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Visible Light Activation of Boronic Esters Enables Efficient Photoredox C(sp(2) )-C(sp(3) ) Cross-Couplings in Flow.

ABSTRACT: We report herein a new method for the photoredox activation of boronic esters. Using these reagents, an efficient and high-throughput continuous flow process was developed to perform a dual iridium- and nickel-catalyzed C(sp(2) )-C(sp(3) ) coupling by circumventing solubility issues associated with potassium trifluoroborate salts. Formation of an adduct with a pyridine-derived Lewis base was found to be essential for the photoredox activation of the boronic esters. Based on these results we were able to develop a further simplified visible light mediated C(sp(2) )-C(sp(3) ) coupling method using boronic esters and cyano heteroarenes under flow conditions.

SUBMITTER: Lima F

PROVIDER: S-EPMC5113707 | biostudies-other | 2016 Nov

REPOSITORIES: biostudies-other

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Visible Light Activation of Boronic Esters Enables Efficient Photoredox C(sp2 )-C(sp3 ) Cross-Couplings in Flow.

Lima Fabio F Kabeshov Mikhail A MA Tran Duc N DN Battilocchio Claudio C Sedelmeier Joerg J Sedelmeier Gottfried G Schenkel Berthold B Ley Steven V SV

Angewandte Chemie (International ed. in English) 20161006 45

We report herein a new method for the photoredox activation of boronic esters. Using these reagents, an efficient and high-throughput continuous flow process was developed to perform a dual iridium- and nickel-catalyzed C(sp2 )-C(sp3 ) coupling by circumventing solubility issues associated with potassium trifluoroborate salts. Formation of an adduct with a pyridine-derived Lewis base was found to be essential for the photoredox activation of the boronic esters. Based on the ...[more]

PMID: 27709749

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