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.

Filter by
Sorted by
Tagged with
1
vote
0answers
19 views

Cleavage of 2-Methyltetrahydropyran with HBr

After this cyclic ether is activated with H+, will the bromide attack the more substituted site on the left or the less substituted side on the right? I think it will attack the right because SN2 ...
0
votes
0answers
29 views

Which compound releases more energy upon combustion?

I know that the last two on the right are stable so they are not the answer, but can someone give me a hint on how to decide between the two on the left? what is the way of solving such question, I ...
1
vote
0answers
39 views

What would be the product of this reaction?

A 3 membered carbon ring with a double bond to oxygen from one carbon and a double bond between the remaining carbon with a methyl group attached to one of the carbon is made to undergo acid catalyzed ...
-1
votes
2answers
32 views

What does per-O-acetylated glucopyranoside mean? [closed]

What does per-O-acetylated glucopyranoside mean? Can you please break down the roots?
1
vote
0answers
31 views

Why does acid hydrolysis of glucose-1,6-bisphosphate produce glucose-6-phosphate and not glucose-1-phosphate?

A paper I found details treating glucose-1,6-bisphosphate with 6M HCl to produce glucose-6-phosphate. I'm curious why glucose-1-phosphate (and then even plain glucose) isn't formed instead?
0
votes
0answers
25 views

Best way to handle phosphorus tribromide

I need to do an alcohol bromination using PBr3 and I've never done this reaction before. Reading about PBr3 I found it is water/air-sensitive and the bottle I bought doesn't have a seal. So how am I ...
0
votes
0answers
24 views

How to efficiently weight DCC (N,N'-Dicyclohexylcarbodiimide)?

I have to run a reaction using N,N'-Dicyclohexylcarbodiimide and at room temperature, it is solid, but it's very hard to weigh. I know its melting point is around 40 degrees. Is it better to melt it ...
-2
votes
1answer
89 views

Any examples of reactions where simpler molecules are combined into more complex ones and are endothermic at the same time? [closed]

Can you name examples of reactions that are endothermic and simple molecules are combined into more complex ones at the same time? Like what plants do they take heat and sunlight and they synthetize ...
-1
votes
1answer
32 views

Chromatography- why tM is separated from other peaks? [closed]

tM in Chromatography is the time of exist mobile phase. But, the mobile phase exist together with all the compunds that tasted in the process. So, why in the graph of signal to time we can see a peak ...
-1
votes
1answer
49 views

How to prepare a 10% alcoholic KOH solution? [closed]

I am confused actually. A 10% alcoholic KOH solution means that there is 10g of KOH in 100 ml of ethanol, or 10g KOH in 100 g of ethanol or something entirely different? Also, I understand that the ...
-1
votes
1answer
31 views

Do side chain carboxylic acids need to be protected in peptide synthesis?

Consider the synthesis of the dipeptide Glu–Ala (image). The amino acid Glu (glutamic acid) has two carboxyl groups, where one of them should reacts with the amine group from the other amino acid. ...
1
vote
1answer
65 views

What is “silanol activity”?

In a previous post about how pyridine failed to move much from the baseline of a TLC, I was told to look into "silanol activity". However, I was unable to find a textbook-style description. ...
3
votes
0answers
49 views

Why do nitrogen-containing organic compounds give N2 as the combustion product?

My teacher gave the explanation stating that consider that first the nitrogen in lower state is oxidised to $\ce{N2}$ and then the further oxidation would stop as the $\ce{N-N}$ bond energy of $\ce{N2}...
-5
votes
1answer
32 views

Why polysaccharides are not considered as lipids? [closed]

It is mentioned in my textbook that all lipids have one common trait which defines them :they are insoluble in water;they are hydropohic. I want to ask ,since polysaccharides are also insoluble in ...
1
vote
0answers
30 views

How stable are surfaces functionalized with APTES?

I'm wondering specifically about magnetite micro particles functionalized/silanated with (3-aminopropyl)triethoxysaline (APTES), though I assume the stability would be the same for most surfaces. By ...
0
votes
0answers
18 views

Purpose of water bath- rate of formation of precipitate in haloalkane hydrolysis

In a high school experiment for observing the rate of formation of precipitate with Silver Nitrate in the hydrolysis reaction of different haloalkanes (Chloroalkane, Bromoalkane, Iodoalkane), a water ...
4
votes
1answer
118 views

What is the correct numbering & order for this molecule?

I'm having a hard time understanding why the numbering for this molecule is: 4-bromo-1-tert-butyl-2-methylcycloheptane, instead of: 1-bromo-4-tert-butyl-3methylcycloheptane. Is it just because the ...
0
votes
0answers
119 views

Is nitrobenzene a polar molecule?

