O-Dihaloarenes as aryne precursors for nickel-catalyzed [2 + 2 + 2] cycloaddition with alkynes and nitriles
作者:Jen-Chieh Hsieh、Chien-Hong Cheng
DOI:10.1039/b801870g
日期:——
o-Dihaloarenes acting as aryne precursors react with acetylenes and nitriles catalyzed by the NiBr(2)(dppe)/dppe/Zn system to give substituted naphthalene, phenanthridine or triphenylene derivatives depending on the reaction conditions in moderate to excellent yields with good tolerance of functional groups.
Rhodium‐Catalyzed [2+1+2+1] Cycloaddition of Benzoic Acids with Diynes through Decarboxylation and C≡C Triple Bond Cleavage
作者:Yusaku Honjo、Yu Shibata、Ken Tanaka
DOI:10.1002/chem.201901050
日期:2019.7.17
an electron‐deficient cyclopentadienyl rhodium(III) (CpERhIII) complex catalyzes the oxidative and decarboxylative [2+1+2+1] cycloaddition of benzoic acids with diynes through C≡C triple bond cleavage, leading to fused naphthalenes. This cyclotrimerization is initiated by directed ortho C−H bond cleavage of a benzoic acid, and the subsequent regioselective alkyne insertion and decarboxylation produce
unfunctionalized arenes with 1,6-diynes, possessing aryl groups at the diyne termini, proceeds to give the corresponding dienylated arenes in the presence of a catalytic amount of an electron-deficient cyclopentadienyl rhodium(III) complex, [CpERhCl2]2, and a stoichiometric amount of silver carbonate. Experimental and theoretical mechanisticstudies revealed that a CpERh(I) complex generated in situ