All Questions
Tagged with reactivity carbonyl-compounds
23
questions
28
votes
3
answers
60k
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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 ...
- 44.3k
22
votes
4
answers
8k
views
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 ...
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18
votes
2
answers
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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 ...
- 6,233
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 ...
- 2,106
13
votes
1
answer
8k
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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 ...
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13
votes
1
answer
672
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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 ...
- 139
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 ...
- 1,782
6
votes
2
answers
1k
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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 }$
$\...
- 3,071
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 ...
- 149
6
votes
0
answers
291
views
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 ...
- 454
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 ...
- 19k
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 ...
user92687
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{...
- 1,817
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 ...
- 173
2
votes
1
answer
2k
views
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 ...
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