Decatungstate as Direct Hydrogen Atom Transfer Photocatalyst for SOMOphilic Alkynylation
作者:Luca Capaldo、Davide Ravelli
DOI:10.1021/acs.orglett.1c00381
日期:2021.3.19
A versatile approach for the alkynylation of a variety of aliphatic hydrogen donors, including alkanes, is reported. We used tetrabutylammonium decatungstate as photocatalyst to generate organoradicals from C–H/Si–H bondsvia hydrogen atom transfer. The latter intermediates underwent SOMOphilic alkynylation by methanesulfonyl alkynes to afford internal alkynes upon loss of a sulfonyl radical. The effect
A general two-step one-pot synthesis process of ynones from α-keto acids and 1-iodoalkynes
作者:Xiaobao Zeng、Chulong Liu、Weiguang Yang、Xingyong Wang、Xinyan Wang、Yuefei Hu
DOI:10.1039/c8cc05429k
日期:——
A general two-step one-pot synthesis process of ynones was developed by cycloaddition of α-keto acids and 1-iodoalkynes followed by a ring-opening reaction. Its easy conditions and novel mechanism endowed it with two distinctive advantages: iodine-atom bonded to C(sp2) remained intact and α-keto acids became a part of the triple bonds in ynones.
Pd-Catalyzed Cross-Coupling of Terminal Alkynes with Chromium(0) Fischer Carbene Complexes
作者:Kang Wang、Fengjin Wu、Yan Zhang、Jianbo Wang
DOI:10.1021/acs.orglett.7b01096
日期:2017.6.2
Alkyl chromium(0) carbenecomplexes typically undergo cycloadditions with alkynes to afford carbo- or heterocyclic compounds. In the presence of Pd catalyst, it is demonstrated that a traditional cycloaddition pathway is completely altered: instead of cycloaddition, oxidative cross-coupling reaction of alkyl chromium(0) carbenecomplexes with terminal alkynes occurs. The coupling reaction exhibits
Transition-metal-free C–N and C–C formation: synthesis of benzo[4,5]imidazo[1,2-<i>a</i>]pyridines and 2-pyridones from ynones
作者:Qing-Hu Teng、Xiang-Jun Peng、Zu-Yu Mo、Yan-Li Xu、Hai-Tao Tang、Heng-Shan Wang、Hong-Bin Sun、Ying-Ming Pan
DOI:10.1039/c8gc00069g
日期:——
been revealed. This cascade reaction involved a Michael addition/intramolecular cycloaddition/dehydration and provided the desired benzo[4,5]imidazo[1,2-a]pyridines in moderate to good yield. Furthermore, three benzo[4,5]imidazo[1,2-a]pyridines (3d, 3i, and 3q) exhibited good activities against Hep-G2 (human liver cancer), T-24 (human bladder cancer cell), and SK-OV-3 (human ovarian cancer) cell lines
在此,已经揭示了在温和条件下炔烃与2-甲基苯并咪唑的无过渡金属的有效级联反应。该级联反应涉及迈克尔加成/分子内环加成/脱水,并以中等至良好的产率提供了所需的苯并[4,5]咪唑并[1,2- a ]吡啶。此外,三种苯并[4,5]咪唑并[1,2- a ]吡啶(3d,3i和3q)对Hep-G2(人类肝癌),T-24(人类膀胱癌细胞)和SK-OV-3(人类卵巢癌)细胞系,IC 50值在8.05–10.67μmolL -1范围内。为了研究有效抑制细胞生长的机制,对细胞周期分析,凋亡率检测,Ca 2+生成的测量,ROS,线粒体膜电位测定和caspase-3 / 9活化进行了进一步的研究。化合物3i。
Hypervalent organoantimony compounds 12-ethynyl-tetrahydrodibenz[c,f][1,5]azastibocines: Highly efficient new transmetallating agent for organic halides
Extremely efficient and high-speed ethynylation of acyl chlorides, aryl iodides and bromides was demonstrated by palladium-catalyzed cross-couplingreaction of N-t-butyl-Sb-ethynyl-5,6,7,12-tetrahydrodibenz[c,f][1,5]azastibocine under mild conditions. Optimization and generalization of the hypervalent antimony-mediated coupling reaction are presented in detail. Single-crystal X-ray analysis of the N-methyl-1