FLUOROSELENENYLATION OF ACETYLENES WITH XENON DIFLUORIDE-DIORGANYL DISELENIDES AND XENON DIFLUORIDE-PHENYLSELENO (TRIALKYL)SILANES

A new, efficient method of fluoroselenenylation of terminal, and open- chain symmetric and unsymmetric disubstituted acetylenes and cycloalky nes, gives vicinal (E)-fluoroalkenyl selenides in moderate to high yie lds by addition of selenenyl fluoride equivalents. These are formed in situ from xenon difluoride and diaryl, dibenzyl or primary and second ary dialkyl diselenides. Alternatively, the benzeneselenenyl fluoride equivalent is formed by treatment of more reactive phenylselenotrialky lsilanes with xenon difluoride. The regiochemistry of the addition is strongly dependent on the steric effects of substituents bonded to the acetylene.