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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 ...
orthocresol's user avatar
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16 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 ...
Nilay Ghosh's user avatar
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11 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 ...
Andrew's user avatar
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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-...
permeakra's user avatar
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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 ...
Mathew Mahindaratne's user avatar
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 ...
iad22agp's user avatar
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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 ...
mykhal's user avatar
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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 ...
user55119's user avatar
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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 ...
long's user avatar
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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 ...
gannex's user avatar
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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 $\mathrm{S_N2}$...
Jan's user avatar
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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 ...
Jan's user avatar
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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 ...
SubZero's user avatar
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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 ...
Jan's user avatar
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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 ...
DrAzulene's user avatar
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Why doesn't self condensation occur in acetoacetic ester synthesis

Self-condensation is typically not an issue with 1,3-dicarbonyl compounds, such as the one in your question. Why? Due to their acidity ($\mathrm{p}K_\mathrm{a}$ around 9 to 11), most 1,3-dicarbonyls ...
Tan Yong Boon's user avatar
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 ...
AChem's user avatar
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6 votes
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Reaction of methyl triphenylbenzoate with concentrated sulphuric acid

The conditions are concentrated sulfuric acid so there is no water present to hydrolyse the ester. If it was dilute sulfuric then you would get the hydrolysis. This reaction proceeds by protonation of ...
Waylander's user avatar
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6 votes
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How to name an ester with an alkene or alkyne as the R group?

According to the current version of Nomenclature of Organic Chemistry – IUPAC Recommendations and Preferred Names 2013 (Blue Book), the names of esters are generally formed by placing the alcoholic ...
Loong's user avatar
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5 votes
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Naming alkyl groups of an ester

You are going about naming them incorrectly, try breaking it into two parts: the conjugate base of a carboxylic acid and an alkyl group. $\hspace{5.9cm}$ Combining the two, we get: $\hspace{6.9cm}$ ...
ringo's user avatar
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Which electronic effects are responsible for the reduction of nucleophilicity of a hydroxy group orthogonal to an ester?

If we focus on the 2-oxo-3s-hydroxy-tetrahydrofuran the electronic effects present are the hyperconjugation and the dipole minimization. "Both effects contribute to the preferred (Z)-conformation of ...
Another.Chemist's user avatar
5 votes
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Is Nitroglycerine a Nitro Compound or an Ester?

The Oxford dictionary is correct. A nitro compound is defined by the $\ce{-NO2}$ functional group, but only if that group is attached to a carbon atom. Once an additional oxygen is added, the ...
Jan's user avatar
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5 votes

Retrosynthesis of a lactone

The first idea that comes to mind is an aldol, as you pointed out too: The only thing left to figure out is what aldol conditions to use to achieve enantioselectivity and the enantioselective ...
logical x 2's user avatar
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Is the reaction between a carboxylic acid and alcohol endothermic?

When in doubt, go find data. Here is a typical such reaction - the esterification of ethanol and acetic acid to make ethyl acetate. $$\ce{CH3CH2OH + CH3CO2H -> CH3CO2CH2CH3 + H2O}$$ The following ...
Ben Norris's user avatar
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5 votes

selective hydrolysis problem

If you use methanol as a solvent and add a suitable base, you should end up with the correct product, since any MeOH attacking the protecting group you want to keep will simply re-form the methyl ...
NotEvans.'s user avatar
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5 votes
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Can citric acid create a polyester?

The esterification of carboxylic acids with tertiary alcohols usually occurs by an SN1 mechanism wherein the oxygen of the alcohol is protonated and a tertiary carbocation is formed. It in turn reacts ...
user55119's user avatar
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5 votes
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Residual catalyst leaching from PETE

Let's ignore the safety aspect here, and focus on the 'if i bathe the jug in water so that all the antimony can leach into the water and wash the jug one more time, can all the antimony be removed ...
long's user avatar
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