A Pd/C-catalyzed deoxygenationmethod of phenolic hydroxyl groups via aryl triflates or mesylates using Mg metal in MeOH at room temperature was developed. The addition of NH4OAc dramatically affects the reactivity and reaction rate. This method is particularly attractive to provide an environmentally benign and widely applicable removal method of phenolic alcohols under quite mild reaction conditions
method for the deoxygenation of phenolic hydroxy groups via aryl triflates or mesylates has been established by using a combination of Pd/C-Mg-MeOH. The addition of NH(4)OAc to the system markedly accelerated the reaction rate and expanded the scope of the reaction. Mechanistic studies suggested that a single-electron transfer process from the Pd(0) center to the benzene ring is involved in the reduction
A novel and efficient catalyst system was developed for homocouplingreactions of aryl halides. The catalyst system consists of Pd(OAc)2 and the peppery sensory component of tobacco leaves. This is the first time that a sensory component has been used in an organic reaction. Experiments using the catalyst system showed that the reactions proceeded smoothly under air in the absence of both an additional
Thieme Journal Awardees - Where Are They Now? On Cobalt-Catalyzed Biaryl Coupling Reactions
作者:Axel Jacobi von Wangelin、Matthias Mayer、Waldemar Czaplik
DOI:10.1055/s-0029-1218013
日期:2009.11
An operationally simple biaryl coupling reaction has been developed. The underlying domino process involves in situGrignard formation from aryl bromides and subsequent homocoupling with catalytic CoCl 2 and I bar synthetic air as terminal oxidant.
已开发出操作简单的联芳基偶联反应。潜在的多米诺骨牌过程涉及由芳基溴化物原位形成格氏,随后与催化 CoCl 2 和 I bar 合成空气作为末端氧化剂均偶联。
Aerobic Homocoupling of Arylboronic Acids Catalyzed by Regenerable Pd(II)@MIL‐88B‐NH
<sub>2</sub>
(Cr)
A fast and operationally simple method for the aerobic homocoupling of arylboronic acids is described. The process is catalyzed by Pd(II) complexes supported on the metal‐organic framework MIL‐88B‐NH2(Cr). The benefits of this approach include the use of a benign oxidant/solvent mixture at room temperature with catalytic amounts of base, easy recovery of the catalyst, and easy isolation of the products