Heng XH Tao Hai-Yan HY Wei Liang L Wang Chun-Jiang CJ

Chemical science 20200917 40

In this study, we developed an efficient Ir-catalyzed cascade umpolung allylation/2-aza-Cope rearrangement of tertiary α-trifluoromethyl α-amino acid derivatives for the preparation of a variety of quaternary α-trifluoromethyl α-amino acids in high yields with excellent enantioselectivities. The umpolung reactivity empowered by the activation of the key isatin-ketoimine moiety obviates the intractable enantioselectivity control in Pd-catalyzed asymmetric linear α-allylation. In combination with ...[more]

PMID: 34094346

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