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Heteroarene Phosphinylalkylation via a Catalytic, Polarity-Reversing Radical Cascade.

ABSTRACT: A polarity-reversing radical cascade strategy for alkene di-functionalization by vicinal C-C and C-P bond-formation has been developed. This approach to concurrently adding phosphorous and a heteroarene across an olefin is enabled by photocatalytic generation of electrophilic P-centered radicals. Upon chemoselective addition to an olefin, the resulting nucleophilic C-centered radical selectively combines with electrophilic heteroarenes, such as pyridines. This multi-component coupling scheme for phosphinylalkylation complements classic two-component methods for hydrophosphinylation of alkenes and C-H phosphinylation of arenes. Included competition and photo-quenching experiments provide insight into the selectivity and mechanism of this polarity-reversal pathway.

SUBMITTER: Buquoi JQ

PROVIDER: S-EPMC6608589 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Heteroarene Phosphinylalkylation via a Catalytic, Polarity-Reversing Radical Cascade.

Buquoi J Quentin JQ Lear Jeremy M JM Gu Xin X Nagib David A DA

ACS catalysis 20190506 6

A polarity-reversing radical cascade strategy for alkene di-functionalization by vicinal C-C and C-P bond-formation has been developed. This approach to concurrently adding phosphorous and a heteroarene across an olefin is enabled by photocatalytic generation of electrophilic P-centered radicals. Upon chemoselective addition to an olefin, the resulting nucleophilic C-centered radical selectively combines with electrophilic heteroarenes, such as pyridines. This multi-component coupling scheme for ...[more]

PMID: 31275730

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