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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What is the driving force of Bartoli indole synthesis?
The Bartoli indole synthesis mechanism begins with a series of attacks on the nitroarene regent by the Grignard reagents. But the atom $\ce{O}$ in $\ce{-NO2}$ should be negative, and Grignard reagent ...
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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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How many equivalents of Grignard reagent does a nitrile group consume?
I was looking at reactions of grignard reagent with certain kinds of compounds and came across it's reaction with nitrile group:
What I was wondering is what if we don't react the Imine formed after (...
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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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Grignard with nitrile: why is the imine protonated twice?
Steps 2 and 3 in the picture show the imine being protonated twice to form the iminium ion in step 4. I'm a little confused as to why the second protonation occurs; does the imine after step 2 still ...
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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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Why doesnt Grignard reagent precipitate in ether?
I read that Grignard reagents are stabilised in ether by the coordinate bond formation, but according to the Schlenk equilibrium, RMgX is in equilibrium with MgX2 and R2Mg. Here MgX2 is ionic and thus ...
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Does di(n-propyl)ether support Grignard reactions?
It is known that diethyl and dibutyl ethers are good solvents for Grignards, it has been also found that diisopropyl ether does not work. I have never seen dipropyl being discussed.
Edit: For clarity, ...
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Why doesn't an acid-base reaction occur in basic amide hydrolysis instead of nucleophilic acyl substitution?
In the reaction of Grignard reagent with a primary and secondary amide, nucleophilic acyl substiution doesn't happen. The reason given is that R- is a strong base as well as strong nucleophile, an ...
user121185
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Would magnesium react with acyl halides to form a variant of grignard reagent just like alkyl and aryl halides?
We were having a chemistry class in our school and we were discussing the answer to some question related to acyl halides when this popped up. Our teacher mused that it may be possible but he hadn't ...
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Grignard Reagent Facilitates Epoxide Opening
I have read from my textbook, that the opening of an epoxide ring with a strong nucleophile like a Grignard reagent, takes place from a less substituted side, with a higher SN2 character.
The acidic ...
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Reaction Of Grignard's Reagent with Acyl Chloride
My organic chemistry book says that Grignard reagents react with acyl chloride just as hydride reagents.
Further in an in-text question
now using above theory, my answer is
But Answer in Solution ...
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Why ester reaction with one equivalent of Grignard reagent produces ketone?
While reviewing my old materials before an external exam which also covers these topic I stopped by one of the reactions - Grignard w/esters:
From what I remember, and what my notes are also telling ...
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Is it possible to produce an epoxide from 2-bromoacetyl bromide using methyl magnesium bromide
This is also one of the questions from practice papers for the JEE , asks for 2 step reaction for epoxidation of ketene
For product A , π complex is generated on c-c bond since carbon labelled 1 is ...
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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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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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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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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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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 ...
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