The constitution of a di-Grignard reagent

Abstract

Analyses and dilution studies of the di-Grignard reagent of 4,4′-dibromodiphenyl ether in tetrahydrofuran have shown that its composition is concentration dependent. Molecular-weight determinations by light scattering and isopiestic techniques show that, although dissociation occurs, the reagent is polymeric at great dilutions the molecular shape approximating to a rod-like structure. The solute species approach the composition RMg₃Br₄ which corresponds to the R₂Mg,MgX₂ formula of mono-Grignard reagents.