Cross‐Si‐ing the Jordan: Cross‐coupling reactions of 2‐(2‐hydroxyprop‐2‐yl)phenyl‐substituted alkylsilanes with a variety of aryl halides proceed in the presence of palladium and copper catalysts. The use of K3PO4 base allows for highly chemoselective alkyl coupling with both primary and secondary alkyl groups (Alk).
乔丹的交叉反应:2-(2-羟基丙-2-基)苯基取代的烷基硅烷与各种芳基卤化物的交叉偶联反应在钯和铜催化剂的存在下进行。K 3 PO 4碱的使用允许与伯烷基和仲烷基(Alk)都高度化学选择性的烷基偶联。
Iron–Nickel Dual-Catalysis: A New Engine for Olefin Functionalization and the Formation of Quaternary Centers
作者:Samantha A. Green、Suhelen Vásquez-Céspedes、Ryan A. Shenvi
DOI:10.1021/jacs.8b05868
日期:2018.9.12
electron-deficient arenes, including Lewis basic heterocycles. Here we report a highly Markovnikov-selective, dual-catalytic olefin hydroarylation that tolerates arenes and heteroarenes of any electronic character. Hydrogen atom transfer controls the formation of branched products and arene halogenation specifies attachment points on the aromatic ring. Mono-, di-, tri-, and tetra-substituted alkenes yield Markovnikov
Mild Negishi Cross-Coupling Reactions Catalyzed by Acenaphthoimidazolylidene Palladium Complexes at Low Catalyst Loadings
作者:Zelong Liu、Ningning Dong、Mizhi Xu、Zheming Sun、Tao Tu
DOI:10.1021/jo400803s
日期:2013.8.2
3a exhibited extremely high catalytic activity toward Negishicross-coupling of alkylzinc reagents with a wide range of (hetero)arylhalides under mild reaction conditions within 30 min. Besides a great number of bromoarenes, various less expensive and inactive (hetero)aryl chlorides were coupled successfully with the alkyl- and arylzincreagents, in which active functional groups (such as -NH2) were
考虑到衍生自π-延伸的咪唑鎓盐的亚烷基的强大的σ-供体性质有利于提高所得钯N-杂环卡宾配合物的催化活性,因此制备了具有健壮的并咪唑-亚烷基钯配合物3a - c,具有不同的大取代基团通过在纯净的3-氯吡啶中与PdCl 2和K 2 CO 3加热,从相应的啶咪唑氯化物中得到满意的收率。即使在催化剂负载量低至0.25 mol%的情况下,配合物3a在温和的反应条件下,在30分钟内显示出对烷基锌试剂与各种(杂)芳基卤化物的Negishi交叉偶联极高的催化活性。除了大量的溴代芳烃外,还成功地将各种较便宜且不活泼的(杂)芳基氯化物与烷基-和芳基锌试剂偶联,其中具有活性官能团(例如-NH 2))即使在无保护的一锅双偶转换中也具有良好的耐受性。此外,在与仲烷基锌试剂偶联的情况下,有效抑制了导致异构化的线性产物的不希望的β-氢化物消除。通过杂芳基锌试剂和杂环氯代芳烃的偶联,该催化剂体系还显示出在杂二芳基结构方面
The invention relates to novel compounds having the general formula (I), and which compounds are useful to treat a disorder or disease characterized by bronchoconstriction, e.g. COPD and asthma.
Ruphos-mediated Suzuki cross-coupling of secondary alkyl trifluoroborates
作者:Adri van den Hoogenband、Jos H.M. Lange、Jan Willem Terpstra、Melle Koch、Gerben M. Visser、Martin Visser、Ties J. Korstanje、Johann T.B.H. Jastrzebski
DOI:10.1016/j.tetlet.2008.04.129
日期:2008.6
A Ruphos-mediated Suzukicross-coupling between (hetero)aryl bromides and secondary alkyltrifluoroborates is described using palladium catalysis. The Ruphos ligand showed superior properties as compared to S-Phos in this type of reaction. This method constitutes a valuable extension to current methods for the straightforward production of secondary-alkylated (hetero)aryl derivatives.