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Questions tagged [organic-chemistry]

Use this tag for questions relating to organic molecules and their properties (structure of organic molecules, spectroscopic properties, reaction mechanisms, stereochemistry etc). DO NOT use this tag as the only tag in your question, as this tag by itself cannot appropriately classify your question. Always use this tag in addition to other more specific tags.

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What is the pKa of choline chloride?

I am looking for the pKa of choline chloride, which should be higher than 7 (around 10?), but I cannot find any reference value.
David Moldes's user avatar
1 vote
0 answers
59 views

Why this problem happens on LC-MS chromatogram?

I used to analyse my compounds on LC-MSdevice with 95% water/5% acn +0,1 formic acid. My column is hypersilgold (C18). When I did my acquisition, I obtain this chromatogram sometimes, and it doesn't ...
ChemistryTryHarder's user avatar
2 votes
0 answers
52 views

Why do stable carbocations form majority of the products?

In my A-level chemistry course, one of the topics is on alkenes in which we have to learn that the major product of $\ce{H-\color{green}{X}}$ reactions with unsymmetrical alkenes is the one formed via ...
John's user avatar
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0 votes
1 answer
74 views

1,4 (conjugate) addition in unsaturated aldehydes and ketones

When carbonyl compounds react with grignards, they usually give a 1,2 addition (direct addition) product. However, under certain conditions, they give conjugate addition (1,4 addition) product as the ...
Ayanokouji Kiyotaka's user avatar
-2 votes
1 answer
37 views

Synthesis Sec - Butyl Bromide from alcohol

The question is to make Sec-butyl Bromide from alcohol. From what i have read, 2° and 3° alkyl bromide and alkyl iodide cannot be formed with Conc H2SO4 as it will make it into alkene. I have tried P4 ...
Aum Pandya's user avatar
-1 votes
2 answers
456 views

What are the resonating structures of toluene?

I initially made the resonating structures by first converting toluene into a toluene carbocation. But the resonating structures of a neutral molecule should be neutral. So what are the correct ...
matgsh's user avatar
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3 votes
2 answers
496 views

Reaction of cyclohexene with HCO3H

Reaction of cyclohexene with a peroxy acid like mCPBA gives an epoxy acid according to Prilezhaev Reaction. I think it should work with any per acid according to the Mechanism here. But HCO3H gives ...
Joy8144's user avatar
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0 votes
1 answer
133 views

Aromaticity of a fused ring compound

On a test, I marked this as aromatic, but the answer key says it's wrong. My thought process: It has 10pi electrons, so it follows Huckel's rule All carbons are sp2 hybridized It is cyclic Every atom ...
nidhishtyagi's user avatar
1 vote
0 answers
27 views

Confusion in Free Radical Reactions with alkenes

I was reading the free radical reactions, therein I saw two almost same(atleast that's what i think) but forming different products. First, we have cyclohexene reacting with Br2 in presence of ...
PinkAura's user avatar
  • 107
1 vote
0 answers
26 views

Comparing Acidic and Basic Strength of organic compounds

If I find out the order of acidic strength of some organic compounds and simply flip them to get the order of basic strength, will it be correct? Is there any case where this logic should be incorrect?...
Tanamay Rathod's user avatar
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0 answers
18 views

How can you find the Absorption of a specific compound in a solution with 2 other compounds using Uv spectrophotometer

I was wondering if there was a way to get the absorption of ascorbic acid in a solution with citric acid and disodium hydrogen phosphate? I’m thinking of measuring the absorption of disodium hydrogen ...
Benjamin's user avatar
1 vote
1 answer
272 views

Can a carbocation ever be more stable than a neutral molecule?

