A highly efficient and aerobic protocol for the synthesis of N-heteroaryl substituted 9-arylcarbazolyl derivatives via a palladium-catalyzed ligand-free Suzuki reaction.
A palladium-catalyzed aerobic and ligand-free Suzuki reaction in aqueous ethanol has been developed for the synthesis of N-heteroaryl substituted 9-arylcarbazolyl derivatives. A number of N-heteroaryl halides, namely 2-halogenated pyridines, 2-bromoquinoline, 5-bromopyrimidine and 2-chloropyrazine, were coupled with 4-(9H-carbazol-9-yl)phenylboronic acid (CPBA) or 9-phenyl-9H-carbazol-3-ylboronic acid (PCBA) efficiently to afford good to excellent yields in a short reaction time. Moreover, the catalytic system of Pd(OAc)(2)-EtOH/H(2)O-K(2)CO(3) was successfully extended to the cross-couplings of N-heteroaryl halides with various arylboronic acids. The results demonstrated that the cross-coupling reaction in the present protocol was promoted by oxygen.
State Key Laboratory of Fine Chemicals, Dalian University of Technology, Linggong Road 2, Dalian, 116024, China.
Xiaofeng
X
Rao
Chun
C
Liu
Jieshan
J
Qiu
Zilin
Z
Jin
D002227:Carbazoles / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry*
D002227:Carbazoles; D009942:Organometallic Compounds; D010165:Palladium