Synthesis of Substituted Benzenes via Bi(OTf)3-Mediated Intramolecular Carbonyl Allylation of α-Prenyl or α-Geranyl β-Arylketosulfones
摘要:
Intramolecular carbonyl allylation of alpha-prenyl or alpha-geranyl beta-arylketosulfones 5 in the presence of molecule sieves (MS) affords substituted benzenes 6-7 in moderate to good yields. The facile transformation proceeds by a synthetic sequence starting with the alpha-prenylation or alpha-geranylation of 1 and the Bi(OTf)(3)-mediated annulation of 5 followed by a sequential desulfonative aromatization or then an intramolecular FriedelCrafts alkylation. A plausible mechanism has been studied and proposed.
species. It was also applicable as a chemoselective hydrogenation catalyst, showing inactivity for the hydrogenolysis of tert‐butyldimethylsilyl (TBS) ethers, alkyl benzyl ethers, and benzyl alcohols. The tert‐amines on WA30 acted as moderate catalyst poisons for Pd, resulting in chemoselective hydrogenation. 7% Pd/WA30 was reused for at least five times without any loss of the hydrogenation catalytic
A highly active catalytic system for Suzuki–Miyaura cross-coupling reactions of aryl and heteroaryl chlorides in water
作者:Shu-Lan Mao、Yue Sun、Guang-Ao Yu、Cui Zhao、Zhi-Jun Han、Jia Yuan、Xiaolei Zhu、Qihua Yang、Sheng-Hua Liu
DOI:10.1039/c2ob26463c
日期:——
An easily available Pd(OAc)2/(2-mesitylindenyl)dicyclohexylphosphine/Me(octyl)3N+Cl−/K3PO4·3H2O catalytic system was developed and it shows high catalytic activity in the Suzuki–Miyaura cross-coupling reaction of a diverse array of aryl and heteroaryl chlorides in water. Notably, this catalytic system also works with ultra-low loading of the catalyst with high turnover numbers.
容易获得的Pd(OAc)2 /(2-异丁烯基)二环己基膦/ Me的(辛基)3 Ñ +氯- / K 3 PO 4 ·3H 2 ö催化体系被开发,它示出了在芳基和杂芳基氯化物的多样性阵列的Suzuki-Miyaura交叉偶联反应的高催化活性水。值得注意的是,该催化系统还可以在超低负荷下以高周转数运行。
Nickel-Catalyzed Cross-Coupling of Aryl Phosphates with Arylboronic Acids
The Suzuki−Miyaura cross-coupling of aryl phosphates using Ni(PCy3)2Cl2 as an inexpensive, bench-stable catalyst is described. Broad substrate scope and high efficiency are demonstrated by the syntheses of more than 40 biaryls and by constructing complex organic molecules. The poor reactivity of aryl phosphates relative to aryl halides is successfully employed to construct polyarenes by selective cross-coupling
Iridium-Catalyzed<i>ortho</i>-Arylation of Benzoic Acids with Arenediazonium Salts
作者:Liangbin Huang、Dagmar Hackenberger、Lukas J. Gooßen
DOI:10.1002/anie.201505769
日期:2015.10.19
In the presence of catalytic [IrCp*Cl2}2] and Ag2CO3, Li2CO3 as the base, and acetone as the solvent, benzoic acids react with arenediazonium salts to give the corresponding diaryl‐2‐carboxylates under mild conditions. This CH arylation process is generally applicable to diversely substituted substrates, ranging from extremely electron‐rich to electron‐poor derivatives. The carboxylate directing
在催化[IrCp * Cl 2 } 2 ]和Ag 2 CO 3,Li 2 CO 3为碱,丙酮为溶剂的情况下,苯甲酸与槟榔重氮盐反应生成相应的二芳基-2-羧酸盐温和的条件。这种CH芳基化过程通常适用于各种取代的底物,范围从极富电子的至贫电子的衍生物。羧酸根导向基团是广泛可得的,可以无痕地除去或用于进一步的衍生作用。通过使用重氮盐可实现与卤化物交叉偶联的正交性,即使存在碘取代基也可将其偶联。
<i>N</i>-Heterocyclic Carbene Coordinated Heterogeneous Pd Nanoparticles as Catalysts for Suzuki–Miyaura Coupling
作者:Hyemin Min、Hiroyuki Miyamura、Shū Kobayashi
DOI:10.1246/cl.160369
日期:2016.7.5
Palladium nanoparticle (Pd NP) catalysts immobilized in a polymer with an N-heterocycliccarbene (NHC) moiety (PICB-NHC-Pd) have been developed, wherein the NHC moiety plays dual roles as a crosslinker and a ligand to activate the Pd NPs. The presence of both Pd NPs and NHC was confirmed by STEM/EDS and SR-MAS NMR analyses, respectively. This PICB-NHC-Pd catalyst showed excellent activity in the Suzuki–Miyaura