Selective and efficient direct fluorination of polycyclic aromatic hydrocarbons using 1-fluoro-4-hydroxy-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate)
A new N-F fluorinating reagent 1-fluoro-4-hydroxy-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) (Accufluor NFTh) was effectively used for selective fluorination of polycyclic aromatics. Naphthalene was site-selectively fluorinated to 1-fluoronaphthalene, phenanthrene to 9-fluorophenanthrene, and pyrene to 1-fluoropyrene. In a series of substituted naphthalenes the regioselectivity and effectiveness of fluorination depended on the position and the nature of the substituents.
Pyrolysis of cyclobutanes from styrenes, acrylonitrile and methyl acrylate and polyfluoroolefines
The 2 + 2 cycloadduct of styrene and TFE (1) ring-expands and eliminates HF like a butadiene adduct to give 2,3-difluoronaphthalene (3).Cyclobutane 1 also cleaves to styrene and 1,1-difluorostyrene.Titania and other solid-acids accelerate the ring-expansi