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The 9H-9-Borafluorene Dianion: A Surrogate for Elusive Diarylboryl Anion Nucleophiles.

ABSTRACT: Double reduction of the THF adduct of 9H-9-borafluorene (1?THF) with excess alkali metal affords the dianion salts M2 [1] in essentially quantitative yields (M=Li-K). Even though the added charge is stabilized through ??delocalization, [1]2- acts as a formal boron nucleophile toward organoboron (1?THF) and tetrel halide electrophiles (MeCl, Et3 SiCl, Me3 SnCl) to form B-B/C/Si/Sn bonds. The substrate dependence of open-shell versus closed-shell pathways has been investigated.

SUBMITTER: Gilmer J

PROVIDER: S-EPMC7155136 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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The 9H-9-Borafluorene Dianion: A Surrogate for Elusive Diarylboryl Anion Nucleophiles.

Gilmer Jannik J Budy Hendrik H Kaese Thomas T Bolte Michael M Lerner Hans-Wolfram HW Wagner Matthias M

Angewandte Chemie (International ed. in English) 20200122 14

Double reduction of the THF adduct of 9H-9-borafluorene (1⋅THF) with excess alkali metal affords the dianion salts M2 [1] in essentially quantitative yields (M=Li-K). Even though the added charge is stabilized through π delocalization, [1]2- acts as a formal boron nucleophile toward organoboron (1⋅THF) and tetrel halide electrophiles (MeCl, Et3 SiCl, Me3 SnCl) to form B-B/C/Si/Sn bonds. The substrate dependence of open-shell versus closed-shell pathway ...[more]

PMID: 31834978

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