Phenyselenium trifluoride, PhSeF3 (PSTF) either oxidatively difluorina
tes or selenofluorinates olefins, depending on their structures. The p
entafluorides PhSeF5 and PhTeF5 appear to be effective difluorinating
reagents, affording 1,2-difluoroalkanes from olefins. (C) 1998 Elsevie
r Science S.A.