使用 KO t Bu/1,10-菲咯啉采用热或光化学控制工艺建立了多环芳香二芳基胺和咔唑的化学发散合成方法。合成过程涉及9-氨基-10-(氧膦基)菲的脱氧膦基化,这是通过区域选择性钯催化的氧膦基胺与2-碘联苯的直接[4 + 2]苯环化反应获得的。当在加热条件(~100℃)下进行脱氧膦化时,会产生9-氨基菲。然而,当反应在紫光(LED,λ max = 约 390 nm)照射下进行时,KO t Bu/1,10-菲咯啉促进单电子转移触发的脱氧膦化,然后环化,产生相应的π-膨胀咔唑。我们通过双脱氧膦环化成功合成了高度π扩容的二咔唑。此外,我们还介绍了通过脱膦酰化过程产生的一系列氨基化合物的光学性质。
carbonylation reaction for the synthesis of fluoren‐9‐ones from 2‐halogenated biphenyls using phenyl formate as a carbon monoxide surrogate was achieved. The combined use of cesium carbonate and o‐anisic acid resulted in a remarkable rate enhancement, where the reaction was complete within 3 min in some cases. Mechanistic studies indicated that the turnover‐limiting step of the reaction was the C−H bond‐cleaving
A highly efficient palladium‐catalyzed disilylation reaction of arylhalides through C−H activation has been developed for the first time. The reaction has broad substrate scope. A variety of arylhalides can be disilylated by three types of C−H activation, including C(sp2)−H, C(sp3)−H, and remote C−H activation. In particular, the reactions are also unusually efficient. The yields are essentially
for the synthesis of fluorene and its derivatives starting from 2-iodobiphenyls and CH2Br2. A range of fluorene derivatives can be synthesized under relatively mild conditions. The reaction proceeds via a tandem palladium-catalyzed dual C–C bond formation sequence through the key dibenzopalladacyclopentadiene intermediates, which are obtained from 2-iodobiphenyls through palladium-catalyzed C–H activation
Highly Efficient Route to Fused Polycyclic Aromatics via Palladium-Catalyzed Aryne Annulation by Aryl Halides
作者:Zhijian Liu、Richard C. Larock
DOI:10.1021/jo0619534
日期:2007.1.1
Polycyclic aromatic and heteroaromatic hydrocarbons have been synthesized in high yield by two different processes involving the Pd-catalyzed annulation of arynes. The first process involves a Pd-catalyzed annulation of arynes by 2-halobiaryls and related vinylic halides. The second process utilizes a Pd-catalyzed double annulation of arynes by simple aryl halides. Both processes appear to involve
Broad activity of diphenyleneiodonium analogues against Mycobacterium tuberculosis, malaria parasites and bacterial pathogens
作者:Nghi Nguyen、Danny W. Wilson、Gayathri Nagalingam、James A. Triccas、Elena K. Schneider、Jian Li、Tony Velkov、Jonathan Baell
DOI:10.1016/j.ejmech.2017.10.010
日期:2018.3
evaluated primarily for in vitro efficacy against Gram-positive and Gram-negative bacteria, commonly responsible for nosocomial and community acquired infections. In addition, we also assessed the activity of these compounds againstMycobacteriumtuberculosis (Tuberculosis) and Plasmodium spp. (Malaria). This led to the discovery of highly potent compounds active against bacterial pathogens and malaria parasites