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Ir(iii)-catalyzed ortho C-H alkylations of (hetero)aromatic aldehydes using alkyl boron reagents.

ABSTRACT: Transition-metal-catalyzed C-H alkylation reactions directed by aldehydes or ketones have been largely restricted to electronically activated alkenes. Herein, we report a general protocol for the Ir(iii)-catalyzed ortho C-H alkylations of (hetero)aromatic aldehydes using alkyl boron reagents as the coupling partner. Featuring aniline as an inexpensive catalytic ligand, the method was compatible with a wide variety of benzaldehydes, heterocyclic aldehydes, potassium alkyltrifluoroborates as well as a few ?,?-unsaturated aldehydes. An X-ray crystal structure of a benzaldehyde ortho C-H iridation intermediate was also successfully obtained.

SUBMITTER: Chen XY

PROVIDER: S-EPMC6301268 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Ir(iii)-catalyzed ortho C-H alkylations of (hetero)aromatic aldehydes using alkyl boron reagents.

Chen Xiao-Yang XY Sorensen Erik J EJ

Chemical science 20181003 48

Transition-metal-catalyzed C-H alkylation reactions directed by aldehydes or ketones have been largely restricted to electronically activated alkenes. Herein, we report a general protocol for the Ir(iii)-catalyzed ortho C-H alkylations of (hetero)aromatic aldehydes using alkyl boron reagents as the coupling partner. Featuring aniline as an inexpensive catalytic ligand, the method was compatible with a wide variety of benzaldehydes, heterocyclic aldehydes, potassium alkyltrifluoroborates a ...[more]

PMID: 30647887

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