1619236-71-3Relevant articles and documents
Palladium-Catalyzed sp2 C-H Arylation of Azoarenes with Arylhydrazines
Li, Mingyang,Ye, Yong
, p. 4137 - 4142 (2015/12/26)
Transition-metal-catalyzed direct functionalization of C-H bonds is important for new compound synthesis, but usually needs special reagents and harsh conditions. With the aid of an azo directing group, the palladium-catalyzed ortho-sp2 C-H bond activation of azoarenes with hydrazines has been explored. In the reaction, the Pd catalyst reacts with azobenzene to form a palladacyclic intermediate, which reacts with a phenyl radical generated from phenylhydrazine under heating and oxygen to produce a PdIV or PdIII intermediate. This finally undergoes reductive elimination to give the ortho-arylated products with the release of the PdII catalyst. This reaction provides a novel access to ortho-aryl azoarenes under mild conditions in high yield. Helpful hydrazines: With the aid of an azo directing group, the palladium-catalyzed ortho-sp2 C-H bond activation of azoarenes with hydrazines has been explored. The catalyst reacts with azobenzene to form a palladacyclic intermediate, which reacts with a phenyl radical generated from phenylhydrazine produce a PdIV or PdIII intermediate. This undergoes reductive elimination to give the ortho-arylated products and regenerate the catalyst. This reaction provides a novel access to ortho-aryl azoarenes under mild conditions in high yield.
