Allylmagnesium bromide is a Grignard reagent used for introducing the allyl group.

It is commonly available as a solution in diethyl ether.

It may be synthesized by treatment of magnesium with allyl bromide while maintaining the reaction temperature below 0 °C to suppress formation of hexadiene.

[1] Allyl chloride can also be used in place of the bromide to give allylmagnesium chloride.

[2] These reagents are used to prepare metal allyl complexes.