TY - JOUR
T1 - Iridium-catalyzed selective 1,2-hydrosilylation of N-heterocycles
AU - Jeong, Jinseong
AU - Park, Sehoon
AU - Chang, Sukbok
N1 - Publisher Copyright:
© 2016 The Royal Society of Chemistry.
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 -