Asymmetric Synthesis of Chiral 1,2-Bis(Boronic) Esters Featuring Acyclic, Non-Adjacent 1,3-Stereocenters.

Autor: Jiang XM; School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China., Ji CL; School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China., Ge JF; School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China., Zhao JH; College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai, 201620, P. R. China., Zhu XY; School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China., Gao DW; School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, P. R. China.; State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin, 300071, P. R. China.
Jazyk: angličtina
Zdroj: Angewandte Chemie (International ed. in English) [Angew Chem Int Ed Engl] 2024 Jan 25; Vol. 63 (5), pp. e202318441. Date of Electronic Publication: 2023 Dec 28.
DOI: 10.1002/anie.202318441
Abstrakt: The construction of acyclic, non-adjacent 1,3-stereogenic centers, prevalent motifs in drugs and bioactive molecules, has been a long-standing synthetic challenge due to acyclic nucleophiles being distant from the chiral environment. In this study, we successfully synthesized highly valuable 1,2-bis(boronic) esters featuring acyclic and nonadjacent 1,3-stereocenters. Notably, this reaction selectively produces migratory coupling products rather than alternative deborylative allylation or direct allylation byproducts. This approach introduces a new activation mode for selective transformations of gem-diborylmethane in asymmetric catalysis. Additionally, we found that other gem-diborylalkanes, previously challenging due to steric hindrance, also successfully participated in this reaction. The incorporation of 1,2-bis(boryl)alkenes facilitated the diversification of the alkenyl and two boron moieties in our target compounds, thereby enabling access to a broad array of versatile molecules. DFT calculations were performed to elucidate the reaction mechanism and shed light on the factors responsible for the observed excellent enantioselectivity and diastereoselectivity. These were determined to arise from ligand-substrate steric repulsions in the syn-addition transition state.
(© 2023 Wiley-VCH GmbH.)
Databáze: MEDLINE
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