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Transition Metal Catalyst-Free, Base-Promoted 1,2-Additions of Polyfluorophenylboronates to Aldehydes and Ketones.

ABSTRACT: A novel protocol for the transition metal-free 1,2-addition of polyfluoroaryl boronate esters to aldehydes and ketones is reported, which provides secondary alcohols, tertiary alcohols, and ketones. Control experiments and DFT calculations indicate that both the ortho-F substituents on the polyfluorophenyl boronates and the counterion K⁺ in the carbonate base are critical. The distinguishing features of this procedure include the employment of commercially available starting materials and the broad scope of the reaction with a wide variety of carbonyl compounds giving moderate to excellent yields. Intriguing structural features involving O-H⋅⋅⋅O and O-H⋅⋅⋅N hydrogen bonding, as well as arene-perfluoroarene interactions, in this series of racemic polyfluoroaryl carbinols have also been addressed.

SUBMITTER: Liu Z

PROVIDER: S-EPMC8362073 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Transition Metal Catalyst-Free, Base-Promoted 1,2-Additions of Polyfluorophenylboronates to Aldehydes and Ketones.

Liu Zhiqiang Z Kole Goutam Kumar GK Budiman Yudha P YP Tian Ya-Ming YM Friedrich Alexandra A Luo Xiaoling X Westcott Stephen A SA Radius Udo U Marder Todd B TB

Angewandte Chemie (International ed. in English) 20210617 30

A novel protocol for the transition metal-free 1,2-addition of polyfluoroaryl boronate esters to aldehydes and ketones is reported, which provides secondary alcohols, tertiary alcohols, and ketones. Control experiments and DFT calculations indicate that both the ortho-F substituents on the polyfluorophenyl boronates and the counterion K<sup>+</sup> in the carbonate base are critical. The distinguishing features of this procedure include the employment of commercially available starting materials ...[more]

PMID: 33901332

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