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To "Rollover" or Not? Stereoelectronically Guided C-H Functionalization Pathways from Rhodium-Abnormal NHC Intermediates.

ABSTRACT: Rollover C-H activation with transition-metal complexes has been found to be a difficult but viable pathway to functionalize potentially chelating molecules, which are otherwise reluctant to react further. However, selective rollover or nonrollover C-H activation pathway depends on the stereoelectronic demand of the associated organometallic intermediate(s). The presented work addresses the above issue on abnormal N-heterocyclic carbene (NHC) platform. Catalytic reactions of pyridine-imidazolium substrates with internal alkynes have been selectively guided toward either rollover or nonrollover C-H functionalization route via fulfilling the steric and electronic demands of the relevant rhodium(III)-abnormal NHC metallacyclic intermediates.

SUBMITTER: Dutta C

PROVIDER: S-EPMC6641269 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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To "Rollover" or Not? Stereoelectronically Guided C-H Functionalization Pathways from Rhodium-Abnormal NHC Intermediates.

Dutta Champak C Ghorai Debasish D Choudhury Joyanta J

ACS omega 20180207 2

Rollover C-H activation with transition-metal complexes has been found to be a difficult but viable pathway to functionalize potentially chelating molecules, which are otherwise reluctant to react further. However, selective rollover or nonrollover C-H activation pathway depends on the stereoelectronic demand of the associated organometallic intermediate(s). The presented work addresses the above issue on abnormal N-heterocyclic carbene (NHC) platform. Catalytic reactions of pyridine-imidazolium ...[more]

PMID: 31458483

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