Questions tagged [carbonyl-compounds]

For questions about compounds containing the carbonyl group, C=O, the carboxylic acid group (-COOH), or its derivatives (anhydrides/esters/amides/acid halides). For questions about complexes involving carbon monoxide as a ligand use [carbonyl-complexes] instead.

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11
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1answer
46k views

What is the mechanism for oxidation of ketones by the Popoff's rule?

Ketones are relatively much harder to oxidise, but they do undergo oxidation reactions at extreme temperatures. Our teacher also told us about Popoff's rule which states that, on oxidation of ...
7
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2answers
910 views

Why does formaldehyde exist primarily as the gem-diol in aqueous solution?

From Wikipedia, Methanediol is the product of the hydration of formaldehyde $\ce{H2C=O}$, and predominates in water solution: the equilibrium constant being about $10^3$ and in a 5% by weight ...
5
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1answer
3k views

Assignment of the IR spectrum of 2,4-pentanedione (acetylacetone)

The IR spectrum is shown here: My assignments so far: The 1728 and 1708 stretches correspond to $\ce{C=O}$ stretches in the keto form - the symmetric/asymmetric stretches respectively. The 3003 ...
4
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1answer
2k views

Carbonyl oxygen as nucleophile

Aldehydes and ketones have electrophilic centres at their carbonyl C, since the carbonyl O polarises the bond and attracts electron density towards itself on account of its high electronegativity. But ...
5
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3answers
435 views

Decarboxylation of cyclohex-1-ene-1,2-dicarboxylic acid by electrolysis method

What is the major product when cyclohex-1-ene-1,2-dicarboxylic acid is electrolysed? My try: I got 2 cases but I am unable to decide which product is major, and need help here.
2
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1answer
341 views

Omission of locants for functional groups in IUPAC names

I'm having a bit of conflict while naming molecules as per IUPAC the nomenclature rules. If we take the following compound for example, IUPAC would say that that correct name is 2-...
1
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1answer
242 views

Acid Catalysed Ring Expansion – Mechanism?

Ring expansion of vinyl cyclobutane - Could someone please help me with a detailed mechanism for the above conversion? It is the acid-catalyzed rearrangement of 4,7,7-trimethylbicyclo[3.2.0]hept-3-...
3
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0answers
49 views

Transformation of an epoxido-carboxylic acid to an aldehyde [duplicate]

So I am battling with the last part of this transformation and was hoping someone could explain this mechanism to me so that I can confirm my answer. Treating an alcohol with a strong hydrohalic ...
-1
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2answers
62 views

Addition of a methyl group to a heterobicyclic ring [closed]

I am battling to understand how this reaction works. It should be a carbonyl addition reaction but I am not 100% sure how to reach each step. Could someone explain the mechanism to me?
1
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0answers
407 views

Acidity of aldehydes and ketones and enolate formation

In most academic courses you'd learn that aldehydes are more acidic (lower $\text{p}K_\text{a}$) than ketones due to the lower electron donating effect of the proton compared to the alkyl group of the ...
4
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1answer
378 views

Assignment of the 13C NMR of 2-heptanone

The 13C NMR of 2-heptanone is given below: I understand the assignments of the carbons labelled 7, 6, 4 and 1. My question is: Why is the shift of environment 5 higher than that of 3, despite being ...
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5answers
3k views

Why can enolizable aldehydes undergo Cannizzaro reactions?

Why does 2-methylpropanal undergo a Cannizzaro reaction even though it has an $\alpha$-hydrogen?
7
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1answer
2k views

Does aldol condensation give different products in different conditions?

I know the mechanism of aldol condensation and general method to determine products in crossed aldol reactions, or reactions between dissimilar molecules. But the following statement in my class notes ...
1
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1answer
878 views

Does the iodoform reaction form hydrogen iodide or water?

I am currently learning about the iodoform reaction, i.e. when CH3COR compounds react with iodine and sodium hydroxide to form iodoform. My course book and Chemguide both says that the reaction is as ...
0
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1answer
87 views

Same set of carboxylate reagents yielding two different products with an alkylide

I recently came across two contrasting products for the same set of reagents - carboxylic acid and alkyllithium, and wish to understand why exactly any difference exists between the two. Reaction 1 ...
6
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1answer
2k views

Are groups other than carbonyl reduced by Clemmensen reduction?

