All Questions
Tagged with reactivity carbonyl-compounds
23
questions
2
votes
0
answers
43
views
Comparing reactivity of benzaldehyde and 2-butanone for nucleophilic addition
I was taught that, in general, aldehydes are more reactive than ketones because of two reasons: 1) less steric hindrance, and 2) alkyl groups on both sides of carbonyl group in ketones have a stronger ...
2
votes
1
answer
136
views
Why does the reaction of Brady's reagent and cyclohexanone not also form an enamine-type product?
In this reaction in a Khan academy video, cyclohexanone reacts with Brady's reagent to form hydrazone product.
My question is why doea Brady's reagent + cyclohexanone not also form an enamine product ...
3
votes
1
answer
886
views
Reactivity of Benzaldehyde vs Acetaldehyde and Benzoic acid vs Acetic acid
I was trying to compare the reactivity between acetaldehyde and benzaldehyde. After some googling, I found out that benzaldehyde is less reactive than acetaldehyde because the benzene ring can ...
3
votes
1
answer
240
views
The dependency on electron density in the reactivity order of electrophilic and nucleophilic additions
It is well-known that for electrophilic addition across an alkene, the reactivity increases when intermediate carbocation is more stable (eg. addition of $\ce{HBr}$ or acid-catalyzed addition of $\ce{...
6
votes
0
answers
291
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Reactivity order of DIBAL-H and diborane with esters and acids
I have been taught in class that
DIBAL-H is more reactive towards esters than carboxylic acids while opposite is true for diborane.
Also DIBAL-H mentioned is taken under low temperatures (−78 °C).
I ...
2
votes
1
answer
437
views
Reaction of unsaturated lactone and alcohol
Image source
I found this equation to turn this compound into an ketoester but I am unsure of the reaction mechanism.
I postulate that the alcohol attacks the carboxyl carbon, the O becomes formally ...
6
votes
2
answers
1k
views
Reaction of glucose acetal with acetic anhydride
The following problem was asked in JEE Mains 2020 (Sept 2, Shift 1),
Consider the following reactions:
$\ce{ (i) Glucose + ROH ->[dry HCl] Acetal ->[$x$ eq. of (CH3CO)2O] acetyl derivative }$
$\...
1
vote
1
answer
111
views
How to activate polystyrene with carboxyl group?
Is there a simple (that is one that requires few and not very exotic reagents) chemical reaction to "activate" or "functionalize" the polystyrene of a simple microtitre plate?
In ...
2
votes
0
answers
55
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Reactivity comparison between benzaldehyde and acetaldehyde [duplicate]
One of my teacher says that $\ce{Ph-CHO}$ is more reactive than $\ce{CH3-CHO}$ in performing nucleophillic addition reaction because $\ce{—Ph}$ is planar and thus offers less steric hindrance as ...
4
votes
1
answer
3k
views
Beckmann rearrangement v/s dehydration of Oximes
In the above question, A is an oxime, which is then reacted with phosphorus pentoxide. Now, phosphorus pentoxide is both a dehydrating reagent and a reagent used for Beckmenn rearrangement, but which ...
2
votes
1
answer
2k
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Priority order of attack of grignard reagents on functional groups
Recently I was solving carbonyl compounds and I came across this. Is there some priority order, or logic behind why alcohol reacts first with Grignard reagent and then ketone. Whereas ester could've ...
13
votes
1
answer
672
views
What are the properties of COₓ where x ≥ 3?
$\ce{CO_x}$ are part of the oxocarbon molecule class. Commonly known are $\ce{CO}$ and $\ce{CO2}.$ However, there are molecules in which $x$ is equal to or larger than $3.$ Those molecules are barely ...
14
votes
1
answer
2k
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Ambiguous nature of aldehydic group in glucose
In aqueous solution, α-anomer and β-anomer of glucose
remain in equilibrium with each other along with a small amount of
glucose in open chain form ($0.02~\%$). The open chain form in ...
2
votes
0
answers
456
views
Ketal formation of ethyl acetoacetate
Why does the ketone carbonyl group react in preference to the ester carbonyl?
Is it something to do with the resonance occurring into the ester carbonyl from the oxygen? but how does this make the ...
11
votes
1
answer
4k
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Why are beta-ketoacids better at decarboxylation than gamma or delta?
My book claims that beta-ketoacids and beta-dicarboxylic acids are better at decarboxylating than their gamma and delta counterparts. Why is that?
I would assume that since gamma and delta keto-acids ...
2
votes
1
answer
1k
views
What is more reactive towards a cyanohydrin formation an aldehyde or an Ketone?
Which is more reactive—aldehydes or ketones—towards the nucleophilic addition by cyanide to form cyanohydrins?
6
votes
1
answer
278
views
Electrophilicities of carboxylic acid derivatives
I would like to ask about the rate of hydrolysis for 4-hydroxyphenyl acetate (A), N-(4-hydroxyphenyl)acetamide (B), 4-hydroxyphenyl chloroacetate (C), and methyl 4-hydroxybenzoate (D). I know that ...
13
votes
1
answer
8k
views
Does an acetal give a positive Tollens test?
In Organic Chemistry (Wade) there is a question:
Which of the following compounds would give a positive Tollens' test? (Remember that the Tollens' test involves mild basic aqueous conditions.)
The ...
5
votes
1
answer
3k
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Acid chlorides and reduction by hydrogenation
An acid chloride being reduced through catalytic hydrogenation is an "unobserved" event in the context of our class, according to my professor. Nonetheless, we are expected to predict that the ...
28
votes
3
answers
60k
views
Rationalising the order of reactivity of carbonyl compounds towards nucleophiles
This is immediately following ron's answer from Why is a ketone more nucleophilic than an ester?
One of the most simplest questions you can ask, how can you rationalise the order of reactivity ...
18
votes
2
answers
26k
views
Why is a ketone more nucleophilic than an ester?
I guess the ester is a weaker nucleophile because it does have an additional oxygen atom, unlike the ketone, that is pulling electrons from the C-O double bond towards the carbon atom (this happens ...
2
votes
0
answers
290
views
Primary amine versus phosphoramidate reactivity with succinate esters
I have posted two reactions below. The top reaction is well known and occurs readily and near quantitatively (e.g. in protein modification), while the bottom reaction to my knowledge does not exist in ...
22
votes
4
answers
8k
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Why do Organolithium or Grignard reagents act as nucleophiles and not as bases with aldehydes and ketones
I've read entire Chapter 14: Organometallic Compounds of Francis Carey's "Organic Chemistry" but I still didn't get an answer to my question.
Quote from the book:
Because of their basicity ...