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Photocatalytic ?-Tertiary Amine Synthesis via C-H Alkylation of Unmasked Primary Amines.

ABSTRACT: A practical, catalytic entry to ?,?,?-trisubstituted (?-tertiary) primary amines by C-H functionalisation has long been recognised as a critical gap in the synthetic toolbox. We report a simple and scalable solution to this problem that does not require any in situ protection of the amino group and proceeds with 100?% atom-economy. Our strategy, which uses an organic photocatalyst in combination with azide ion as a hydrogen atom transfer (HAT) catalyst, provides a direct synthesis of ?-tertiary amines, or their corresponding ?-lactams. We anticipate that this methodology will inspire new retrosynthetic disconnections for substituted amine derivatives in organic synthesis, and particularly for challenging ?-tertiary primary amines.

SUBMITTER: Ryder ASH

PROVIDER: S-EPMC7496683 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Photocatalytic α-Tertiary Amine Synthesis via C-H Alkylation of Unmasked Primary Amines.

Ryder Alison S H ASH Cunningham William B WB Ballantyne George G Mules Tom T Kinsella Anna G AG Turner-Dore Jacob J Alder Catherine M CM Edwards Lee J LJ McKay Blandine S J BSJ Grayson Matthew N MN Cresswell Alexander J AJ

Angewandte Chemie (International ed. in English) 20200611 35

A practical, catalytic entry to α,α,α-trisubstituted (α-tertiary) primary amines by C-H functionalisation has long been recognised as a critical gap in the synthetic toolbox. We report a simple and scalable solution to this problem that does not require any in situ protection of the amino group and proceeds with 100 % atom-economy. Our strategy, which uses an organic photocatalyst in combination with azide ion as a hydrogen atom transfer (HAT) catalyst, provides a direct synthesis of α-tertiary ...[more]

PMID: 32391968

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