Fluorination Triggers Fluoroalkylation: Nucleophilic Perfluoro‐
tert
‐butylation with 1,1‐Dibromo‐2,2‐bis(trifluoromethyl)ethylene (DBBF) and CsF
摘要:
AbstractPerfluoro‐tert‐butylation reaction has long remained a challenging task. We now report the use of 1,1‐dibromo‐2,2‐bis(trifluoromethyl)ethylene (DBBF) as a practical reagent for perfluoro‐tert‐butylation reactions for the first time. Through a consecutive triple‐fluorination process with DBBF and CsF, the (CF3)3C− species can be liberated and observed, which is able to serve as a robust nucleophilic perfluoro‐tert‐butylating agent for various electrophiles. The power of this synthetic protocol is evidenced by the efficient synthesis of structurally diverse perfluoro‐tert‐butylated molecules. Multiple applications demonstrate the practicability of this method, as well as the superiority of perfluoro‐tert‐butylated compounds as sensitive probes. The perfluoro‐tert‐butylated product was successfully applied in 1H‐ and 19F‐magnetic resonance imaging (MRI) experiment with an ultra‐low field (ULF) MRI system.
hydrocarbon counterpart, perfluoro-2-(trifluoromethyl)propene is a highly reactive compound. It participates in both heterolytic and homolytic reactions. It readily reacts with nucleophiles and sluggishly with electrophiles. It reacts as well with common organic solvents, such as dimethylformamide, ethanol and others. In this communication, we describe its reactions with trifluoromethylthiocopper, sulfur
Regioselective Aromatic Perfluoro-<i>tert</i>-butylation Using Perfluoro-<i>tert</i>-butyl Phenyl Sulfone and Arynes
作者:Zhiqiang Wei、Lixian Wen、Kaidi Zhu、Qian Wang、Yanchuan Zhao、Jinbo Hu
DOI:10.1021/jacs.2c10479
日期:2022.12.7
synthetic protocol to realize aromatic perfluoro-tert-butylation. The key to the success is the identification of PFtB phenyl sulfone as a new source of PFtB anion, which reacts with arynes in a highly regioselective manner to afford perfluoro-tert-butylated arenes in high yields. The application of the method is demonstrated by the preparation of sensitive 19F-labeled NMRprobes with an extraordinary resolving