Answers are grounded in this paper and cite their sources.
β-Oxido phosphonium ylides, generated in situ from aldehydes and Wittig reagents [alkylidene(triphenyl)phosphoranes, other than ethylidene(triphenyl)phosphorane], react readily with electrophilic halogen sources to form predominantly or exclusively E -bromo- or iodosubstituted alkenes. The stereochemical outcome on halogenation is remarkably sensitive to alkylidene size [ethylidene(triphenyl)phosphorane is highly Z -selective].
No takes yet. Share an insight, caveat, or question.
Hodgson et al. (2008) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: