We reported a highly effective Pd-catalytic system for the synthesis of diarylbenzenes through Suzuki-type reactionbetween equal amount of diiodoarenes and arylboronicacids. This preferential oxidative addition resulted in such high selectivity.
Selective Mechanochemical Monoarylation of Unbiased Dibromoarenes by <i>in Situ</i> Crystallization
作者:Tamae Seo、Koji Kubota、Hajime Ito
DOI:10.1021/jacs.0c01739
日期:2020.6.3
Palladium-catalyzed Suzuki-Miyaura cross-coupling reactions of liquid, unbiased dibromoarenes under mechanochemical conditions selectively afford the monoarylated products. The lower reactivity of the crystalline monoarylated products rela-tive to the liquid starting materials should be attributed predom-inantly to the low diffusion efficiency of the former in the re-action mixture, which results in
Two Efficient Routes to m-Terphenyls from 1,3-Dichlorobenzenes
作者:Akbar Saednya、Harold Hart
DOI:10.1055/s-1996-4426
日期:1996.12
In the first route 2,6-dichlorophenyllithium (5), prepared by direct lithiation of 1,3-dichlorobenzene, reacted with aryl Grignard reagents to give m-terphenyls in 57-93% yields (Table 1); the methodology was extended to substituted 1,3-dichlorobenzenes (i.e. 8 → 10). Also, reaction of 5 with MgCl2 gave 2,6-dichlorophenylmagnesium chloride which, on warming, produced the self-capture product tetrachloro-m-terphenyl 7 in moderate yield. In the second route, reaction of 1,3-dichlorobenzene with excess of aryllithium in diethyl ether at room temperature gave the corresponding m-terphenyls in 59-94% yields (Table 2). Examples are given in which the aryllithium was prepared by three different routes (ArX+Li, ArX+t-BuLi, ArH+BuLi).