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NHC Catalysis for Umpolung Pyridinium Alkylation via Deoxy-Breslow Intermediates.

ABSTRACT: Umpolung N-heterocyclic carbene (NHC) catalysis of non-aldehyde substrates offers new pathways for C-C bond formation, but has proven challenging to develop in terms of viable substrate classes. Here, we demonstrate that pyridinium ions can undergo NHC addition and subsequent intramolecular C-C bond formation through a deoxy-Breslow intermediate. The alkylation demonstrates, for the first time, that deoxy-Breslow intermediates are viable for catalytic umpolung of areniums.

SUBMITTER: Wu T

PROVIDER: S-EPMC9306516 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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NHC Catalysis for Umpolung Pyridinium Alkylation via Deoxy-Breslow Intermediates.

Wu Terence T Tatton Matthew R MR Greaney Michael F MF

Angewandte Chemie (International ed. in English) 20220218 15

Umpolung N-heterocyclic carbene (NHC) catalysis of non-aldehyde substrates offers new pathways for C-C bond formation, but has proven challenging to develop in terms of viable substrate classes. Here, we demonstrate that pyridinium ions can undergo NHC addition and subsequent intramolecular C-C bond formation through a deoxy-Breslow intermediate. The alkylation demonstrates, for the first time, that deoxy-Breslow intermediates are viable for catalytic umpolung of areniums. ...[more]

PMID: 35103381

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