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.
10,206
questions
1
vote
2
answers
76
views
Mechanism of deprotection of enol thioether
I was reading some enolate chemistry from Carruthers textbook and came across the selective alkylation of unsymmetrical ketones. The reaction involves blocking one alpha-position of the ketone using ...
- 292
-3
votes
3
answers
213
views
When does negative charge represent a pair of electrons?
Probably a stupid question but it has been bugging me for quite some time.
I was reading Clayden (organic chemistry textbook) and in it, the author gives an example of $\ce{OH-}$ and $\ce{BH4-}$ to ...
- 13
0
votes
0
answers
31
views
Solubility of fluoroalkanes [duplicate]
I know haloalkanes generally aren't soluble in water due to their inability to form hydrogen bonds in water, despite being moderately polar. I was wondering why this is the case with fluoroalkanes too ...
0
votes
1
answer
48
views
What is the effect of an electronegative atom being close to (but not directly bonded to) a carbocation?
Does oxygen in 1-methoxy-2-methylpropan-2-ylium affects the tertiary carbocation? Is it destabilized due to its electronegativity?
- 1
1
vote
1
answer
60
views
H-NMR Analysis of C15H24O
I was able to figure out that the structure of this compound was a benzene ring with 2 equivalent trimethyl groups to give the 18H singlet. Another non-equivalent methyl group to give the 3H singlet. ...
- 11
0
votes
1
answer
45
views
Does -OTMS group transfer to a different carbon easily?
In this organic transformation question, (https://imgur.com/a/nr0LHUm) I understand that the intermediate below gets formed, but why does it lead to the final product?
- 55
0
votes
0
answers
58
views
Distillation of free fatty acid from soya acid oil
I have soya acid oil with FFA percentage of about 40. After degumming and glycerolysis I am able to bring down the FFA percentage to 5. It does go down to about 2 percentage but it takes an enormous ...
- 1
1
vote
0
answers
51
views
Improving the solubility of p-dibromobenzene in a reaction with water as solvent
I am trying to react p-dibromobenzene with Fenton's reagent (in an attempt to see if I can add alcohol groups to the ring and observe if there is any specificity in its addition), in this case using %...
- 31
1
vote
1
answer
48
views
Adding colours to polymers
It is said that some polymers can be dyed, but I am not sure about the mechanism behind.
Let me take an example. In anodization, aluminium oxide can be coloured since there are tiny pores for the ink ...
0
votes
0
answers
186
views
Why does ethanol decrease viscosity of a high pH carbomer solution more compared to water
Carbomer 407 is made up of acrylic acid that undergoes polymerisation to form a long linear structure. At higher pH, the carboxylic acid functional groups will dissociate to form carboxylate ions. ...
- 1
-4
votes
1
answer
66
views
Does ammonia gas neutralise Hcl salt of amines in dry non polar medium [closed]
I am trying to basify/neutralise the $\ce{HCl}$ salt of amine and other organic compounds by bubbling dry(or semi dry) ammonia gas through a column of the salt suspended in a non polar solvent like ...
- 11
2
votes
1
answer
146
views
Explain the mechanism of the following reaction, which involves a 1,2-alkyl migration with double inversion of configuration
I came across the following reaction, whose mechanism is said to involve a 1,2-alkyl migration with a double inversion in configuration. The reagents used were nitrous acid (generated in situ) ...
- 292
3
votes
1
answer
372
views
Is size or electronegativity more important in acidity?
For the molecule below, is the hydrogen with the oxygen more acidic or is it the one with sulfur?
Since both parts have the same number of resonance structures, I'm guessing it just boils down to ...
- 323
1
vote
1
answer
116
views
Why does Williamson's Ether Synthesis ONLY follow Sn2 Mechanism
I am a high school student learning chemistry and my knowledge of organic chemistry is very limited, so pardon me if I am asking a nonsensical question.
While practicing organic, I came across the ...
1
vote
1
answer
113
views
What shifts protons on a benzene ring to lower ppm?
Why do these protons appear at 6.9 and 6.93 ppm, at lower ppm value? I assumed it was due to the anisotropic effect, specifically I thought the circulating (pi) electrons induced a magnetic field ...
- 13
2
votes
0
answers
40
views
Question on Lithiation Site in Directed Metalation
I have seen this from the Baran group meeting material
Here, why does lithiation not happen at C2 position? Why does tBuLi specifically litigate the C4 position only?
- 55
0
votes
1
answer
33
views
What resin is appropriate for construction of a gasoline/ethanol fuel tank
I am building a epoxy resin/glass reinforced plastic (epoxy/GRP) gasoline tank. The expected service life is 30 years.
