Pd-Catalyzed Suzuki–Miyaura and Hiyama–Denmark Couplings of Aryl Sulfamates
作者:Patrick R. Melvin、Nilay Hazari、Megan Mohadjer Beromi、Hemali P. Shah、Michael J. Williams
DOI:10.1021/acs.orglett.6b02330
日期:2016.11.18
Using a recently discovered precatalyst, the first Pd-catalyzed Suzuki–Miyaura reactions using aryl sulfamates that occur at room temperature are reported. In complementary work, it is demonstrated that a related precatalyst can facilitate the coupling of aryl silanolates, which are less toxic and reactive nucleophiles than boronic acids with aryl chlorides. By combining our results using modern electrophiles
Nickel- or Iron-Catalyzed Cross-Coupling of Aryl Carbamates with Arylsilanes
作者:Wen-Juan Shi、Hong-Wei Zhao、Yang Wang、Zhi-Chao Cao、Li-Sheng Zhang、Da-Gang Yu、Zhang-Jie Shi
DOI:10.1002/adsc.201600590
日期:2016.7.28
Aryl carbamates were for the first time applied as electrophiles in the cross‐coupling with arylsilanes via nickel or iron catalysis to construct valuable biaryl compounds. This new coupling reaction features a good group tolerance and non‐sensitivity to steric hindrance on both aryl carbamates and arylsilanes.
Synthesis of unsymmetrical biaryls via kinetic higher order cyanocuprates: scope, limitations, and spectroscopic insights
作者:Bruce H. Lipshutz、Konstantin Siegmann、Emiliano Garcia、Frank Kayser
DOI:10.1021/ja00073a051
日期:1993.10
Treatment of lower order arylcyanocuprates ArCu(CN)Li with 1 equiv of an aryllithium (Ar'Li) at temperatures around -125 o C leads to higherorder reagents Ar(Ar')Cu(CN)Li 2 . Upon exposure of such reagents at this temperature to ground-state molecular oxygen, good yields of the unsymmetrical biaryl Ar-Ar' can be realized. Several different types of aryl ligands have been examined, including naphthalenes
在 -125 o C 左右的温度下,用 1 当量的芳基锂 (Ar'Li) 处理低级芳基氰铜酸盐 ArCu(CN)Li 会产生高级试剂 Ar(Ar')Cu(CN)Li 2 。在该温度下将此类试剂暴露于基态分子氧后,可以实现不对称联芳基 Ar-Ar' 的良好产率。已经检查了几种不同类型的芳基配体,包括萘,以评估该方法的通用性。已经在 -130 o C 和更高温度下获得了三种不同铜酸盐的光谱数据( 13 C NMR),以确定它们的动力学性质(如合成化学所示)是否可以通过物理方法证实
Decarboxylation, during their aromatization by Pd/C, of some 3,4-octahydronaphtho-7,8-benzocoumarins
作者:K. Chebaane、M. Guyot
DOI:10.1016/0040-4020(77)80188-9
日期:1977.1
Some 3',4'-cyclohexa-1',2'-dihydro- and 1',2'-cyclohexa-3',4'-dihydro-3,4,7,8-dibenzocoumarins 2 and 3 were prepared by catalytic condensation between a naphthol and a α-carbethoxy-cis- decalone (−1 or −2). These compounds, when treated with Pd/C at 260°, undergo, beside aromatization, a complete decarboxylation of the lactone ring. A mechanism, involving H transfer through a π-allylic palladium complex