Iridium-catalyzed Selective 1,2-hydrosilylation of N-heterocycles

Overview

Journal Chem Sci

Publisher Royal Society of Chemistry

Specialty Chemistry

Date 2018 Aug 30

PMID 30155189

Citations 4

Authors

Jinseong Jeong

Sehoon Park

Sukbok Chang

Affiliations

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Abstract

A silylene-bridged Ir dimer generated from [Ir(coe)Cl] and EtSiH was found to catalyze the hydrosilylation of N-heteroaromatics to furnish dearomatized azacyclic products with high activity (up to 1000 TONs), excellent selectivity, and good functional group tolerance. The substrate scope was highly broad, including (iso)quinolines, substituted pyridines, pyrimidines, pyrazines, deazapurines, triazines, and benzimidazoles. Mechanistic studies such as a kinetic profile, rate-order assessment, and investigation of the electronic substituent effects on the initial rates were performed to access the detailed pathways. One pathway is proposed to involve an intramolecular insertion of the C[double bond, length as m-dash]N moiety of the substrates into the Ir-H bond of a resting species to form an Ir-amido silyl intermediate, followed by reductive elimination. The synthetic utility was proven by successful application to alkaloids, and facile post-synthetic transformations of the 1,2-dihydroquinoline products.

Citing Articles

Synthesis and utility of -boryl and -silyl enamines derived from the hydroboration and hydrosilylation of -heteroarenes and -conjugated compounds.

Cao V, Joung S Front Chem. 2024; 12:1414328.

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Recent Strategies in the Nucleophilic Dearomatization of Pyridines, Quinolines, and Isoquinolines.

Escolano M, Gavina D, Alzuet-Pina G, Diaz-Oltra S, Sanchez-Rosello M, Del Pozo C Chem Rev. 2024; 124(3):1122-1246.

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Tandem Dearomatization/Enantioselective Allylic Alkylation of Pyridines.

Gressies S, Susse L, Casselman T, Stoltz B J Am Chem Soc. 2023; 145(22):11907-11913.

PMID: 37212659 PMC: 10251512. DOI: 10.1021/jacs.3c02470.

An umpolung approach to the hydroboration of pyridines: a novel and efficient synthesis of -H 1,4-dihydropyridines.

Yang H, Zhang L, Zhou F, Jiao L Chem Sci. 2021; 11(3):742-747.

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