According to my textbook, Clemmensen reduction reduces only aldehydes and ketones to alkanes. But in this question: $\ce{Zn-Hg/HCl}$ has reduced both the ketonic and nitro group. Correct answer given ...
0
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1answer
765 views

How is using Jones reagent different than Potassium dichromate in Sulfuric acid for the oxidation of alcohols?

I was taught at an institution I study in that using $\ce{K2Cr2O7}$ in the presence of $\operatorname{dil}.\ce{H2SO4}$ will oxidise $1^{\circ}$ alcohols to aldehydes, and $2^{\circ}$ alcohols to ...
3
votes
1answer
681 views

Which is the better leaving group in the following Cannizzaro reaction?

In the given mechanism, is it correct to prefer hydrogen as a better leaving group than the formyl group? The negative charge on an sp2 hybridized carbon, with the carbonyl group attached to it, ...
9
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1answer
8k views

Can hydrogen on platinum reduce carboxylic acids and esters?

Can $\ce{H2/Pt}$ reduce carboxylic acids and esters? I am confused about the reducing nature of hydrogen in presence of platinum. In some books, it reduces carboxylic acid and ester while in others, ...
3
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1answer
570 views

I am confused about the stability of carbanion III and IV in the image

I am confused about the stability of carbanion III and IV in the image, I think III is more unstable because of electron donating effect (+R) of -OCH3 group but my book says III is more stable than ...
3
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0answers
864 views

Which enolate of butanone is more stable?

Consider butanone (A) and its two possible enolates B & C. Which of the two enolates will be more stable? B because of the more stable primary carbanion, or C because of more stable enolate (...
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0answers
185 views

pKa of different sites of butanone

From what I can tell, deprotonation of the central hydrogen leads to the more thermodynamically stable product (most substituted double bond. i.e. most stabilization by hyperconjugation). Therefore, ...
12
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2answers
2k views

Regioselective enolate formation

Our professor only told us that A is favored, and B is not getting formed. I thought about the resonance structures and saw a contradiction to that what the prof told us. To be honest I think my ...
5
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1answer
721 views

Why does N-phenylhydroxylamine give Fehling's test?

I have studied that Fehling's test is given by aldehydes and alpha hydroxy ketones. I read in a book that it is also given by phenylhydroxylamine converting it to nitrosobenzene. Does it gives the ...
6
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1answer
3k views

Why is in the reaction of cyclic unsaturated aldehydes with hydrazine and hydrogen peroxide the aldehyde preserved?

Question What is the product of this reaction? The answer given: At first, I thought this was a typical Wolff-Kishner reduction, but then I saw the reagents didn't match up (no $\ce{OH-}$...
5
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1answer
106 views

What is the problem with forming 2,3-dimethylcyclohex-2-en-1-one?

I have suggested a mechanism for the formation of 3-ethyl-2-methylcyclohex-2-en-1-one A but the question says problems would be encountered if a similar route was used to make 2,3-dimethylcyclohex-2-...
5
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3answers
1k views

Which tautomer of hexane-2,4-dione is more stable?

Which tautomer will be more stable? Both 1 and 2 show intramolecular hydrogen bonding and form 6 membered cyclic ring, thus increasing the stability. I think I need to compare the effect of the two ...
5
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1answer
459 views

How to dialkylate a cyclohexene, and convert a carbonyl to an alkene?

I'm trying to design a synthesis of D from C. All I can think of is using $\ce{Me2CuLi}$ to add the methyl group to the alkene. I thought maybe then if isobutyl bromide was in the reaction mixture ...
3
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1answer
5k views

Can all species that undergo aldol reactions also undergo Cannizzaro reactions?

Can all species that undergo aldol reactions also undergo Cannizzaro reactions? Ater all, the nucleophile can always attack the carbonyl group.
2
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1answer
116 views

One-pot synthesis of pyrazole [closed]

I am trying to follow a published paper. It is a one-pot synthesis of pyrazole from a ketone and and acid chloride via a diketone intermediate. Here is the produre from the paper: General Procedure:...
2
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3answers
406 views

Conversion from t-butanol to alkene

How can I accomplish the above conversion? My thoughts: One way of introducing the double bond, would be using the appropriate Grignard Reagent after oxidation of t-butanol (somehow) I think that ...
7
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2answers
14k views

Which will be the most acidic hydrogen in the following organic compounds?

Which will be the most acidic hydrogen in both cases? Please explain. According to me, in the first compound 2 should be most acidic as in both 1 and 2, resonance occurs but 2’s carbon is closer to ...
7
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2answers
2k views

Why does no Robinson Annulation occur after the Michael addition?

