salts has rendered the products easily isolable, which greatly improved the synthetic practicality of the monodefluoroborylation reaction. Stoichiometric experiments indicate that the fate of the regioselectivity depends on the mode of β-fluorine elimination, which depends on the substrate. Further transformation of the boryl group has allowed facile preparation of fluoroalkene derivatives as exemplified
Trifluorovinylzinc is a common synthetic intermediate for trifluorovinyl derivatives, including α,β,β-trifluorostyrenes and hexafluorobutadiene. Here, we report a novel synthetic approach for the formation of trifluorovinylzinc chloride via a C–F bond activation of tetrafluoroethylene (TFE), which is an industrially cost-effective bulk feedstock with a negligible GWP. The present system provides a
activation of fluorinatedalkenes and arenes was developed. In this Pd-catalyzed Suzuki–Miyaura-type cross-coupling reaction, neither a base for enhancing the reactivity of the organoboron reagents nor a Lewis acid for promoting C–F bond activation was required. A fluoropalladium intermediate played an essential role in this reaction. In addition, a Ni(NHC) catalyst was efficient for C–C coupling through
Organofluorine compounds are widely used in all aspects of the chemical industry. Although tetrafluoroethylene (TFE) is an example of an economical bulk organofluorine feedstock, the use of TFE is mostly limited to the production of poly(tetrafluoroethylene) and copolymers with other alkenes. Furthermore, no catalytic transformation of TFE that involves carbon-fluorine bond activation has been reported
Synthesis of Trifluorostyrene Derivatives by Palladium-Catalyzed Cross-Coupling of Lithium Trimethoxy(trifluorovinyl)borate with Aryl Bromides
作者:Sasa Duric、Bernd M. Schmidt、Nina M. Ninnemann、Dieter Lentz、C. Christoph Tzschucke
DOI:10.1002/chem.201103067
日期:2012.1.9
Fluor‐ing it: The stable, crystalline trimethoxy(trifluorovinyl)borate is a convenient reagent for efficiently displacing a bromineatom with a trifluorovinyl group (see scheme). This Suzuki coupling reaction significantly simplifies the route to trifluorostyrenes, which might be interesting compounds for materials science or medicinal chemistry.