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Visible light amination/Smiles cascade: access to phthalazine derivatives.

ABSTRACT: We report the synthesis of various phthalazines via a new cascade reaction, initiated by visible light photocatalysis, involving a radical hydroamination reaction followed by a radical Smiles rearrangement. Phthalazine derivatives are obtained in high yields and from a broad scope readily accessible ortho-alkynylsulfonohydrazone precursors. The mild photoredox conditions ensure an excellent functional group tolerance. Application of this strategy to a one-pot protocol starting from the corresponding carbonyl compounds, and subsequent functionalization allow the rapid synthesis of structurally diverse structures.

SUBMITTER: Brachet E

PROVIDER: S-EPMC6018559 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Visible light amination/Smiles cascade: access to phthalazine derivatives.

Brachet Etienne E Marzo Leyre L Selkti Mohamed M König Burkhard B Belmont Philippe P

Chemical science 20160506 8

We report the synthesis of various phthalazines via a new cascade reaction, initiated by visible light photocatalysis, involving a radical hydroamination reaction followed by a radical Smiles rearrangement. Phthalazine derivatives are obtained in high yields and from a broad scope readily accessible ortho-alkynylsulfonohydrazone precursors. The mild photoredox conditions ensure an excellent functional group tolerance. Application of this strategy to a one-pot protocol starting from ...[more]

PMID: 30155150

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