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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Why is the reaction rate of tert-butyl chloride solvolysis faster in 80% water/20% acetone, than in 70% water/30% acetone?
The solvent is polar protic, so the mechanism is SN1. However, I don't understand how the composition of water and acetone in the solvent affects the reaction rate.
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Can we always use the planar representation of cycloalkanes instead of their true conformations to study their stereochemistry and chirality?
When I have drawn stereoisomers of substituted cyclohexanes and checked if they are chiral, I typically represent the ring as a planar hexagon and look for symmetry elements. For example, I would use ...
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What happens when iron(III) chloride is dissolved in ethanol?
I dissolved $\pu{25 mmol}$ $\ce{FeCl3*6H2O}$ in $\pu{25 ml}$ ethanol and got a clear ethanol solution of $\ce{FeCl3}$ 4 days ago. And I keep it in a drawer from light these four days.
However, when I ...
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Are the physical and chemical properties of a molecule an average of the properties of its conformers? [closed]
Conformers sometimes differ in chemical reactivity. For example, only certain alkyl bromide conformers have the appropriate geometry to undergo elimination via an E2 mechanism. I imagine that ...
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Is there a formal definition of “identical” molecules?
I was reading about atropisomers and their impacts on drug design, and I started wondering whether we have a formal definition for identical molecules. Atropisomers are not the same molecules because ...
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Detecting epoxy in a polyester powder coat paint
I have 2 steel parts which were both powder coated in a polyester powder coat, however one of them does not perform exactly as I would expect it in my unusual use case which depends on temperature. I ...
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Whats a good solvent to analyze amygdalin in FTIR?
What solvents would be good to analyze amygdalin using FTIR spectroscopy? Will carbon tetrachloride react with the amygdalin if used as a solvent?
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How to obtain reliable ligand binding energy in QM manner?
I wish to compute the binding energy of the ligand to the known cavity of the receptor.
My idea was to:
Perform docking to the recognized binding site using AutoDock Vina
Export bound ligands and ...
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Can a non-rate determining step control what products form in a reaction?
In Organic Chemistry by Clayden, the stereoselectivity and regioselectivity of the E1 mechanism is explained in terms of the differing transition state energies (and therefore rates) of the possible ...
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M- 15 Peak of 1-pentene in EI-MS [closed]
This is the spectrum of 1-pentene.
And my professor says that the peak M-15 (55) came from this process:
But how this is possible, when I tried to prove through mechanism, no one situation match ...
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Racemization at stereogenic centre [closed]
I am getting a bit confused about why the configuration at the optical centre changes from d to l after enolization?
Any stereogenic centre next to a carbonyl group will be destroyed by enolization. ...
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Compare acidic strength of two different hydrogen in a Compound (2-hydroxycyclohex-1-encarboxylicacid)
I want to compare acidic strength between hydrogen-(a) and hydrogen-(b), I am getting answer as (a) but my classmate and my teacher said that (b) will have more acidic strength. I think (a) should ...
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Is there a general single term for benzylic-like positions in non-benzene aromatic rings?
This is a simple vocabulary question. Is there a single chemical term in general use that generalizes the concept of "benzyl" to aromatic but not necessarily benzene rings?
For example, in ...
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Why do the two layers of a phospholipid bilayer stick together?
Every answer I can find about why phospholipids form a bilayer says the same thing: hydrophilic heads associate with water, hydrophobic tails do not, so they arrange themselves with heads facing ...
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Nucleophilicity order among the following?
This question is irritating me up. In the given question, the -ve charge on O atom in (1) and (4) is delocalised, in (4) the charge is more delocalised then in (1) due to more resonating structures. ...
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Why is a ring carbon C-R of a substituted ferrocene more downshifted on 13C-NMR?
Upon assigning $\ce{^{13}C}$-NMR for 1,1'-bis(α-methylmethanol)ferrocene, we discovered the substituted FcC-CH peak (95.14 ppm) was more downshifted than the CH-OH peak (65.59 ppm) as was confirmed by ...
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Is hard tap water useful for "salting out" a liquid organic solute?