I've read that epoxy is relatively resistant to gasoline (some better than others)...
- 109
0
votes
0
answers
42
views
Why is the 'cis-1,3-dimethylcyclobutane' conformation of both methyl groups at the bottom more unstable than both at the top?
I'm having trouble understanding why both methyl groups on top of the ring is a more stable conformation than both at the bottom of the ring.
I found a reasoning that says the steric strain between ...
- 81
2
votes
1
answer
66
views
How to make a benzyl position more electrophilic?
I have to write a synthesis (just below) of a molecule and propose reactants and conditions :
But I have a problem with the 2nd step. Where I need to do the ether.
Apparently it's very difficult to ...
- 71
0
votes
0
answers
30
views
How does a transition metal(eg Zn,Pd,Pt etc) break the hydrogen bond in catalytic reduction
I want to know what exactly happens with the hydrogen molecules and transition metals in catalytic reduction leading to breaking of hydrogen bonds and forming two hydrogen atoms
1
vote
0
answers
51
views
TMSiBr and Oxalylchloride for ester cleavage
I am wondering what is the advantage of using TMSiBr do perform an ester cleavage in comparison to perform chlorination first for example with oxalylchloride or thionylchloride and than add water?
- 171
1
vote
0
answers
41
views
Esterification of phosphonic acid chloride is working with isoprenol but not with prenol
I am performing an esterfication reaction between an activated phosphonic acid (chloride) and a series of alcohols. Until now, I was not able to make the reaction work with prenol, while isoprenol is ...
- 171
5
votes
2
answers
1k
views
Why are "vinylic" and "allylic" carbons named so?
I find it hard to remember which is "vinylic" and "allylic" carbon, so I feel it would be easier to remember if I know the reason why they are named so, like their word root ...
-4
votes
1
answer
111
views
Can 'Beta-hexachlorocyclohexane' (C6H6Cl6) be Optically named?
I have not found RS configuration in Beta-hexachlorocyclohexane(C6H6Cl6) anywhere but tried to give it, although some books say that it can not be named in this configuration. So, is it named ...
1
vote
1
answer
81
views
What is the rate of hydration in the following compounds
I came across a question :
What is the order of rate of hydration in the following compounds:
My attempt to this question was checking the stability of carbocation. As III has a possibility of 3* ...
- 23
1
vote
1
answer
123
views
Substitution or elimination when a chloroalkene reacts with NaOH in ethanol?
NaOH + EtOH will eliminate the Cl atom forming a double bond. At least, that's what I think. 3 could also be a viable answer since the OH can also attack the said double bond (this is probably not ...
- 13
2
votes
2
answers
108
views
Cyclopentadiene planar
Cyclopentadiene has a sp3 carbon yet it is said to be planar. I am not able to understand and haven't been able to find a credible source. Some sources say it to be non-planar
- 29
0
votes
1
answer
71
views
Why does a hydroxyl group decrease the acidity of an Aromatic ring?
We are currently learning about resonance and induction, but I am confused why the addition of the hydroxyl group increases the pKa. As oxygen is more electronegative, should it not increase the ...
0
votes
1
answer
71
views
Why does alpha-carbon substituents increase the rate of E2 reactions?
The reason for more reactivity of more substituted alkyl halides for E2 Reaction is said to be due to the more stability of its more substituted alkene character having transition state but here (...
- 89
0
votes
0
answers
54
views
How does a pyrrole react with its C2?
First of all, thank you for reading my question. There is a mechanism I read where the pyrrole reacts with its C2 but I can't draw the arrows so I don't know if I am correct to think that :
the ester:...
- 71
3
votes
1
answer
1k
views
Does a slippery liquid leak through pipe fittings?
We use a 6% potassium hydroxide (KOH) solution for electrolysis. This solution is known to be "slippery". Does this mean that it will leak/seep through NPT pipe threads more than plain ...
- 187
3
votes
1
answer
212
views
Lithium aluminium hydride
Lithium aluminium hydride is an important reducing agent in organic chemistry.
Since I cannot find the half-equations telling how this reducing agent performs its action, I am wondering, is lithium a ...
1
vote
1
answer
90
views
Standard electrode potentials
I know that many substances have their own standard electrode potential and they can be arranged in he electrochemical series. For example, the standard electrode potential of iron is -0.440V.
Since ...
-4
votes
1
answer
66
views
Alcohols and bromine [closed]
As far as I know, bromine can act as an oxidising agent. But when propan-1-ol is mixed with bromine water, there is no reaction.
Why bromine cannot oxidise alcohols? Is the reaction available if a ...
- 325
-2
votes
1
answer
42
views
Clear polystyrene bottle holder repaired with butyl acetate glue. Is it safe to use in the fridge?
