Tetrafluoroethylation of Electron-Rich Alkenyl Iodides Enabled by in situ Generation of Solvent-Stabilized "Ligandless" CuCF2CF2H

Identifier:  imarina:9369108

Handle: https://hdl.handle.net/20.500.11797/imarina9369108

Authors:  Segovia, Cristina M; Porto, Luana L T N; Casasus, Paula; Bascuas, Isabel; Ahmad, Amena; Mestre, Jordi; Bernus, Miguel; Castillon, Sergio; Baker, R Tom; Boutureira, Omar

Abstract:
In this study, we have developed a metal-mediated synthetic method for incorporating the 1,1,2,2-tetrafluoroethyl (CF2CF2H) motif into unactivated, electron-rich alkenyl iodides using cross-coupling reactions. We discovered that the stable Cu(CF2CF2H)(PPh2Me)(3) complex, while unreactive with these substrates, serves as a P-ligated reservoir for the formation of solvent-stabilized "ligandless" and reactive CuCF2CF2H species. This transformation occurs upon addition of CuBr, which partially scavenges the P-ligand in the form of CuBr(PPh2Me)(3). The resulting in situ generated solvent stabilized "ligandless" system significantly enhances the reactivity of the complex, particularly towards challenging electron-rich substrates. This advancement enables the synthesis of HCF2CF2-glycals, as well as nucleosides/nucleobases and arenes.