Controlling Ni redox states by dynamic ligand exchange for electroreductive Csp3–Csp2 coupling
作者:Taylor B. Hamby、Matthew J. LaLama、Christo S. Sevov
DOI:10.1126/science.abo0039
日期:2022.4.22
Cross-electrophile coupling (XEC) reactions of aryl and alkyl electrophiles are appealing but limited to specific substrate classes. Here, we report electroreductive XEC of previously incompatible electrophiles including tertiary alkyl bromides, aryl chlorides, and aryl/vinyl triflates. Reactions rely on the merger of an electrochemically active complex that selectively reacts with alkyl bromides through
芳基和烷基亲电试剂的交叉亲电偶联 (XEC) 反应很有吸引力,但仅限于特定的底物类别。在这里,我们报告了以前不相容的亲电子试剂的电还原 XEC,包括叔烷基溴、芳基氯和芳基/乙烯基三氟甲磺酸酯。反应依赖于通过 1e – 过程选择性与烷基溴反应的电化学活性络合物和通过 2e – 过程选择性与芳基亲电子试剂反应的电化学非活性 Ni 0 (膦) 络合物的合并。获取 Ni 0 (膦)中间体对于该策略至关重要,但通常具有挑战性。我们发现了一条以前未知的途径,通过一系列精心设计的配体交换反应,在温和的电位下电化学生成这些关键复合物。这种温和的方法适用于一系列底物的烷基化,包括天然产物和药物。
Ni-complex-catalysed addition polymerisation of 2-phenyl-1-methylenecylopropane to afford a polymer with cyclopropylidene groupsElectronic supplementary information (ESI) available: full details of the experimental procedures, DSC and TG profile of I. See http://www.rsc.org/suppdata/cc/b1/b111697e/
作者:Daisuke Takeuchi、Kohtaro Osakada
DOI:10.1039/b111697e
日期:2002.3.7
π-Allyl-nickel complexes initiated addition polymerisation of 2-phenyl-1-methylenecyclopropane to give a polymer with three-membered rings; the formed polymer showed a high Tg and negligible thermal decomposition up to 300 °C.
Bromine Radical-Mediated Sequential Radical Rearrangement and Addition Reaction of Alkylidenecyclopropanes
作者:Takashi Kippo、Kanako Hamaoka、Ilhyong Ryu
DOI:10.1021/ja311821h
日期:2013.1.16
Bromine radical-mediated cyclopropylcarbinyl-homoallyl rearrangement of alkylidenecyclopropanes was effectively accomplished by C-C bond formation with allylic bromides, which led to the syntheses of 2-bromo-1,6-dienes. A three-component coupling reaction comprising alkylidenecyclopropanes, allylic bromides, and carbon monoxide also proceeded well to give 2-bromo-1,7-dien-5-ones in good yield.
溴自由基介导的亚烷基环丙烷的环丙基羰基-高烯丙基重排通过与烯丙基溴形成 CC 键有效地完成,从而合成 2-溴-1,6-二烯。包括亚烷基环丙烷、烯丙基溴和一氧化碳的三组分偶联反应也进行得很好,以良好的收率得到2-溴-1,7-二烯-5-酮。
Nickel‐Catalyzed C−I‐Selective C(<i>sp</i><sup>2</sup>)−C(<i>sp</i><sup>3</sup>) Cross‐Electrophile Coupling of Bromo(iodo)arenes with Alkyl Bromides
作者:Xiaoyuan Ying、Yuxi Li、Luyang Li、Chao Li
DOI:10.1002/anie.202304177
日期:2023.6.26
bromo(iodo)arenes with 3°, 2°, and 1°alkyl bromides is reported. This mild XEC displays a broad scope with demonstrated functional group tolerance and finds use in the streamlined preparation of synthetically challenging bioactive compounds. Given the prevalence of its buildingblocks and the substrate generality, this discovery will likely inspire numerous applications.
Pd-Catalyzed Ring-Opening Copolymerization of 2-Aryl-1-methylenecyclopropanes with CO to Afford Polyketones via Alternating Insertion of the Two Monomers and C−C Bond Activation of the Three-Membered Ring
作者:Sunwook Kim、Daisuke Takeuchi、Kohtaro Osakada
DOI:10.1021/ja017460s
日期:2002.2.1
Pd-bpy complexes catalyze the ring-opening copolymerization of 2-aryl-1-methylenecyclopropanes with CO, affording the new polyketones composed of ring-opened structural units only. Kinetic and isotope-labeling studies revealed the mechanism of the reaction, which involves 1,2-insertion of the cyclic monomer followed by beta-alkyl elimination of the three-membered ring of the polymer chain.