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Radical Functionalization of Unsaturated Amino Acids: Synthesis of Side-Chain-Fluorinated, Azido-Substituted, and Hydroxylated Amino Acids.

ABSTRACT: A range of enantiomerically pure protected side-chain-fluorinated amino acids has been prepared (13 examples) by treatment of protected amino acids containing unsaturated side chains with a combination of Fe(III)/NaBH₄ and Selectfluor. The modification of the conditions by replacement of Selectfluor with NaN₃ allowed the preparation of side-chain azido-substituted amino acids (five examples), which upon catalytic hydrogenation gave the corresponding amines, isolated as lactams (four examples). Radical hydration of the unsaturated side chains leading to side-chain-hydroxylated protected amino acids has also been demonstrated.

SUBMITTER: Reeve PAP

PROVIDER: S-EPMC6648964 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Radical Functionalization of Unsaturated Amino Acids: Synthesis of Side-Chain-Fluorinated, Azido-Substituted, and Hydroxylated Amino Acids.

Reeve Philip A P PAP Grabowska Urszula U Oden Lourdes Salvador LS Wiktelius Daniel D Wångsell Fredrik F Jackson Richard F W RFW

ACS omega 20190621 6

A range of enantiomerically pure protected side-chain-fluorinated amino acids has been prepared (13 examples) by treatment of protected amino acids containing unsaturated side chains with a combination of Fe(III)/NaBH4 and Selectfluor. The modification of the conditions by replacement of Selectfluor with NaN3 allowed the preparation of side-chain azido-substituted amino acids (five examples), which upon catalytic hydrogenation gave the corresponding amines, isolated as lact ...[more]

PMID: 31460183

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