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Tandem Alkylation-Second-Order Asymmetric Transformation Protocol for the Preparation of Phenylalanine-Type Tailor-Made ?-Amino Acids.

ABSTRACT: In this work, we disclose an advanced general process for the synthesis of tailor-made ?-amino acids (?-AAs) via tandem alkylation-second-order asymmetric transformation. The first step is the alkylation of the chiral Ni(II) complex of glycine Schiff base, which is conducted under mild phase-transfer conditions allowing the structural construction of target ?-AAs. The second step is based on the methodologically rare second-order asymmetric transformation, resulting in nearly complete precipitation of the corresponding (SC,RN,RC)-configured diastereomer, which can be collected by a simple filtration. The operational convenience and potential scalability of all experimental procedures, coupled with excellent stereochemical outcome, render this method of high synthetic value for the preparation of various tailor-made ?-AAs.

SUBMITTER: Takeda R

PROVIDER: S-EPMC6644829 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Tandem Alkylation-Second-Order Asymmetric Transformation Protocol for the Preparation of Phenylalanine-Type Tailor-Made α-Amino Acids.

Takeda Ryosuke R Kawashima Aki A Yamamoto Junya J Sato Tatsunori T Moriwaki Hiroki H Izawa Kunisuke K Abe Hidenori H Soloshonok Vadim A VA

ACS omega 20180822 8

In this work, we disclose an advanced general process for the synthesis of tailor-made α-amino acids (α-AAs) via tandem alkylation-second-order asymmetric transformation. The first step is the alkylation of the chiral Ni(II) complex of glycine Schiff base, which is conducted under mild phase-transfer conditions allowing the structural construction of target α-AAs. The second step is based on the methodologically rare second-order asymmetric transformation, resulting in nearly complete precipitat ...[more]

PMID: 31459102

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