Cobalt-Catalyzed Negishi Cross-Coupling Reactions of (Hetero)Arylzinc Reagents with Primary and Secondary Alkyl Bromides and Iodides
作者:Jeffrey M. Hammann、Diana Haas、Paul Knochel
DOI:10.1002/anie.201411960
日期:2015.4.7
di(hetero)arylzinc reagents with primary and secondaryalkyliodides or bromides using THF‐soluble CoCl2⋅2 LiCl and TMEDA as a ligand, which leads to the corresponding alkylated products in up to 88 % yield. A range of functional groups (e.g. COOR, CN, CF3, F) are tolerated in these substitution reactions. Remarkably, we do not observe rearrangement of secondaryalkyliodides to unbranched products. Additionally
Preparation of Functionalized Aryl Iron(II) Compounds and a Nickel-Catalyzed Cross-Coupling with Alkyl Halides
作者:Stefan H. Wunderlich、Paul Knochel
DOI:10.1002/anie.200905196
日期:2009.12.14
The ortho‐ferration of functionalizedarenesusing tmp2Fe⋅2MgCl2⋅4LiCl furnishes the corresponding diorgano FeII reagents at 25 °C in high yields. These reagents undergo cross‐coupling reactions in the presence of 4‐fluorostyrene to give various alkylated arenes. It turned out that NiII impurities present in commercial FeCl2 (98 % pure) catalyzed this alkyl–aryl cross‐coupling reaction.