Copper Causes Regiospecific Formation of C4F8-Containing Six-Membered Rings and their Defluorination/Aromatization to C4F4-Containing Rings in Triphenylene/1,4-C4F8I2 Reactions

摘要

The presence of Cu in reactions of triphenylene (TRPH) and 1,4-C4F8I2 at 360 degrees C led to regiospecific substitution of TRPH ortho C(beta) atoms to form C4F8-containing rings, completely suppressing substitution on C(alpha) atoms. In addition, Cu caused selective reductive-defluorination/aromatization (RD/A) to form C4F4-containing aromatic rings. Without Cu, the reactions of TRPH and 1,4-C4F8I2 were not regiospecific and no RD/A was observed. These results, supported by DFT calculations, are the first examples of Cu-promoted 1) regiospecific perfluoroannulation, 2) preparative C-F activation, and 3) RD/A. HPLC-purified products were characterized by X-ray diffraction, low-temperature PES, and H-1/F-19 NMR.