We use methylene iodide ("MI", CH2I2) as a heavy liquid for sink-swim mineral separation. We use acetone to wash the MI off of the minerals and glassware after we're done. MI is pretty ...
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in the reaction of aldehydes with NaHSO3 why will sulphur's lone pair act as nucleophile instead of O-
aren't negatively charged species like oxygen anion more nucleophilic than neutral atom like S
why cant O- which is bonded to na act as nucleophile
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Resorcinol turned brown [closed]
I stored resorcinol in a transparent plastic container with an airtight lid. There was some air captured inside the container too. After some days, it turned brown. please tell what happened to it?
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Does each liquid in a binary mixture boil at its boiling point? [closed]
I have been looking for an explanation and can't seem to find one, so I am asking my question on this forum. I appreciate your responses.
Consider a binary mixture of cyclohexane and toluene (50% mol:...
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How do longer chains and more cis-double bonds affect melting point and viscosity of fatty acids?
In fatty acids, longer chains increase the melting point (and viscosity) by increasing London dispersion forces. Inversely, more double bonds decrease the melting point.
What happens when both chain ...
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What is the hybridization of the carbon atom in cyclopropenyl carbocation?
The hybridization of the carbocation in the cyclopropenyl carbocation (which is aromatic) should be sp as it as the + and also is in a ring. But the carbocation has a sp2 hybridization, why?
For ...
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What kind of isomers are ethyl butanoate and propyl propanoate?
Are ethyl butanoate (1) and propyl propanoate (2) metamers or functional group isomers? My book claims they are metamers, but here one group is $\ce{-CO-OR}$ and another is $\ce{-CO-OR'}$ where $\ce{R}...
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Why do chlorophyll need to be dissolved in organic solvents to observe fluorescence?
First, chlorophyll extraction was done with ethanol. I used my phone's flash light to see the fluorescence which was a little pinkish red. Then, I added an ether solvent to the extracted chlorophylls(...
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Threshold of steric hindrance for the axial position in cyclohexanes
My professor mentioned that isopropyl is able to go into the axial position on the chair conformation of a cyclohexane, while tert-butyl cannot. This made me wonder then, at what point is a ...
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What is the code in Harmonized System for NGL, LPG and LNG?
I am trying to research trade statistics related to oil and gas using BACI Database. But I am confused about the product codes I should use.
I read an article explaining the difference between Natural ...
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3-Step Transformation to Humulone
I have some ideas on how this transformation may occur. We're currently studying Ch. 3 (Polar Rxn's under Acidic Conditions) from Grossman's book.
I've found some data online that shows we can perform ...
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Why β-proton of 7-hydroxycoumarin is more deshielded than α-proton?
Umbelliferone (or 7-hydroxycoumarin) has the following signals in the 1H-NMR spectrum:
I don't know if my question makes sense but why the H3 is more shielded than H4 in the α,β-unsaturated lactone? ...
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What is the relationship of the following compounds? [closed]
What is the relationship of these following compounds? My guess is they are constitutional isomers. However, a couple of people said that they are enantiomers of each other. Which one is correct?
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When can lone pairs participate in aromaticity? [closed]
Basically, I'm confused on when lone pairs can participate in aromaticity, by the Huckel definition. Why can lone pairs on a carboanion be aromatic? I thought carboanions are sp3 hybridized, and the ...
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Which one has higher priority in CIP rules -- O or OH?
I know that if the atom is the same, I have to look at the next atom. In the first choice, Oxygen is not connected to any other atom (besides the chiral carbon). It is an anion. Whereas in the second ...
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NaOt-Bu + chloroethane
What is the major product formed by reaction of sodium tert-butoxide and chloroethane?
I thought NaOt-Bu is a bulky base and the major product will be ethene due to E2. But the answer says t-butyl ...
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What determines the higher priority in CIP rules, if both groups have the same atoms?
Which of the following groups has the highest priority in the Cahn-Ingold-Prelog sequence rules?
a) CH2CH3
b) CH=CH2
c) C≡CH
d) C(CH3)3
I narrowed it down to either C or D. The carbon in answer C is ...
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Does norcamphor have enantiomers?
