Borane-Catalyzed Chemoselective and Enantioselective Reduction of 2-Vinyl-Substituted Pyridines.

Angew Chem Int Ed Engl

State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin, 300071, China.

Published: October 2020

Herein, we report that highly chemoselective and enantioselective reduction of 2-vinyl-substituted pyridines has been achieved for the first time. The reaction, which uses chiral spiro-bicyclic bisboranes as catalysts and HBpin and an acidic amide as reducing reagents, proceeds through a cascade process involving 1,4-hydroboration followed by transfer hydrogenation of a dihydropyridine intermediate. The retained double bond in the reduction products permits their conversion to natural products and other useful heterocyclic compounds by simple transformations.

Download full-text PDF

Source
http://dx.doi.org/10.1002/anie.202007352DOI Listing

Publication Analysis

Top Keywords

chemoselective enantioselective
8
enantioselective reduction
8
reduction 2-vinyl-substituted
8
2-vinyl-substituted pyridines
8
borane-catalyzed chemoselective
4
pyridines report
4
report highly
4
highly chemoselective
4
pyridines achieved
4
achieved time
4

Similar Publications

Ionic liquid (IL) units in heterogeneous catalysts exhibit synergistic effects to enhance catalytic performance and stabilize catalytically active centers, while also preventing the degradation of catalysts during the reaction process. Ionic liquid units in IL-functionalized CMOF catalysts enhance their catalytic performance in a synergistic manner. However, not only are the yields of IL-functionalized CMOFs obtained with post-synthesis methods low, but they also lead to blocking of the MOF pores and leaching of the ionic liquid.

View Article and Find Full Text PDF
Article Synopsis
  • * These innovative methods utilize a redox process, allowing for the production of organometallic nucleophiles without needing traditional reagents like carbonyl additives or chiral auxiliaries.
  • * The approach allows selective dehydrogenation of primary alcohols when secondary alcohols are present, facilitating carbon-carbon coupling without the need for protecting groups.
View Article and Find Full Text PDF

Asymmetric S-Arylation of Sulfenamides to Access Axially Chiral Sulfilimines Enabled by Anionic Stereogenic-at-Cobalt(III) Complexes.

Angew Chem Int Ed Engl

December 2024

Department of Applied Chemistry, Anhui Province Engineering Laboratory for Green Pesticide Development and Application, and Anhui Province Key Laboratory of Crop Integrated Pest Management, Anhui Agricultural University, Hefei, 230036, China.

An efficient enantioselective coupling reaction between sulfenamides and cyclic diaryliodonium salts is established via adaptive Cu/anionic stereogenic-at-Co(III) complex combined catalysis, precisely synthesizing a broad range of axially chiral sulfilimines with excellent enantioselectivities, diastereoselectivities, regioselectivities, and chemoselectivities (67 examples under same conditions, up to 98 % ee). The following thermodynamically controlled pyramidal inversion enables efficient stereodivegent synthesis of all four stereoisomers. Mechanistic studies suggest that anionic stereogenic-at-cobalt(III) complexes serve as counteranions of diaryliodonium and anionic ligand of Cu(I) catalyst simultaneously, which could be regarded as an explanation for outstanding selectivities.

View Article and Find Full Text PDF

Dynamic amine sorting enables multiselective construction of unsymmetrical chiral diamines.

Nat Chem

December 2024

Key Laboratory of Precision and Intelligent Chemistry, Department of Chemistry, University of Science and Technology of China, Hefei, P. R. China.

Precisely differentiating chemicals featuring minor discrepancies is the prerequisite for achieving high selectivities in both chemical synthesis and biological activities. However, efficient strategies to differentiate and sort such congeneric compounds are lacking, posing daunting challenges for synthetic endeavours aimed at their orderly incorporation. Here we report a dynamic amine-sorting strategy that incorporates the chemoselective formation of the aminomethyl cyclopalladated complex to achieve the efficient differentiation of amine congeners.

View Article and Find Full Text PDF

We describe the development of a unified synthetic strategy for the preparation of all known 5/5-spirocyclic spiroindimicin (SPM) alkaloids, namely spiroindimicins B-G. The present synthetic route relies on four fundamental transformations: Grignard-based fragment coupling between halogenated pyrrolemetal and isatin partners, Suzuki coupling to generate a triaryl scaffold encompassing all requisite skeletal atoms of the natural products, Lewis acid-mediated spirocyclization to construct the 5/5-spirocyclic core, and chemoselective lactam reduction. The developed syntheses are step-economic (6-7 steps from commercial materials), scalable, and amenable to analogue synthesis.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!