The question is about finding the most stable molecule or species. Now my thought process was that cyclopropenylidene(1) was a carbene so would be unstable even though it is aromatic. Cyclopenta-1,3-...
mechanist's user avatar
-3 votes
1 answer
74 views

What factors do heat of combustion of a organic compound depend on? [closed]

Let's say there are 3 organic compounds A, B, C and you know their structures. How exactly could you go about deducing the order of their heat of combustions? For an example,
Dev Not Taken's user avatar
-4 votes
1 answer
58 views

What shold be the answer to the given reaction? [closed]

Q.75 The final product A, formed in the following reaction sequence is: $$\ce{ Ph-CH=CH2 ->[(i) BH3 (ii) H2O2,OH- (iii) HBr][(iv) Mg, ether, then HCHO/H3O+] A }$$ Options $\ce{Ph-CH2-CH2-CH2-OH}$ $...
Rock's user avatar
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7 votes
2 answers
625 views

Question about the differences of white and grey NaH properties

We are having some problems with the next reaction in our lab. As you can see, is the sulfonylation of an indole in which we use NaH (60% dispersion in mineral oil) as a base. This reaction goes with ...
Alicia's user avatar
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3 votes
1 answer
139 views

Electrolysis of benzyl alcohol in methanol

I am conducting following electrochemical experiment on Au wires in organic medium: I suppose the anodic reaction goes through a benzaldehyde intermediate: The cathodic reaction is hydrogen ...
Mäßige's user avatar
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1 vote
0 answers
24 views

Does nitroprusside test only work for ketones and not aldehydes?

Since the Brady test will be positive for both aldehydes and ketones, we need a way to distinguish between the two. The Tollen's test is only positive for aldehydes (and $\alpha$-hydroxyketones). I ...
AVS's user avatar
  • 491
1 vote
0 answers
29 views

What is the size parameter of the direct red 80 molecule?

Basic information: CAS number: 2610-10-08 Molecular formula: C45H26N10Na6O21S6 Molecular weight: 1373.07 Structural formula: For example: For congo red whose structural formula is demonstrated below, ...
陈永曜's user avatar
2 votes
1 answer
102 views

Is pentalene stable at room temperature?

Pentalene is planar, conjugated and has 8 π-electrons on its periphery, so it can be anti-aromatic. But if we polarize either of the π-bonds adjacent to the central C−C bond, the other ring will ...
shur's user avatar
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4 votes
0 answers
83 views

Does the E1cb elimination mechanism have a first-order or a pseudo-first order rate law?

Elimination reactions turning a single C-C bond into a double bond are classified as E1, E2, or E1cb, depending on the mechanism (concerted or with intermediate), the stereochemical outcome and their ...
Karsten's user avatar
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0 votes
0 answers
20 views

Bonding and antibinding orbital energy difference

Reading Claydens organic chemistry, in chapter 5 it states that Br-Br makes a good electrophile while the C-C in ethane doesnt because the energy difference between bromines bonding and anti bonding ...
Snfkn91's user avatar
4 votes
0 answers
113 views

Hydrolyse a fluorophosphonic compound / Which protective group strategy can I use for phosphonate esters to access the free acid after a reaction?

I have a synthetic problem in my PhD thesis, in which I synthesize a phosphonate ester. To be more precise, it is a phosphonofluoridic compound. In my specific case, the fluorine attached to the ...
raptorlane's user avatar
6 votes
1 answer
294 views

What is the number of different compounds formed from the monochlorination of cis-1,2-dimethyl cyclopentane?

I encountered this question in the Black Book of Organic Chemistry by Ashish Mishra while preparing for a college entrance exam. According to the answer key the answer is 12. I have only managed to ...
Grimm's user avatar
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0 votes
0 answers
31 views

Why does polar solvents favor Ketonization and non-polar solvents favor Enolization? [duplicate]

I was just studying isomerism, when I came across this statement for keto-enol tautomerism: A polar solvent favors ketonization, while a non-polar solvent favors enolization. And I just can't get my ...
Nishant's user avatar
  • 11
-2 votes
2 answers
154 views

Why O-H bond and not C-O bond breaks in Acid Catalyzed Hydration of Alkene?