So I'm trying to figure out if nitrobenzene is an overall polar or non-polar molecule. I calculated the electronegativity difference of each bond, and according to the ranges I learned in class all of ...
0
votes
0answers
48 views

Which enol form is more stable?

I came across an example today while I was studying tautomerism. It is an example of tautomerism exhibited by acetylactone/1,3-diketone; given under the keto-enol systems under 1-3 migration/triad ...
5
votes
1answer
74 views

Reaction of SeCl4 with alkene and possible consecutive reaction?

There is a reaction that confused me a bit: According to my research on SeCl$_4$, it can be used as a dichlorinating agent for alkenes. However, I am totally confused about the mechanism. I've read ...
0
votes
0answers
22 views

Steady state approximation rate equation for an E1cB reaction

Is anyone able to explain why species 'D' is not included in the steady state approximation derivation for this E1cB reaction? The correct rate equation in the image has been derived first and then I ...
1
vote
0answers
24 views

How exactly do Copper salts help in Sandmeyer Reaction (Halogenation)?

I have searched a quite few sources on mechanism for Sandmeyer's reaction, but couldn't find (and understand) how CuCl for example helps in replacement of N2 from Benzene diazonium chloride and gives ...
0
votes
0answers
20 views

Confusion on the Finkelstein reaction(AKA halogen exhange reaction)

So in the Finkelstein reaction, the iodide ion is supposed to replace another halogen(say chlorine) through SN2 mechanism. But here, Acetone is used, which is a polar aprotic solvent. And in acetone, ...
1
vote
0answers
58 views

Decarboxylation of 2‐cyano‐2‐cyclohexylideneacetic acid [closed]

2‐Cyano‐2‐cyclohexylideneacetic acid (1) is heated and $\ce{CO2}$ is lost: [ Why is this not formed? In other words, why do π-electrons move into the ring?
5
votes
1answer
153 views

Aromatic Character in Percentage?

I was just searching whether Uracil is aromatic or not and in this link$^1$ it is said that (from the abstract): High-level computational methods were tested for the enthalpy of hydrogenation of ...
0
votes
1answer
46 views

Why is boiling point of Ammonia greater than Arsine?

I have previously read that the boiling point of Stibane(SbH3) is greater than Ammonia(NH3) as ammonia is gas at room temperature and no hydrogen bonding exists in the gaseous form of NH3. Hence, as ...
3
votes
1answer
313 views

How is the central carbon in 3‐bromopentane‐2,4‐diol chiral?

My teacher told us the middle carbon in 3‐bromopentane‐2,4‐diol is chiral: $$\ce{CH3-CH(OH)-\overset{\star}{C}H(Br)-CH(OH)-CH3}$$ Since there are two identical groups around it, I would guess it ...
-1
votes
1answer
47 views

Why does Delta H change when the coefficients change in a reaction?

So I understand that if twice as much of the reactants are present, then twice as much energy is released. But isn’t the energy released per mole of reactant still the same? You are just scaling up ...
4
votes
0answers
24 views

Does the mechanism of AChE inhibition by Isoparathion depend on chirality?

It is known that the inhibition of acetylcholinesterase by isomalathion can proceed either with diethyl succinate as the leaving group or thiomethyl, depending on the specific stereoisomer of ...
0
votes
2answers
71 views

Why is H2O a weaker acid than acetylacetone? Shouldn't a hydrogen connected to an oxygen be more acidic than a hydrogen connected to a carbon atom? [closed]

I recently started studying chemistry after a long pause in my education so pardon me if it is a simple question. In the organic chemistry course I am taking, the professor told us that the first ...
10
votes
1answer
461 views

Photochemical reduction of benzophenone: why inverted flask?

I've come across an interesting protocol for photochemical reduction of benzophenone to benzhydrol (diphenyl methanol) with sodium alcoholate in alcohol, the 2nd protocol in https://prepchem.com/...
1
vote
0answers
25 views

Iodometric titration

When you carry out iodometric titration for determining the Peroxide value of a phospholipid mixture, the end point is the solution turning colourless. But, after some time the colour reappears. Do ...
3
votes
1answer
47 views

Deciding which group twists out of the plane when ortho effect takes place

I'm going to take a few stills from 3D conformers of the following compounds available on PubChem in which ortho effect is applicable to show what I'm referring to. 2-Nitrobenzoic acid: N,N-Dimethyl-...
3
votes
0answers
52 views

What's the chemical reaction between NaOCl and Brilliant Blue dye?

