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18 votes
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Why are lactones more acidic than esters?

Overview The only interesting thing about lactones is that if the ring size is relatively small, they necessarily adopt the (E) conformation. Therefore, the question essentially boils down to: for a ...
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16 votes

Why do esters actually smell?

Dissenter is correct about aromatic compounds and that the basic requirement for a compound to be detected by smell is for it to be volatile enough to reach the nose. This is why things like dry salt ...
15 votes
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What is the name origin of ester?

The term "Essigäther" is actually the German name for ethyl acetate i.e Essig = "vinegar" + Äther = "ether". "vinegar" becomes acetic, hence ethyl acetate ...
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11 votes

Is it possible to oxidize ether to ester?

Yes, it is possible. One reagent to do so is acidic bromate salts. This paper discusses a number of optimizations and characterizations of the bromate-powered ether oxidation reaction. $$\ce{R-CH2-...
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11 votes
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Mechanism for formation of amide by reaction of amine with ester

Surely the negatively charged oxygen would protonate before the other oxygen would. Most of the time, but not all of the time. The amine group is more basic than the "alcohol group" that must ...
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10 votes

Why are peroxides unstable but disulfide bridges considered stable? Why are esters stable but thiolesters are unstable?

Some hard data: bond enthalpies (in $\pu{kJ mol-1}$) $$\begin{array}{c|c|c|c} \text{Bond} & \text{Enthalpy} & \text{Bond} & \text{Enthalpy} \\ \hline \ce{C-C} & 350 & \ce{Si-...
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10 votes
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On the use of hexane in the organic reduction by DIBAL-H

Unlike other reducing metal hydrides (e.g., $\ce{NaBH4}$ and $\ce{LiAlH4}$), diisobutylaluminum hydride (DIBAL-H) is a liquid at room temperature and dissolve in many hydrocarbons such as toluene and ...
9 votes

Choice of base for malonic ester synthesis

Understanding how this reaction is actually performed in the lab is key to answering your question. Typically in the malonic ester synthesis, a full equivalent (or 2 equivalents if you are carrying ...
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9 votes
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Why do esters actually smell?

The term aromaticity originated with the discovery of unusually stable hydrocarbons that also happened to have strong smells. Many hydrocarbons smell, but not all are aromatic. Nowadays, a compound ...
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9 votes
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Unusual hydrolysis of methyl 2,4,6‐trimethylbenzoate

In the typical reaction of hydroxide ion with a methyl ester, the hydroxide attacks the carbonyl carbon of the ester, resulting ultimately in elimination of methoxide. Given the basic conditions, the ...
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8 votes

Why can you not make a compound with a quaternary alpha carbon using malonic ester?

Double alkylations of the $\ce{CH2}$ centre of malonic esters do work! Have a look at this marvel by R. P. Mariella and R. Raube, published in Org. Synth., 1953, 33, 23 EDIT 1 The use of sodium ...
8 votes
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Does the Dieckmann Reaction proceed via the conjugated enolate of the product?

The first four steps (i.e. the main reaction) are conducted under basic conditions due to the presence of alkoxide. When that reaction is complete, the result is the deprotonated ketoester--the ...
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8 votes
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Are there amide versions of lactides and lactones?

Amide analogue of lactons are lactams, their tautomeric forms are lactims. Citing from the IUPAC Nomenclature of Organic Chemistry (Preferred names 2013): P-66.1.5.1 Lactams and lactims ...
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8 votes

Why do amides require much harsher conditions for hydrolysis than esters?

Dimethyl acetamide (DMA) is less susceptible to hydrolysis than ethyl acetate (EA). This statement is true for aqueous acid or base. The infrared (IR) frequency for the carbonyl group of DMA is 1662 ...
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7 votes
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How does this brominated intermediate lose its methyl group?

A methyl cation definitely won’t leave by itself. However, you can consider bromide ions floating around in solution. These bromide, being nucleophilic can attack the methyl group in an $\mathrm{S_N2}$...
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7 votes
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Routes of formation of esters with highest yield

Option 2 generally gives higher yields. This is because option 1 (Fischer esterification) usually results in an equilibrium mixture which contains significant amounts of products and reactants, ...
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7 votes
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How can rotamers of alpha-keto esters be named to distinguish between different geometries?

The IUPAC recommends s-cis and s-trans for the rotamers of conjugated dienes. The nomenclature derives from having a "cis-like" or "trans-like" geometry about a sigma bond. I feel like something ...
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7 votes
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Formation of Lactone from 5-amino-decanoic acid?

I doubt your book is asking you to convert this molecule into a lactone. This would be very hard to do. It could, however, be easily converted into a lactam. 5 and 6 membered lactams are formed by ...
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7 votes
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Finding the mystery ester strucuture using NMR

Prediction software always has its limitations, and there is always a degree of error in the calculation. For the ChemDraw predictions, you will see that for the 3 aromatic environments, it has done 3 ...
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7 votes
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Which side of the C-O-C bond breaks in esters during hydrolysis in basic medium?

To answer this,Think about how an ester is formed. In the formation of an ester, wherin you react an alcohol with an acid in presence of conc.$\ce{H2SO4}$ $\ce{RCOOH + R'OH -> RCOOR' + H2O}$ Now ...
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7 votes

Sulphuric Acid in Esterification Reaction

The esterification is not the only thing catalysed by sulphuric acid. Basically, it’s catalytic activity is protonation of whatever feels happy enough to be protonated. In your desired esterification ...
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6 votes
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Formation of methyl esters

Both methods are used in practice (and a a lot more exist). Diazomethane is a last resort method when everything else fails. For example you might have a molecule that is acid sensitive or heat ...
  • 1,526
6 votes

What is the difference between the esterification and transesterification?

You are getting too specific as though these are biological processes. They do not have to be... ANY ester made is an esterification reaction. So any ester can be transesterified into a different ...
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6 votes
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Choice of base for malonic ester synthesis

It's unnecessary. In the reaction you are suggesting, the enolate would have to attack the carbonyl double bond from above. The optimum angle of attack is roughly $107^\circ$ but since both the ...
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6 votes

Retrosynthesis of a lactone

The key to this synthesis should be — in my opinion — how to generate the two hydroxy functions with anti stereoselectivity starting from at least one achiral reagent. Most of the time you would ...
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6 votes

What is the name origin of ester?

Just to add another resource besides the excellent find by Nilay, in Organic Chemistry, The Name Game, it mentions ester from German Essigäther (acetic ether) an early name for ethyl acetate The ...
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5 votes

How would I go about making an ethyl ester from vegetable oil?

The biodiesel process should work well, you will need just slightly more aggressive conditions (i.e. slightly more catalyst, slightly higher EtOH excess, and/or slightly longer time) to make ethyl ...
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5 votes

Why can you not make a compound with a quaternary alpha carbon using malonic ester?

Traditional malonic ester synthesis post-processing includes hot acidic hydrolysis, which should lead to substituted malonic acid. However, such acids are prone to decarboxylation, leading to tertiary ...
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