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

Jinseong Jeong; Sehoon Park; Sukbok Chang

doi:10.1039/c6sc01037g

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

Jinseong Jeong, Sehoon Park^*, Sukbok Chang

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

36 Scopus citations

Abstract

A silylene-bridged Ir dimer in situ generated from [Ir(coe)₂Cl]₂ and Et₂SiH₂ 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 CN 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 cinchona alkaloids, and facile post-synthetic transformations of the 1,2-dihydroquinoline products.

Original language	English
Pages (from-to)	5362-5370
Number of pages	9
Journal	Chemical Science
Volume	7
Issue number	8
DOIs	https://doi.org/10.1039/c6sc01037g
State	Published - 2016
Externally published	Yes

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title = "Iridium-catalyzed selective 1,2-hydrosilylation of N-heterocycles",

abstract = "A silylene-bridged Ir dimer in situ generated from [Ir(coe)2Cl]2 and Et2SiH2 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 CN 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 cinchona alkaloids, and facile post-synthetic transformations of the 1,2-dihydroquinoline products.",

author = "Jinseong Jeong and Sehoon Park and Sukbok Chang",

note = "Publisher Copyright: {\textcopyright} 2016 The Royal Society of Chemistry.",

year = "2016",

doi = "10.1039/c6sc01037g",

language = "英语",

volume = "7",

pages = "5362--5370",

journal = "Chemical Science",

issn = "2041-6520",

publisher = "Royal Society of Chemistry",

number = "8",

}

TY - JOUR

T1 - Iridium-catalyzed selective 1,2-hydrosilylation of N-heterocycles

AU - Jeong, Jinseong

AU - Park, Sehoon

AU - Chang, Sukbok

PY - 2016

Y1 - 2016

N2 - A silylene-bridged Ir dimer in situ generated from [Ir(coe)2Cl]2 and Et2SiH2 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 CN 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 cinchona alkaloids, and facile post-synthetic transformations of the 1,2-dihydroquinoline products.

AB - A silylene-bridged Ir dimer in situ generated from [Ir(coe)2Cl]2 and Et2SiH2 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 CN 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 cinchona alkaloids, and facile post-synthetic transformations of the 1,2-dihydroquinoline products.

UR - http://www.scopus.com/inward/record.url?scp=84979529974&partnerID=8YFLogxK

U2 - 10.1039/c6sc01037g

DO - 10.1039/c6sc01037g

M3 - 文章

AN - SCOPUS:84979529974

SN - 2041-6520

VL - 7

SP - 5362

EP - 5370

JO - Chemical Science

JF - Chemical Science

IS - 8

ER -

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

Abstract

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