The detailed and complete as possible description of plausible or observable pathways leading from reactants to products of a chemical process. This tag should be applied to questions, which seek information on elementary steps of these processes. It may be applied to hypothetical and/or proposed ...

learn more… | top users | synonyms (1)

1
vote
1answer
16 views

Aluminum deoxidation gas

I am new to chemistry. I am looking for a gas that would de-oxidise aluminium. Which gases would work for that and at what temperature? Details: I need to sinter aluminium powder. But because the ...
4
votes
1answer
28 views

How does NMO reform Osmium tetroxide after reaction with an alkene?

After Osmium tetroxide adds to a double bond and is then hydrolysed the following species is formed: Because Osmium tetroxide is toxic, NMO is used to transform the above back to Osmium tetroxide. ...
4
votes
1answer
71 views

Ozonolysis of nitronate

What is the mechanism for the ozonolysis of a nitronate anion? What gas is produced in this reaction? Is there any chemoselectivity in the presence of a double C=C bond in the molecule?
0
votes
1answer
40 views

Intramolecular hydrazide condensation

Say I have the compound $\ce{CH3CONHNH2}$. Is it possible, that when I add an acid, an intramolecular condensation reaction occurs, forming the cyclic compound: Furthermore, in general, the ...
4
votes
2answers
37 views

Is water a better nucleophile than bromide?

I am a student of biochemistry. My organic chemistry professor was giving a lecture and he talked about halohydrin formation reactions. At one point, he said that "water attacks instead of bromide ...
2
votes
1answer
38 views

Why don't water molecules react alongside aqueous reactions?

To explain my question I'll use an example: We all know that sodium displaces copper in a solution of its sulfate in the reaction: $$\ce{2Na (s) + CuSO4 (aq) \rightarrow Na2SO4 (aq) + Cu (s)}$$ My ...
2
votes
1answer
22 views

Cannizaro Reaction, Hydride Shift Reason?

In Cannizaro reaction when concentration of OH- is less in the rds step hydride shift occurs, though it is very difficult for hydride ion to shift yet the reaction proceeds but what is the driving ...
7
votes
1answer
88 views

Why is SN2 favored greatly over SN2'

Secondary allyilic halides can be produced in high yield with the following Mitsunobu type reaction: The yield being 94%. The last step in the mechanism is: Why is the $S_N2$ reaction so much ...
6
votes
1answer
115 views

Does fluorescein decompose from long term exposure to light?

I've had about one liter of fluorescein solution setting on the shelf for at least several years and one day noticed that it suddenly lost its characteristic green color. It's now a light ...
5
votes
1answer
45 views

If Alkynes can be reduced to Alkenes using Sodium in liquid ammonia, why can't Alkenes be reduced to Alkanes?

Firstly, I would like to ask why the alkyne reacts at all with the solvated electron? Surely the alkyne group is extremely nucleophilic (more so than the alkene). This, to me, seems to suggest that ...
3
votes
2answers
56 views

Why is ozone an electrophile in the ozonolysis reaction?

From the above mechanism it is clear to see that the electrons from the double bond attack one of the terminal oxygens in ozone, thus meaning it's an electrophile. How can this be? If you draw the ...
2
votes
1answer
37 views

Reduction of amides

The reduction of an amide using LAH yields a primary amine . I looked up the mechanism over here. The mechanism suggests that the final main product (amine) is produced before giving the products a ...
3
votes
1answer
64 views

Thionyl Chloride and enols, carboxylic acids, alcohols

Propanol + SOCl2 -> Expected alkyl halide product. Propanoic acid + SOCl2 -> Expected acid chloride product. Acetone enol + SOCl2 -> doesn't work in the expected manner. My prof says the SOCl2 ...
1
vote
0answers
41 views

What is Barrier-less reaction in Quantum Chemistry?

After finding a reaction "Transitional State " by GAMESS and finding Hessian Eigenvalues, my project instructor said: " seems your imaginary frequency ( negative eigenvalue ) is not that big ( it is ...
2
votes
2answers
30 views

Best ways to start a thermite reaction?

I'm trying to do a thermite reaction with rust and aluminum and am trying to figure out the optimal way to get the reaction started. My understanding is that I need a temperature of around 3200F to ...
2
votes
1answer
25 views

What are Solvolytic displacement reactions?

High school student here, I recently purchased a book titled : "Solvolytic Displacement Reactions" by Andrew Streitwieser published in the early 1960's. I found it at a book store and it looks like ...
3
votes
1answer
29 views

Why does the opening of an epoxide occur via an Sn2 like mechanism when using a methanoate ion as a nucleophile and methanol as a solvent?

