Novel Stereoselective Synthesis of (<i>Z</i>)-α,β-Unsaturated Esters by Hydrostannylation-Stille Tandem Reaction of Alkynyl Esters with Aryl Iodides
作者:Jianying Li、Yan Yu、Mingzhu Cheng、Mingzhong Cai
DOI:10.3184/174751911x13192956847054
日期:2011.11
( Z)-α,β-Unsaturated esters can be stereoselectively synthesised in one pot under mild conditions and in good yields, by the hydrostannylation of alkynyl esters followed by Stille cross-coupling with aryl iodides.
Rhodium(I)-Catalyzed Defluorinative Coupling of Boronic Acids with Monofluoroalkenes
作者:Yuwei Zong、Yihan Tang、Gavin Chit Tsui
DOI:10.1021/acs.orglett.2c02294
日期:2022.9.9
We herein describe a highly selective Rh(I)-catalyzed defluorinative coupling of boronic acids with (E)-β-monofluoroacrylates. In contrast to previous methods, the trisubstituted (Z)-alkene products were obtained in excellent dr with an inversion of double bond geometry. Experimental and computational studies established that Rh(I)-facilitated β-F elimination is favored over competing β-H elimination
我们在此描述了硼酸与 ( E )-β-单氟丙烯酸酯的高选择性 Rh(I) 催化的脱氟偶联。与以前的方法相比,三取代的 ( Z )-烯烃产物以优异的 dr 获得,双键几何形状反转。实验和计算研究表明,Rh(I) 促进的 β-F 消除优于竞争性 β-H 消除和原脱金属。
Palladium-Catalyzed Hydroarylation of Alkynes with Arenediazonium Salts
The palladium-catalyzed hydroarylation of arenediazonium tetrafluoroborates with alkynes in the presence of triphenylsilane affords stereoselectively hydroarylation products in moderate to high yields. The reaction tolerates a variety of substituents including keto, ester, cyano, and nitro groups and can be performed as a one-pot procedure generating the arenediazonium salt in situ. With ethyl phenylpropynoate as the starting alkyne, the hydroarylation affords ethyl (2)-2-arylcinnamates stereo- and regioselectively.
Palladium-Catalyzed Regio- and Stereoselective Hydrosilylation of Electron-Deficient Alkynes
Highly regio- and stereoselective hydrosilylation applicable to a broad range of electron-deficient alkynes has been established using palladium catalysis. The synthetic utility of the method has been demonstrated by further transformations of α-silylalkenes, particularly Hiyama coupling and stereoinverting iododesilylation followed by Suzuki–Miyaura coupling, which enables stereodivergent syntheses