An efficient organocatalytic method for constructing biaryls through aromatic C-H activation.
The direct functionalization of C-H bonds has drawn the attention of chemists for almost a century. C-H activation has mainly been achieved through four metal-mediated pathways: oxidative addition, electrophilic substitution, σ-bond metathesis and metal-associated carbene/nitrene/oxo insertion. However, the identification of methods that do not require transition-metal catalysts is important because methods involving such catalysts are often expensive. Another advantage would be that the requirement to remove metallic impurities from products could be avoided, an important issue in the synthesis of pharmaceutical compounds. Here, we describe the identification of a cross-coupling between aryl iodides/bromides and the C-H bonds of arenes that is mediated solely by the presence of 1,10-phenanthroline as catalyst in the presence of KOt-Bu as a base. This apparently transition-metal-free process provides a new strategy with which to achieve direct C-H functionalization.
Beijing National Laboratory of Molecular Sciences (BNLMS) and Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
Chang-Liang
CL
Sun
Hu
H
Li
Da-Gang
DG
Yu
Miao
M
Yu
Xiao
X
Zhou
Xing-Yu
XY
Lu
Kun
K
Huang
Shu-Fang
SF
Zheng
Bi-Jie
BJ
Li
Zhang-Jie
ZJ
Shi
D001965:Bromides / Q000737:chemistry; D000440:Butanols / Q000737:chemistry; D002244:Carbon / Q000737:chemistry*; D002384:Catalysis; D006859:Hydrogen / Q000737:chemistry*; D007454:Iodides / Q000737:chemistry; D007700:Kinetics; D010618:Phenanthrolines / Q000737:chemistry; D028561:Transition Elements / Q000737:chemistry
D001965:Bromides; D000440:Butanols; D007454:Iodides; D010618:Phenanthrolines; D028561:Transition Elements; D002244:Carbon; D006859:Hydrogen; C077664:tert-butoxide, potassium; C025205:1,10-phenanthroline