Palladium-catalyzed cyclocoupling of 2-halobiaryls with isocyanides via the cleavage of carbon-hydrogen bonds.
To demonstrate the utility of isocyanides in catalytic C-H bond functionalization reactions, a palladium-catalyzed cyclocoupling reaction of 2-halobiaryls with isocyanides was developed. The reaction afforded an array of fluorenone imine derivatives via the cleavage of a C-H bond at the 2'-position of 2-halobiaryls. The use of 2,6-disubstituted phenyl isocyanide was crucial for this catalytic cyclocoupling reaction to proceed. The reaction was applicable to heterocyclic and vinylic substrates, allowing the construction of a wide range of ring system. The large kinetic isotope effect observed (k(H)/k(D) = 5.3) indicates that C-H bond activation was the turnover-limiting step in this catalysis.
Tobisu
Mamoru
M
Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
Imoto
Shinya
S
Ito
Sana
S
Chatani
Naoto
N