Below is a picture of the mechanism: I understand the mechanism but what I don't understand is why it's $\mathrm{S_N2}$. The solvent used is polar and protic, there is a tertiary carbon that would ...
9
votes
1answer
107 views

Can magnetic fields affect a chemical reaction?

This question was asked recently in an interview and I just said that "Yeah, like if the reaction involves ions or paramagnetic species". But the interviewer went on and asked me to elaborate on HOW ...
0
votes
1answer
50 views

Can anyone explain the reaction mechanisms involved in the following organic chemical reactions?

$$\ce{R-OH + NaBr + H2SO4 \rightarrow R-Br + NaHSO4 + H2O}$$ $$\ce{R-OH + PCl5 \rightarrow R-Cl + POCl3 + HCl}$$ $$\ce{R-OH} \text{(in presence of red P/[} \ce{Br2} \text{ or }\ce{I2} ]) \rightarrow ...
0
votes
2answers
46 views

What causes hydrogen abstraction in the radical chain mechanism?

In the first propagation step of the radical chain mechanism, why does the halogen actually abstract hydrogen from the alkane? My ochem textbook so far has went into details on MOs, hybridized ...
1
vote
2answers
157 views

Determine the Value and Units of the Rate Constant

Consider this initial-rate data at a certain temperature for the reaction described by $$\ce{2NOBr(g) \rightarrow 2NO(g) + Br2(g)}$$ ...
9
votes
3answers
178 views

Why is pyridine used when making tosyl esters from alcohols?

Tosyl chloride is used to make a hydroxyl group into a better leaving group. However, when the reactions of tosyl chloride and an alcohol occurs, a weak base such as pyridine should be used. Why?
1
vote
1answer
41 views

Reaction Mechanism Of a 3 Step Reaction

A reaction is specified as having a fast step, then a slow step, then another fast step. Which of the four reaction mechanisms does this fall under? I believe it is a case 2 (fast then slow) because ...
7
votes
2answers
280 views

What are the products of the reaction of 1-methoxycyclohexene with dilute hydrochloric acid?

I am struggling with the following question in my problem sheet: "When 1-methoxycyclohexene is treated with dilute aqueous hydrochloric acid, methanol is produced along with another organic product. ...
5
votes
3answers
85 views

Dehydration of methylcyclobutanol

In one of the exams I saw it was written that dehydration of 1-methyl-cyclobutanol yields cyclobutylmethylene (double bond outside the ring) which is the anti Zaitzev product, instead of ...
3
votes
1answer
44 views

Saytzev and Hofmann elimination in E1

From what I have read, E1 largely produces the more substituted alkene because of the fact that more substituted alkenes are more stable as a result of hyperconjugation. However, in E2 the situation ...
3
votes
1answer
73 views

Why must the leaving group in E1cb be poor?

Typically the leaving group for E1cb is poor (like -OH or -OR) but why must this be the case? The substrate appears in the rate equation so surely a good leaving group would be beneficial?
4
votes
3answers
126 views

Making three membered ring using different reactants

I am struggling with the above question. It will be the conjugate base of trichloromethane that is involved. The same is true of the carboxylate. However, I have no idea about the reaction ...
3
votes
1answer
34 views

What is an example of a very low temperature endothermic reaction?

Shakashiri describes the reaction of solid Ammonium Thiocyanate and solid Barium Hydroxide Octahydrate resulting in an endothermic reaction leading to subzero temperatures. I've performed this ...
3
votes
2answers
129 views

reference states for activities

I wanted to ask clarifications about a passage in Atkin's physical chemistry book, chapter 9, in the paragraph 9.2 description of equilibrium. For studying equilibrium of a reaction, where $\nu_i$ ...
1
vote
1answer
57 views

How does HF Dissolve glass

I searched throughout Web but could not find or precisely relate anything to my question .I mean by what mechanism does it(HF) proceed in dissolving or rather disintegrating glass is it because of ...
2
votes
1answer
113 views

Elimination in dibromocinnamic acid

The above is a picture of dibromocinnamic acid. In the lab today I carried out an elimination reaction on this molecule using potassium carbonate giving the carbonate anion as a base. I thought ...
3
votes
1answer
53 views

Why does one bicyclic diastereomer react faster than the other one?

I have a difficult question in my problem sheet that I cannot solve. I have been asked to explain the following observation: I have a number of issues with this: 1) The fast reaction must be a ...
2
votes
1answer
33 views

Why can syn-periplanar E2 elimination happen in molecules like vinyl bromides but seemingly not in other molecules?