Recently, while studying Hydrocarbons I came across this reaction (Acid catalyzed hydration of an alkene) What I don't get here is that the breaking of O-H bond (in Step 3) and not the C-O bond, even ...
PinkAura's user avatar
  • 107
0 votes
1 answer
176 views

solubility of glutamic acid in water

As we have learned in school, generally speaking polar molecules can dissolve in solutions with other polar molecules. However in the case of glutamic acid, it appears that it is unable to dissolve in ...
Chem's user avatar
  • 19
0 votes
0 answers
33 views

Stereoselectivity of the homogeneous catalytic hydrogenation of 2-Methylenebicyclo[2.2.1]heptane using wilkinson's catalyst

For the following reaction, 2 products are available: in one, the methyl group is axial, and in the other, it is equatorial. The addition of hydrogen to the double bond is a syn addition to the less ...
CC.chem's user avatar
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0 votes
1 answer
81 views

Isoelectric Point

How do we derive the formula of isoelectric point? pI=(pKa1 + pKa2)/2 I read that isoelectric point is defined as the pH at which degree of protonation in amino group is same as degree of ...
Priyanshu Kumar's user avatar
5 votes
1 answer
190 views

How is nitrogen the most powerful electron donor in aromatic rings?

In Clayden, page 735, Aromatic Heterocycles 1:Reactions: The other simple five-membered heterocycles are furan, with an oxygen atom instead of nitrogen, and thiophene, with a sulfur atom. They also ...
zxayn's user avatar
  • 105
0 votes
0 answers
52 views

Why would 1-ethenyl-2,6-dimethylbicyclo[2.2.0]hexane give off 8 H1 signals?

I am trying to figure out this problem, and can only find seven signals, two from the double bond, one from the single bond attached to the double, there is symmetry, so one signal on the methyl, one ...
Benjamin's user avatar
0 votes
0 answers
44 views

Why isn't the dielectric constant for molecules like methanol higher than water using inductive effect?

The dielectric constant of a more polar molecule should be higher than a molecule which is less polar(polarity can be measured by dipole moment), so methanol should have higher dipole moment than ...
Saif's user avatar
  • 35
0 votes
0 answers
59 views

How to remove hexane from nBuLi

As described in a paper, the authors removed the hexane from the nBuLi solution "under reduced pressure". I was wondering if anyone had any experience on how to proceed safely with this ...
The Red Man Jolan Bonelli's user avatar
-1 votes
1 answer
58 views

Mesomeric form and organic reaction [closed]

I'm looking to find all the mesomeric form of the compound A. I don't know how to take it because there is triple bond. I think one bond of the double bond of ceton can go on the oxygen, but after ...
ChemistryTryHarder's user avatar
-1 votes
1 answer
40 views

Ratio of amounts of different mono substituted alkanes (by halogenation)

My problem here is the I'm unable to use the information for reactivity of C-H bonds to calculate the amount of mono chlorides. If anyone can help me in the process, that would be great.
Heisenberg 's user avatar
4 votes
1 answer
463 views

Why is the ketone not attacked by the Grignard reagent/cuprate in this case but a double bond is?

According to the book the answer is (a) Here I assume transmetallation occurs and then the nucleophilic carbon of methyl attacks the ring but what I don’t understand is why the ketone remains ...
Venven's user avatar
  • 51
4 votes
1 answer
130 views

Major product in chloro-sulfonation of toluene

According to Clayden's Organic Chemistry (2e) (p.485) ... and the acid chloride (tosyl chloride, $\ce{TsCl}$) needed to make tosylates can be made from the acid in the usual way (p. 215) with $\ce{...
zxayn's user avatar
  • 105
1 vote
0 answers
120 views

Cation/Anion UV-Vis absorption

I want to understand how the ground state absorption of a molecule shifts if an electron is added or removed. I found these two publications 1 and 2 that observe shifts, but both times a redshift, be ...
Martin 's user avatar
  • 141
4 votes
1 answer
247 views

Why is cyclooctene the smallest cycloalkene to have cis-trans isomerism?

