Nucleophilic Vinylic Substitution (S<sub>N</sub>V) of Trisubstituted Monofluoroalkenes for the Synthesis of Stereodefined Trisubstituted Alkenes and Divinyl Ethers
作者:Yuwei Zong、Qiao Ma、Gavin Chit Tsui
DOI:10.1021/acs.orglett.1c02359
日期:2021.8.6
We herein describe a nucleophilic vinylic substitution (SNV) of trisubstituted monofluoroalkenes with excellent stereocontrol (d.r. > 99:1). Starting from (E)-β-monofluoroacrylates, various trisubstituted (E)-alkenes containing O/N/S-substituent groups at the vinylic position can be obtained under simple conditions. Furthermore, (E,E)-divinyl ethers can be generated through dimerization of the monofluoroalkenes
我们在此描述了三取代的单氟烯烃的亲核乙烯基取代 (S N V),具有出色的立体控制 (dr > 99:1)。以( E )-β-单氟丙烯酸酯为原料,在简单的条件下,可以得到在乙烯基位置含有O/N/S-取代基的各种三取代( E )-烯烃。此外,( E,E )-二乙烯基醚可以通过单氟烯烃的二聚作用产生,由反应混合物中的外来水引发。
Palladium-Catalyzed Stereoselective Hydrodefluorination of Tetrasubstituted <i>gem</i>-Difluoroalkenes
作者:Qiao Ma、Caroline Liu、Gavin Chit Tsui
DOI:10.1021/acs.orglett.0c01813
日期:2020.7.2
A highly stereoselective palladium(0)-catalyzed hydrodefluorination (HDF) of tetrasubstituted gem-difluoroalkenes is developed. By usingcatalytic Pd(PPh3)4 (2.5–5 mol %) and hydrosilane Me2PhSiH, various trisubstituted terminal (E)-monofluoroalkenes can be synthesized with excellent E/Z selectivity (>99:1) and good functional group tolerability. The key stereocontrol should be exerted by an ester-directed
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。