Under basic conditions a Michael addition reaction can be used to convert compound A into product C. Explain why no Robinson annulation cyclic product is observed? Compound A Product C ...
8
votes
2answers
306 views

Is 2-oxobicyclo[2.2.1]heptan-1-ide resonance stabilized?

Is the following compound resonance stabilized? I think its not resonance stabilized because the p-orbital of carbanion and pure p-orbital of carbonyl carbon are not in same plane. So they can't ...
10
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2answers
1k views

Prediction of products in reaction of dicarbonyl with alpha-haloketone

Following is the question that was asked in my exam. a,b,c,d are the various options, one of which is the answer. I am familiar with the Reformatsky reaction, Aldol condensation, Knoevenagel's ...
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1answer
1k views

Reaction of a vicinal diol with acetone

I have the first part correct; however, I can't seem to understand what the 2nd part's answer is. I realize the water leaves, but then what?
0
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1answer
2k views

Why is acetyl cyanide not obtained from acetyl chloride?

Why doesn't acetyl chloride or any other aliphatic acyl chloride react with cyanide ions and undergo nucleophilic addition elimination to form aliphatic acyl cyanide, even though this reaction occurs ...
5
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2answers
1k views

What are the products of the haloform reaction of acetylacetone?

I searched a lot to find the products of the haloform reaction of acetylacetone (pentane-2,4-dione), but I didn't find any results. What are the products of the haloform reaction of acetylacetone?
8
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1answer
4k 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 ...
6
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1answer
13k views

IUPAC name for citric acid

I wonder what the name is of the following structure is: I think it's something like 3-hyrodxypentanoic diacid However, I wasn't able to find how to name a side chain if it contains a $\ce{COOH}$ ...
5
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1answer
1k views

How is phosphoryl chloride attaching an aldehyde to benzene?

This reaction was part of an organic scheme I was doing: I thought that $\ce{POCl3}$ just converts the OH group into Cl, but looking at the chemical formula for A, I noticed that A has an extra ...
-2
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1answer
565 views

Rate of formation of hydrate in a carbonyl compound [closed]

When water in presence of any acid is added to a carbonyl compound, it leads to the formation of its hydrate. But how do we determine the rate of reaction? Is it done by checking the amount of partial ...
1
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0answers
94 views

How to determine the pH range at which maximum hydrate is present?

Question: Find the $\mathrm{pH}$ range at which maximum hydrate is present in a solution of oxaloacetic acid (given $\mathrm{pK_a}$ of $\ce{-COOH}$ in the left is $=2.2$ and on the right is $=3.98$)...
15
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2answers
6k views

Is tropone aromatic?

Looking at resonance structure 1a, it doesn't seem that tropone is aromatic. However, the resonance structure 1b with $\ce{C+-O-}$ satisfies Hückel's rule for aromaticity. Is it correct to say that ...
3
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2answers
3k views

Does acetamide respond positively to iodoform test?

This answer explains why acetic acid does not give a positive iodoform test. Does acetamide respond positively to the test?
1
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1answer
718 views

Base used in Claisen Condensation

Here's what I read about which base to use in Claisen Condensation reaction (two esters or ester + carbonyl compound forming a beta keto-ester or beta-diketone): The base used must not interfere ...
4
votes
1answer
8k views

Hydrolysis of cyclic acetal

What happens to 1,5-dimethyl-6,8-dioxabicyclo[3.2.1]octane when it is hydrolyzed under acidic conditions? I know that under acidic conditions the first thing to likely happen is protonation. Does it ...
5
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3answers
1k views

Do the π-electrons from the C=O bond in tropone contribute to Hückel 's rule?

This is a continuation of Is tropone aromatic? I'm looking at the resonance form that does have the carbonyl double-bond, 1a. Can this resonance structure also be considered aromatic? Would the ...
7
votes
2answers
617 views

What is the driving force for imine formation?

I know this that when a primary amine is reacted with a carbonyl compound, an imine is formed: I'm wondering why the position of this equilibrium lies to the product side / right-hand side. Why is ...
4
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1answer
1k views

Byproducts of LiAlH4 reduction of amides

I know that $\ce{LiAlH4}$ is able to reduce amides into amines, e.g. benzamide into benzylamine. However, I am unsure what other by-products are formed as a result. $$\ce{LiAlH4 + C6H5CONH2 -> ...