摘要
Kinetic isotope effects H/D in electrophilic fluorination of aromatic compounds with NF-reagents were investigated. The small values of k(H)/k(D) (0.86-1.00) are in agreement with the polar reaction mechanism where the Wheland complex decomposition is not the limiting stage. The fluorination of 1,3,5-trideuterobenzene was established by H-1 and F-19 NMR spectroscopy to occur with a 1,2-migration of a hydrogen (deuterium) atom. The analysis of Brown-Stock relationship demonstrated that the activity of NF-reagents exceeded that of many known electrophilic systems including halogenation, but it was essentially less than the activity of elemental fluorine.