Questions tagged [grignard-reagent]

For questions about Grignard reagents RMgX (R = alkyl/aryl/vinyl, X = halide): their chemical and physical properties and reactions.

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Why does magnesium prefer to insert into C–Br bonds over C–Cl bonds?

In the formation of a Grignard reagent from a compound possessing both bromine and chlorine, magnesium preferentially inserts into the C–Br bond over the C–Cl bond. For example, the formation of a ...
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1answer
198 views

What are the parameters of protonation of a molecule?

Adding an acid replaces the $\ce{-MgBr+}$ with an $\ce{H+}$. Why does this happen? Is $\ce{H+}$ a better electrophile than $\ce{MgBr+}$? Or, to put it another way, why doesn't $\ce{MgBr}$ stays ...
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702 views

Mechanism for reaction of an allene with the Grignard Reagent(RMgX)

How does the Grignard Reagent($\ce{RMgX}$) react with an allene $\ce{CH_2=C=CH_2}$ and what are the products formed? This is exactly what I tried to do. Any help will be appreciated.
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Why might the yield of my synthesis of triphenylmethanol be so poor?

I performed the classic Grignard reagent formation leading into the preparation and purification of triphenylmethanol using phenylmagnesium bromide as my Grignard, and benzophenone as the reagent for ...
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Reactions of Grignard Reagents with amides

Can Grignard reagents add to amides? It appears from the synthetic pathway shown below that there has been some form of nucleophilic substitution at the carbonyl group. Source: 49th IChO Preparatory ...
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Reactivity of Grignard reagent

I had the following question at an exam: What is the fastest reacting compound towards nucleophilic addition with Grignard reagent? (a) Acyl chloride (b) Aldehyde (c) Ester It is ...
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71 views

A compound that reacts with ethyl magnesium bromide and also decolorizes bromine water

Which of the following compounds reacts with ethyl magnesium bromide and also decolorizes bromine water solution: Is the answer only option (c)?
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76 views

Preparation of 3-ethylpentan-3-ol

Is it possible to use CI3TMS (a carbon with three iodo groups and a trimethylsilyl protecting group) and three equivalents of an ethyl grignard reagent to prepare 3-ethylpentan-3-ol? By deprotecting ...
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42 views

Reaction rate of Mg with aryl halides

I have been thinking of the rate of reaction of aryl bromide and aryl chloride with $\ce{Mg}$ to form Grignard. When considering the electronegativities the carbon in aryl chloride is more ...
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108 views

Is it possible to obtain n-butane by treating halopropane grignard reagent with methanol?

The answer is a,b. My mechanism however doesn't give n-butane when R is propyl. Is this a case of textbook errata? Himanshu Pandey, Advanced Problems In Organic Chemistry, 9th edition ...
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240 views

Steric Factors on reaction with grignard reagent

I was asked to find the products X and Y. For the product X,Here the grignard reagent and even the carbonyl substrate was too sterically hindered to approach the carbonyl center so no reaction would ...