Catalyst Controlled Divergent C4/C8 Site-Selective C-H Arylation of Isoquinolones
Soyoung Lee1,2, Shinmee Mah1,2, Sungwoo Hong1,2
1†Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Korea.
Abstract:
The catalyst-controlled C4/C8 site-selective C-H arylation of isoquinolones using aryliodonium salts as the coupling partners was developed. The C4-selective arylation was successfully achieved via an electrophilic palladation pathway. A completely different selectivity pattern was observed using an Ir(III) catalytic system, which resulted in C-C bond formation exclusively at the C8 position. The isoquinolone scaffold can be conveniently equipped with various aryl substituents at either the C4 or C8 position.
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