E2 eliminations occur when the leaving group and the proton are in the anti-periplanar conformation not syn-periplanar. This is beyond a merely a preference as leads to E2 reactions being ...
2
votes
0answers
19 views

Required HLB on the Griffin Scale

What is the required HLB on the Griffin Scale of 94% water and 6% mineral oil for producing a stable micro-emulsion?
0
votes
1answer
42 views

The standard for drinking water is 1300 mg/l and the first area has a value of 837 ug

I am trying to figure out the hazard quotient of copper compared to the standard. The standard for drinking water is $1300 \frac{mg}{l}$ and the first area has a value of $837 \mu g$. How do I convert ...
1
vote
2answers
58 views

Organic chemistry - alkanes step up reaction

Well I was studying organic chemistry, and I came across this reaction for increasing the length of the carbon chain. Upon asking my teacher about the following reaction, she said she was unsure about ...
2
votes
0answers
53 views

Woodward Hoffmann rules for electrocyclic reactions

For the thermal electrocyclic cleavage of cyclobutene to 1,3-butadiene, what is the correct assignment of the orbital components ? My attempt: I know this reaction is allowed (4n thermal ...
4
votes
1answer
66 views

In the elementary steps of a reaction, why do we assume that the coefficients of a reactant corresponds to its order?

Recently, I was taught that the coefficients of the reactants in an elementary step of a reaction indicates that reactant's order. Why is this the case? I thought that the order of a reactant was not ...
1
vote
1answer
38 views

Comparing adamantane carbon types for accepting OH using MM ForceField

I want to compare two type of carbons accepting OH in adamantane which I've shown below. I know the blue position is preferred. But I wanna prove it with energy optimization and MM Forcefield. I ...
0
votes
0answers
29 views

Reducing NOx with Ammonia. Practical in a gasifier?

Sorry if this is an outright stupid question. I am no chemist... For Nitric Oxide: $2{NH_{3}} + 2 NO => 2 {N_{2}} + {H_{2}} + 2{H_{2}O}$ For Nitrogen Dioxide: $2{NH_{3}} + 2{NO_{2}} => ...
1
vote
1answer
45 views

What is the difference between “reaction pathway” and “reaction mechanism”?

What is the difference between "reaction pathway" and "reaction mechanism"? Are these expressions synonyms? Some textbooks authors use both without making clear to the learner if they are synonyms ...
7
votes
0answers
113 views

Mechanism of dehydrogenation with Nosylate

What is the mechanism of the attached reaction? How could nosylate do the dehydrogenation? The reaction is from this synthesis (46th IChO preparatory problem 26):
3
votes
1answer
39 views

What is the mechanism for the creation of P(CH2OH)4+ cation?

I know that the initial reactants are phosphine and menthanal in an acid ($\ce{H+ A-}$) and that the first step in the reaction is the HOMO of phosphine (the lone pairs) and the LUMO of methanal (the ...
1
vote
1answer
169 views

How to solve an Arrhenius equation problem?

A widely used rule-of-thumb for the temperature dependence of a reaction rate is that a ten degree rise in the temperature approximately doubles the rate. This is not generally true, especially when a ...
3
votes
1answer
83 views

Elimination of bromide and acetate under reducing conditions

Here is the reaction that I didn't find the mechanism of; maybe you can help: The conditions is zinc dist, when the solvent is acetic acid at 110°C 1h. the reagents are Sodium acetate, ...
1
vote
0answers
60 views

How are catalysts discovered for a particular reaction?

I want to understand how are catalysts discovered for a particular chemical reactions say for example $\ce{Fe,~Mo}$ for Haber's Process reaction of $\ce{N2}$ & $\ce{H2}$. Reactions as examples ...
2
votes
1answer
39 views

Mathematical Statistics and Chemistry

I'm currently working towards a major in both chemistry and mathematical statistics as a part of my science degree, and I got to wondering: How will these two go hand in hand and help each other? ...
1
vote
1answer
114 views

Friedel-Crafts Alkylation Using Alkenes: Mechanism

What is the mechanism by which benzene, cyclohexene and $\ce{AlCl3}$ form cyclohexylbenzene? I believe that cyclohexene will form a bond with Al with its double bond. However, how do we get rid of ...
1
vote
1answer
24 views

In E1 reactions, does carbocation stability have impact on the final product?

In this question, I believe there is a mistake for iii). I think that there the tertiary carbocation would be formed (more stable), which would lead to the tetra substituted alkene (even more ...