Magnesium iodide has few commercial applications. The salt is used to prepare several addition compounds with organic solvents, some of which are used in organic synthesis.
Anhydrous magnesium iodide, when reacted with cyclic sulfates of vic-diols, produces the corresponding olefins in excellent yields.
Magnesium iodide is used as reagents and intermediates in pharmaceuticals. It is useful in Baylis-Hillman reactions.
Crystallise it from water (0.8g/mL) by partial evaporation in a desiccator. It is deliquescent and should be stored in the dark. [Ehrlich in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol I p 910 1963.]