Based on my research NaOCl dissociates into Na+ and OCl-. Looking at the photo, how does the OCl- ion and the brilliant blue dye structure end up as the product? How does the OH attach itself to the ...
0
votes
0answers
25 views

What is the condensed formula for cyclohexane? [duplicate]

I can't find it written anywhere and my guess is that it doesn't exist as it would be impossible to write it out in a straight line. Could $\ce{CH2CH2CH2CH2CH2CH2}$ be used ?
3
votes
0answers
26 views

Frontier orbital analysis of zinc-catalysed carbonyl-ene reaction

Q1. Is the $\sigma_\ce{C-H}$ bond a donor in this reaction? If not, then can we take the alternate combination (HOMO of alkene, LUMO of the $\ce{C-H}$ bond and, HOMO of the carbonyl)? Q2. We can also ...
2
votes
1answer
30 views

Regioselective enolate formation, choosing major and minor products

This question came in my organic chem assignment. The options highlighted are the answers. The end carbon(adjacent to the carbonyl group) should have more acidic alpha-hydrogen and the alkene formed ...
0
votes
0answers
28 views

What is the proper use of the term “pi-donor ligand”?

Robert Crabtree's The Organometallic Chemistry of the Transition Metals (7e) describes a pi-donor ligand as being a pi-donor "as a result of the lone pairs that are left after one lone pair has ...
2
votes
1answer
39 views

EDTA sedimentation problem?

I tried to create a suspension of EDTA powder in Glycerin with 1:1 ratio. I keep facing problem of EDTA sedimentation. I've tried other ratios also but this was the only one which formed least amount ...
0
votes
0answers
28 views

N-hydroxysuccinimide as a good leaving group

In the synthesis of carboxylic acid derivatives (esters, amides), I often see N-hydroxysuccinimide used in conjunction with a coupling reagent (EDC, DCC). The reason given for this (from online) is ...
1
vote
0answers
26 views

Would the initial step of this mechanism be exothermic or endothermic? (Protonation)

My understanding is that since an O-H bond is being formed, the protonation step must be exothermic because energy is released upon bond formation. However, if I were to draw an energy/reaction ...
0
votes
0answers
41 views

How reliable is spectrometry in the determination of the oldest material Startdust?

After reading one of the latest findings by scientists, Stardust was considered the oldest material on earth. However having not much of an experience with chemistry, I was intrigued upon how ...
3
votes
2answers
79 views

How is 4H‐1,4‐oxazocine aromatic?

I’ve found 4H‐1,4‐oxazocine in my chemistry book and I’m perplex as it states as aromatic: I can count 6 electrons on p orbitals which could satisfy Hückel’s $n = 1,$ but the oxygen is sp3-hybridized....
1
vote
0answers
18 views

Which is more reactive in E1, benzyl or allyl

I'm don't know the english terminology for chemistry so sorry for probably butchering some terms. My question is, which of these is more reactive in an E1 reaction: The bottom two are the ...
3
votes
1answer
102 views

Why are isomers of parathion less active acetylcholinesterase inhibitors than paraoxon?

Parathion itself has been found to be a very weak inhibitor of acetylcholinesterase. It normally requires metabolic activation and the conversion into paraoxon in the body to actually start exhibiting ...
1
vote
0answers
40 views

What is the role of imidazole in the Appel Reaction with iodine (I2)? Why are other bases not used?

I presume the role is to soak up the HI that is formed. Why not other bases such as triethylamine? Is this because the quaternary ammonium salt could be formed? Would other non-nucleophilic or ...
1
vote
1answer
42 views

Why does the pH of a weak acid not increase by 1 when diluted by a factor of 10? [closed]

Strong acid pH increases by one unit when diluted by a factor of 10, but why do weak acids not?
0
votes
1answer
85 views

Why is 11-oxabicyclo(4.4.1)undeca-1,3,5,7,9-pentaene aromatic?

I have been told by my instructors that for a compound to be aromatic, it must be planar. In this given molecule the oxygen seems to be out of the plane of the conjugated system: how can it still be ...
0
votes
0answers
42 views

IUPAC Nomenclature for cyclic compounds without principal functional group [duplicate]

I am struggling naming cyclic compounds with multiple substituents and no principle functional group . If anyone can please elaborate the rules, it would be appreciated.
0
votes
0answers
14 views

Reasoning for as to which compound would undergo $\ce{S_{N} Ar}$ mechanism more quickly [duplicate]

Above are 2 compounds (p)-chloronitrobenzene and (p)-fluoronitrobenzene. So if both of the compounds were to undergo $\ce{S_{N}Ar}$ mechanism, according to me the (p)-fluoronitrobenzene should do it ...