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    Hi.

    I'm trying to understand how this mechanism works. Can someone describe it verbally for me?



    Thanks
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    I think you've drawn it wrong (your first set of arrows don't make sense and the middle structure has an extra charge).

    The magnesium attacks the C-Br bond, splitting it homolytically to form R. and Mg+.Br- then you get radical termination to form the Grignard reagent.
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    (Original post by 'bob')
    Hi.

    I'm trying to understand how this mechanism works. Can someone describe it verbally for me?



    Thanks
    it is essentially oxidative addition. ie Mg ---> Mg2+, and the organic reactant has been "reduced" becoming essentially a source of carbanion.

    Different mechanism have been drawn for the formation of grignard. you might argue it is radical, but i'd personally draw them like i do for the rest of organometallic mechanisms.
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    (Original post by shengoc)
    it is essentially oxidative addition. ie Mg ---> Mg2+, and the organic reactant has been "reduced" becoming essentially a source of carbanion.

    Different mechanism have been drawn for the formation of grignard. you might argue it is radical, but i'd personally draw them like i do for the rest of organometallic mechanisms.
    Thanks. After some reading its apparent that there isn't a completely accurate mechanism yet but it is basically oxidative addition like you said. I just drew this in the end since it's way simpler and explains it just as well. The whole free radical thing was a bit iffy.

 
 
 
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