What prevents cis and trans isomers from existing in smaller cycloalkenes, for example, cyclohexenes for more than a short period of time?
Joe Dahl's user avatar
  • 109
0 votes
0 answers
72 views

What is the enthalpy change for elimination reactions of alkyl halide - exothermic or endothermic?

There are a few questions in thermodynamics (with unverified data) that the addition reaction of ethene to give ethyl chloride has a +ve enthalpy change, thereby elimination to give alkene must be ...
Che Mistry's user avatar
2 votes
1 answer
328 views

How to name an ester with an alkene or alkyne as the R group? [closed]

More specifically, see the image down below: Would it be pentan-2-ene-3-yl propanoate? Do you just add the 2-ene to specify the position of the double bond?
Joe Dahl's user avatar
  • 109
1 vote
0 answers
50 views

History of Azeotrope (azeotropic mixtures)

I'm currently researching the history of azeotropic mixtures for an essay, and I've come across some interesting information. The term "azeotrope" was coined in 1911 by English chemists John ...
Max89's user avatar
  • 19
-4 votes
2 answers
134 views

The Role of Acidified Potassium Manganate(VII) in Oxidation of Alcohols [closed]

The chemical equation for the oxidation of ethanol is given as: $$\ce{C2H5OH + 2[O] -> CH3COOH + H2O}.$$ Acidified potassium manganate (VII) solution $\ce{KMnO4}$ is added as the oxidising agent. ...
ZhangJin's user avatar
0 votes
0 answers
53 views

Extended resonance and colour [duplicate]

I was pretty sure that this would've been asked before but I couldn't find anything here. I've noticed that system with multiple benzene rings and pi donating/accepting groups tend to be quite ...
Gaurav Sai Maddipati's user avatar
-4 votes
1 answer
70 views

Definition of alpha-carbon [duplicate]

What is an $\alpha$-carbon, and how can I identify one? The other questions because of which my questions has been termed as duplicated is asking about alpha carbons in alkyl halide , while my ...
Intensed's user avatar
0 votes
0 answers
38 views

Acidic strength of 4-(tribromomethyl) benzoic acid vs 4-(trichloromethyl) benzoic acid

From what I leart from my teacher is that 4-(tribromomethyl) benzoic acid is more acidic than 4-(trichloromethyl) benzoic acid. But I'm not sure what the reason is.According to me 4-(trichloromethyl) ...
Minduelle's user avatar
0 votes
2 answers
141 views

Storing 'Tollens Reagent'?

I have read that tollens reagent is unstable and hence must be freshly prepared before testing. However my school has a bottle of 'tollens reagent' on the shelf for use in organic qualitative analysis ...
Gaurav Sai Maddipati's user avatar
-2 votes
2 answers
104 views

What is the correct reaction mechanism for the following :

The question is : Now, this is what I have done : So I dont know how to proceed to the final product. In some book they tell we need to break the cyclopropane to get the desirable answer but how ? ...
SavageTomato's user avatar
-1 votes
1 answer
97 views

Inductive Effect (R-NH3+ and R-NH2)

Textbooks I've read state that R-NH3+ has exhibits a greater -I inductive effect than R-NH2 does. However, I've also read in places that the + charge in R-NH3+ only represents a formal charge and has ...
Aarchaeus's user avatar
1 vote
0 answers
32 views

Can I Detect Hydroxyl Radicals Using Methylene Blue Spectrophotometry?

I am going to be pulsing radiation into a chamber containing a solution of water and both ferric and ferrous iron. The irradiation event should cause a Fenton reaction to ensue and I'd like to trap ...
Bon's user avatar
  • 51
0 votes
0 answers
33 views

Why hyperconjugation is called as σ to π* donation for alkenes and alkynes?

Why hyperconjugation is called as σ to π* donation for alkenes and alkynes if for C2 lowest unoccupied molecular orbital is σ2p not π*2p?
S K's user avatar
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