Stereoselective formation of alkenyl halides via magnesium halide promoted ring opening of bis-activated cyclopropenes.

In the presence of stoichiometric magnesium halides, a range of bis-activated cyclopropenes undergo highly stereoselective ring-opening reactions to produce multisubstituted alkenyl halides. More highly functionalized compounds may be obtained by trapping of the magnesium enolate intermediates in situ.