An Electron-Deficient Diene as Ligand for Palladium-Catalyzed Cross-Coupling Reactions: An Efficient Alkylation of Aryl Iodides by Primary and Secondary Alkylzinc Reagents
作者:Qiang Liu、Hui Duan、Xiancai Luo、Yang Tang、Gang Li、Rong Huang、Aiwen Lei
DOI:10.1002/adsc.200800118
日期:2008.6.9
An electron-deficientdiene, L1, was found to be an effective ligand in facilitating palladium-catalyzed Negishi couplings involving primary and secondaryalkylzincreagents. The reactions took place readily at 60 °C in THF with 5 mol% of a catalyst generated in situ from bis(acetonitrile)palladium dichloride [PdCl2(MeCN)2] and L1, and functional groups such as chloro, bromo, etc. attached to phenyl
Effective Pd-Nanoparticle (PdNP)-Catalyzed Negishi Coupling Involving Alkylzinc Reagents at Room Temperature
作者:Jing Liu、Yi Deng、Haibo Wang、Hua Zhang、Ganxiang Yu、Bingbin Wu、Heng Zhang、Qiang Li、Todd B. Marder、Zhen Yang、Aiwen Lei
DOI:10.1021/ol8007342
日期:2008.7.3
Pd(OAc)(2) is an efficient catalyst precursor for Negishi coupling in the presence of Bu4NBr. Secondary and primary alkylzinc reagents with beta-H and arylzinc reagents all reacted with aryl iodides at temperatures as low as -20 degrees C, giving moderate to good yields. One example of coupling between alkynylzinc reagents and aryl iodides was tested and the yield was good. Preliminary kinetic studies indicated that the process involved PdNPs as the active catalytic species.
Pincer Thioamide and Pincer Thioimide Palladium Complexes Catalyze Highly Efficient Negishi Coupling of Primary and Secondary Alkyl Zinc Reagents at Room Temperature
作者:Haibo Wang、Jing Liu、Yi Deng、Tianyin Min、Ganxiang Yu、Xiaojun Wu、Zhen Yang、Aiwen Lei
DOI:10.1002/chem.200801860
日期:2009.1.26
structures of complexes 2 and 3 were confirmed by X‐ray analysis. Both complexes are efficient catalysts for Negishicouplings involving primary and secondary alkyl zinc reagents bearing β‐hydrogen atoms. At a concentration of 0.1–0.5 mol % both catalysts readily promoted reactions at roomtemperature or even at 0 °C. The operational simplicity of these processes, in conjunction with the easy accessibility