I've successfully repaired my fridge's bottle holder, which is made of clear polystyrene, using butyl acetate glue.
While the glue smelled at the time I was gluing, the repaired bottle holder no ...
- 107
2
votes
1
answer
164
views
Can Acyl halides react with PCl5, if not, why?
I was searching for reaction of $\ce{PCl5}$ with carboxylic acids and found this mechanism:
Here a corresponding acyl chloride is formed from a carboxylic acid.
Now I doubt if this is the final ...
- 89
-2
votes
1
answer
81
views
Does lime juice "alkanize" in the body? [duplicate]
My brothers and I have a dispute. They claim lime juice alkanizes in the body. I contest as an acid it remains acidic in the body. My guess is they are confusing "lime water" with "...
- 7
-4
votes
1
answer
67
views
Reaction of eugenol with concentrated hydrobromic acid in the presence of gaseous hydrogen bromide [closed]
DISCLAIMER: I am not using any of this information to commit a crime, my university has a license from the relevant authorities to investigate clandestine chemical procedures.
We are investigating an ...
-2
votes
1
answer
64
views
Why having a carbonyl group is not contributing to binding energy
I am carrying out a virtual screening project for a protein receptor to identify possible ligands (small molecules). After the virtual screening, molecular dynamics, and MMGBSA calculation, I ...
0
votes
0
answers
201
views
What mechanism do reaction of PCl5 follows, SNi or SN2?
I was taught that $\ce{PCl5}$ reacts with alcohols by $S_Ni$ mechanism as shown below:
Here it can be seen that $\ce{PCl5}$ exists as $\ce{[PCl4]+[PCl6]-}$ and so lone pair of the alcohol is donated ...
- 89
1
vote
0
answers
31
views
Avoid triethylphosphate as a side product during P-C-P coupling reaction with diethylchlorophosphate with LDA
I have a reaction in which I perform a deprotonation of an acidic proton at a phosphate and later do a P-C-P coupling. The coupling partner is diethylchlorophosphate. Deprotonation is performed with ...
- 171
4
votes
0
answers
33
views
Stereoselectivity in catalytic hydrogenation
Why is cis stereo selectivity is observed in this case? See image below.
I can't think of any reason why cis addition is major.
In my opinion, the ratios should be opposite because of easier ...
- 71
0
votes
0
answers
56
views
how can a chemist detect the element boron in a sample of ordinary dust?
After the world trade center attack 22 years ago, the USGS sampled dust from the world trade center site and from lower Manhattan. They tested for every solid element except boron. I'm curious about ...
- 29
4
votes
1
answer
60
views
Would having a greater H-bond donor count make a substance more readily enter a twig?
Yes, weird plant scientist asking weird plant questions...
Background:
I am looking at how the twigs of trees absorb water, a poorly understood means by which trees alleviate water stress. Of 4 ...
- 41
0
votes
0
answers
127
views
Why is m-fluorophenol less acidic than m-chlorophenol?
Why is m-Fluorophenol less acidic than all the other m-Halophenols, even though it has the most inductive effect
The data is from :
A guidebook to Mechanism in organic chemistry for the JEE, 6th ...
0
votes
0
answers
60
views
How does tBu2Si(OTf)2 react in uridine in DMF at 0°C
I have to write the mechanism of a four steps reaction that aims to transform uridine into a deoxythymidine by following these steps :
(tBu)2Si(OTf)2, DMF, 0°C
ClCSOPh, DMAP, 20°C
AIBN, Bu3SnH, 80°C, ...
- 71
-2
votes
1
answer
61
views
How does polarity increase when electron density in oxygen decreases when comparing acidity
My book says the following statement:
Due to the higher electronegativity of $sp^{2}$ hybridized carbon of phenol , the electron density in oxygen decreases. This increases polarity of O-H bond and ...
- 137
-2
votes
1
answer
78
views
Why is it okay for the central carbon to lose a bond when forming a resonance structure for acetone?
As the title reads, I'm confused as to why it's okay for the central carbon in acetone to have a +1 formal charge when we push the electrons from one of the bonds with oxygen to form a lone pair and ...
-4
votes
1
answer
91
views
What will be the product if ethane reacts with SO2?
At first I thought it was Reed's reaction but then I looked up the reaction and the reactant was actually $\ce{SO2Cl2}$ (sulfuryl chloride).
I couldn't find the product which would be produced when ...
- 3
-2
votes
1
answer
25
views
Formation of cocrystals troubleshootin
In cocrystal formation what would the possible reason be for the precipitation of an amorphus oily precipitate not suitable for PXRD? Solvent was DMF and the reagent were L-thyroxine and ...
