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Topic: grignard reaction  (Read 5124 times)

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Offline alexanderdundua

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grignard reaction
« on: December 09, 2007, 05:36:57 AM »
hey,
I have a question
is the following reaction possible?
C6H5Br+BrMgCCH = C6H5CCH+MgBr2

Offline Yarr

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Re: grignard reaction
« Reply #1 on: December 09, 2007, 06:37:02 AM »
Your alkynyl Grignard reagent is expected to react with itself.

Offline alexanderdundua

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Re: grignard reaction
« Reply #2 on: December 09, 2007, 07:06:44 AM »
no, it will not react with itself. BrMgCCH is quite stabile reagent. some chemical companies provide it as solutions in some organic solvents.
« Last Edit: December 09, 2007, 07:43:07 AM by alexanderdundua »

Offline agrobert

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Re: grignard reaction
« Reply #3 on: December 09, 2007, 02:21:20 PM »
Can you propose a reasonable mechanism?
In the realm of scientific observation, luck is only granted to those who are prepared. -Louis Pasteur

Offline OldThrashbarg

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Re: grignard reaction
« Reply #4 on: December 10, 2007, 12:45:13 PM »
Grignard aside, can you have nucleophilic aromatic substitution without any strong electron withdrawing groups?

Offline PAY

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Re: grignard reaction
« Reply #5 on: December 12, 2007, 11:48:37 AM »
Your alkynyl Grignard reagent is expected to react with itself.
This reagent must react with itself anyway! For avoiding this events needs to protect terminal triple bond with Me3Si- or other protective group. Then? this reaction provide coupling product. Especially, if you'll provide this reaction in Kumada conditions(Pd-catalysis).

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