通过钯(0)催化的三重多米诺工艺开发了一种高效,高度区域选择性和立体选择性的合成四取代烯烃的方案。它涉及通过双碳钯和通过2-降冰片芳基炔基联芳基/杂芳基与降冰片烯的双碳键合和CH活化形成三个新的CC键。该方法实际上很简单,具有广泛的底物范围,并且可以耐受各种取代基。带有9 H-吡咯并[1,2- a ]吲哚基序的产物显示出令人感兴趣的固态荧光特性,因此形成了一类新的聚集诱导发射(AIE)荧光团。
Alkynes as Linchpins for the Additive Annulation of Biphenyls: Convergent Construction of Functionalized Fused Helicenes
作者:Rana K. Mohamed、Sayantan Mondal、Joseph V. Guerrera、Teresa M. Eaton、Thomas E. Albrecht‐Schmitt、Michael Shatruk、Igor V. Alabugin
DOI:10.1002/anie.201606330
日期:2016.9.19
A new approach to fused helicenes is reported, where varied substituents are readily incorporated in the extended aromatic frame. From the alkynyl precursor, the final helical compounds are obtained under mild conditions in a two‐step process, in which the final C−C bond is formed via a photochemical cyclization/ dehydroiodination sequence. The distortion of the π‐system from planarity leads to unusual
Palladium-Catalyzed Cycloisomerization of 2-Ethynylbiaryls to 9-Methylidene Fluorenes
作者:Hongyu Guo、Sheng Zhang、Xiujuan Feng、Xiaoqiang Yu、Yoshinori Yamamoto、Ming Bao
DOI:10.1021/acs.orglett.2c00534
日期:2022.4.15
presence of weak acid at low temperature to afford 9-methylidene fluorenes in satisfactory to high yields. This new type of cycloisomerization of 2-ethynylbiaryls is operationally simple and scalable and exhibits high functional-group tolerance. Various synthetically useful functional groups, such as halogen atoms, as well as formyl, acetyl, methoxycarbonyl, cyano, and nitro groups, remain intact during
α-Carbonyl Radicals from <i>N</i>-Enoxybenzotriazoles: De Novo Synthesis of 9-Phenanthrols
作者:Quynh H. Nguyen、Tae-Woong Um、Seunghoon Shin
DOI:10.1021/acs.orglett.2c03356
日期:2022.11.18
donors or alcoholic solvents led to α-carbonylradicals. The utility of the α-carbonylradicals was demonstrated in intramolecular tandemcyclization and in the synthesis of 9-phenanthrols and their analogues. The mechanistic experiments suggested that quenching of the reactive benzotriazolyl radical by the alcohol was accompanied by the formation of an α-hydroxy radical that mediated hydrogen atom transfer
A highly modular approach to fused 1,2,3-triazoles has been developed featuring a one-pot procedure combining copper(I) catalyzed azide-alkyne cycloaddition and palladium-catalyzed C-H bond functionalization. A class of structurally unique heterocycles was synthesized in good yields.