[AlphaScent]

In a methylmagnesium bromide reaction with a tosylate, Copper Iodide is used to mediate the reaction.  If someone were to have run out of copper iodide and have copper bromide on hand, could this be used in the reaction.  I am doing the reaction in a polar aprotic solvent so the bromide would be less nucleophilic towards my tosylate.  I think it would be ok, with the difference being in solubility??

[opsomath]

Is this a copper-mediated coupling reaction? It sounds like it may be. What is the nature of the tosylate, is it alkyl, aryl, etc?

If that is the case, it is possible that the CuBr could work although it's not guaranteed.

[AlphaScent]

Yes, copper mediated.  I am doing this for production, so it is a large scale.  It is a waste of time for me to do a small scale trial reaction.  The Copper Iodide will be in tomorrow.  Thanks for your input!