The following two molecular structures have two chiral centers, so in total four chiral centers:
I did the absolute configuration multiple times and I keep getting R,R and S,S, which should be ...
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Can dichloromethane be used as a replacement for chloroform in the MBAS assay?
I'm trying to perform an MBAS assay but my supervisor says we do not have chloroform available. I was wondering if dichloromethane would do the trick in its place i.e. filtering out any anionic ...
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How to add any polymer to azobenzene?
I want to make a polymer by adding two polymeric substituent groups to azobenzene (I would like only N-azobenzene-N where N is a polymer and repeats). I have been reading about how they make the ...
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Major product formed when HBr is added to 1-phenyl but-2-ene
Addition of $\ce{HBr}$ to $\ce{Ph-CH2-CH=CH-CH3}$ possibly yields two products:
$\ce{Ph-CH2-CH2-CHBr-CH3}$ or
$\ce{Ph-CH2-CHBr-CH2-CH3}$
Which one of them should possibly be the major product? ...
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1,1-Diphenylethylene subproduct/impurity
I'm working with 1,1-diphenylethylene and I've observed that, if left at room temperature in the air atmosphere, a white insoluble powder forms. I'm unable so dissolve this powder in every solvent ...
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Does acrylic resin in acetone react with the same acrylic resin in ethyl acetate?
I am not at all familiar with organic chemistry. I am working in museum conservation where an acrylic resin (such as Paraloid B-72) is mixed acetone and sometimes ethyl acetate to produce a resin for ...
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Does the ‘e’ from ‘-yne’ get dropped in compounds of higher functional groups?
What is the way of representing a triple bond in a compound of a higher functional group, like alcohol? Does the ‘e’ from ‘-yne’ get dropped like in the case of the ‘-ene’ suffix?
For example, would ...
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Mechanisms: What is the difference between the top chemical and bottom chemical on an arrow for a mechanism?
I’ve heard the top chemical that is on top of the reaction arrow represents the “first step”, and bottom is “second step” when referring to a mechanism. My question is will the bottom chemical always ...
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API to get GHS info given substance / CAS #
Is there an API that can provide the GHS info for a given substance / CAS #?
If not, which website is the most extensive to get GHS info for a given substance / CAS # in human-readable format?
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Does single swap rule apply to in-the-plane bonds?
When forming enantiomers, does the single swap rule (swapping 2 of the atoms directly bonded to a chiral C will give its enantiomer) apply, even when we're switching bonds that are in the plane?
For ...
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Stereochemistry R,S configuration
I'm trying to find the R/S configuration of this molecule right here:
At first I tried to find the rotation and then reverse it (since H is pointing outwards), I got an S configuration (drawn poorly ...
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How can a molecule with a double bond on one side have a plane of symmetry, and thus, be achiral?
Does norbornene have a plane of symmetry? Is norbornene achiral or chiral?
I think norbornene is chiral since there is a double bond on the only one side. Thus, there is no plane of symmetry. The ...
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Why does 2,3 dichlorobutane have 2, and not 3, stereoisomers
I understand how and that the R,S and R,R stereoisomers are different.
But I don’t see why the R,R and S,S compounds are stereoisomers and not meso compounds with each other.
Online it says that ...
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Is there any book for chemistry which has all the reactions in it ? A book of just reactions [closed]
Is there any book for chemistry which has all the reactions in it ? A book of just reactions. I have gone through way too many but each just explains the types of reaction and to get all the reactions ...
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How does Hammond's Postulate explain the greater selectivity of Bromination over Chlorination?
I know that Hammond's Postulate states that related species are closer in energy are also closer in structure. Thus, bromination's transition state resembles its products, while chlorination's ...
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When it comes to Intermolecular Forces, when the chain length of a molecule increases, is there more or stronger dispersion forces?
I have been told by my highschool teacher that there are more dispersion forces rather than stronger.However, reading up on articles, I have discovered that some explain the increase in boiling point ...
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Contaminants in Ion Exchange Chromatography significance?
I am a high school senior and decided to do a project on the essential amino acid composition of varying vegan protein mixtures. I have run into a problem concerning protein purification. One of the ...
