[zhuguang21]

  I have a project of preparation2-methylpropane-magnesium chloride(t-butyl magnesium chloride) ,it usually way synthesis from 1-chloro-2-methylpropane and magnesium,I do some experiment,have some problem with it does't initiated,so I added to the reaction a few  iodine ,to a same result.
  So I think where was wrong? How water in ether,tert-butylchloride?the analysis  resulted all  0.04%.the water as negative.Initiation? Grignard reaction initiate usually way by added a few iodine ,or 1,2-dibromoethane,or heat with warm air.I all do it before,I try reflux a long time, same resulted.
  where is wrong?

[OC pro]

Your starting material is not very reactive since it is sterically hindered. You should try THF or even 1,4-Dioxane as solvent. Add the t-butyl chloride to a refluxing THF/Mg mixture. I think you have to stir under reflux for at least one or two hours until the Grignard reagent has been formed. Yield for the formation of Grignard reagent will not be higher than 70%.

[zhuguang21]

thanks,I try again your method,the magnesium will be clear not less than stir reflux 4 hours with THF.