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 ...

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263 views

Is there a simple and inexpensive way to generate nitrogen gas?

It's fairly easy to generate a significant yield of hydrogen gas simply by reacting zinc metal with $\ce{HCl}$ or aluminum with $\ce{NaOH}$ solution. But is there a simple and inexpensive chemical ...
7
votes
2answers
167 views

Why is gold unreactive when only one electron in outer shell?

I've been trying to answer my (high school) daughter's questions about the periodic table, and the reactivity series, but we keep hitting gaps in my knowledge. So I showed that the noble gases have a ...
1
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0answers
7 views

In which beta-elimination reaction do the structures of the carbocations formed influence the reactivity?

I believe there is a mistake. If we go back to the mechanisms, E2 does not go through a carbocation. So, there should not be any impact. E1 does however. So, E1 should be circled. Is there a ...
0
votes
1answer
12 views

Strong Base combined with Sp2 carbons in Nucleophilic Substitution and Beta-Elimination Reactions

When we are given this problem, there is a certain problem. We have a strong base, but hydrogen on the carbon of the phenyl. E2 is impossible. Also, SN2 is not possible since we have a hindered ...
0
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1answer
23 views

Can HBr add to a non-sp2 hybridized carbon?

Does this reaction make sense? Mechanistically speaking, it does not for me. Is this a special case, or just a typo in the book?
0
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0answers
39 views

Please explain the mechanism of Cannizzaro's reaction

I did not completely understand the mechanism of Cannizzaro's reaction, especially the rate determining step i.e. the hydride transfer step, and the effect of electron withdrawing substituents on this ...
1
vote
3answers
61 views

SN2 attack and sp2 carbons

Why can't an enolate anion successfully displace a halogen from a benzene? I am told that the geometry is incorrect; that such SN2 substitutions take place on sp3 hybridized (i.e. tetrahedral) ...
1
vote
2answers
39 views

Why is the halogenation of an alcohol a multistep process?

Refer to the mechanism posted on this site, if you will: http://www.chem.ucalgary.ca/courses/351/Carey5th/Ch08/ch8-10-3.html When the alcohol attacks the sulfur center, the pi electrons in the oxygen ...
4
votes
1answer
40 views

Carbocation rearrangement in alkene addition reaction

This is a question from my textbook: Determine a step-wise $S_N1$ mechanism for the overall reaction: The solution shows the following carbocation rearrangement after Bromine leaves in the ...
6
votes
3answers
75 views

Does radioactivity affect chemical reactions

Do compounds of radioactive elements show a bit different behaviour, and what happens when the radioactive part of the given compound decays, e.g, Radium Chloride, what happens to it when radium ...
2
votes
2answers
107 views

Endo rule for the Diels Alder stereoselectivity

Do you agree with the stereocenter with the CF3/CN in the product? source I would have expected that CF3 is a better electron withdrawing group than CN, and therefore placed opposite the diene and ...
2
votes
1answer
25 views

Concerted mechanism of saponification

The energetics of the mechanism of saponification were previously under debate, but I will admit, I misrepresented a point. Here is the revised mechanism of saponification proposed by someone other ...
5
votes
1answer
87 views

Significance of Proton Tunneling

It has been repeatedly emphasized that proton transfers "involving" three or four membered ring transition states are not favorable and should not be drawn as the primary mechanism for any reaction. ...
1
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2answers
61 views

Hydrolysis under basic conditions

Which route actually occurs? Is it really true that the carboxylic acid never forms under basic conditions? Why not just form the -COOH and deprotonate it afterward?? Or is there a higher activation ...
4
votes
1answer
43 views

What is the reaction mechanism of a 5-endo-trig cyclization?

I am trying to solve this mechanism for a disfavoured 5-endo-trig cyclisation to generate the disfavoured product (4) from starting material (1). The favoured 5-exo-trig is given by (2), which I have ...
0
votes
1answer
34 views

Using curved arrow notation to show electron movement in transformations

For each of the following transformations, use curved arrow notation (electronpushing) to show the movement of electrons. Show all formal charges. I'm not really sure how to approach the problem. I ...
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0answers
42 views

Could someone display the mechanism for the reaction of benzophenone with sodium borohydride?

I wondering about the details of the question like bonds broken/formed. As well, just general information on the reduction of ketones would be helpful.
0
votes
1answer
51 views

Why is nitration of veratrole specific in these positions?

Why do we not need $\ce{H2SO4}$ as acid catalyst for di-nitration of veratrole? Why does the 2nd nitro group go to positions 4 or 5, following the directing effects of the methoxy-group? Doesn't the ...
1
vote
1answer
38 views

Define “reactivity”

Does reactivity of a compound depend on kinetic factors, thermodynamic factors, or both? i.e. how is reactivity defined? For example, out of a) 2-bromopropane and b) 4-bromobutan-2-one, which is more ...
1
vote
2answers
74 views

Doubt in Cannizzaro reaction

My doubt is, how do we predict the products of a cross Cannizzaro disproportionation in presence of a concentrated base? Ie, How to judge which of the aldehydes (both don't have any alpha hydrogen) is ...
3
votes
1answer
30 views

Why do strong acids dissociate (almost) fully on a molecular level?

In the Brønsted-Lowry theory, strong acids $\ce{HA}$ dissociate using water and react into hydronium ions and the conjugate bases $\ce{A-}$. However I never understood in the strong acids case what ...
3
votes
1answer
52 views

Electrophilic aromatic substitution in heterocycles

I have a question from a past exam that i'm using to revise. I think the answer for part i/ii involves nucleophilic aromatic substitution with NH2- as the nucleophile. Part iii involves alkylation ...
1
vote
1answer
56 views

What would be the reaction:if I put melting iron in normal water?

I know it's a very ordinary question.But I have to know it correctly. What would be the reaction:if I put melting iron in normal water?Will water be chemically changed?
1
vote
1answer
49 views

SN1 Reaction Involving Carboxylic Acids

Which oxygen atom is more nucleophilic in carboxylic acids? If we look at this page, it says the carbonyl oxygen is more nucleophilic: However, I also learned in class that $\mathrm{sp^3}$ atoms are ...
2
votes
1answer
36 views

Why does in the hydrolysis of acetylsalicylic acid with NaOH the solution has to be simmered gently?

Why does in the hydrolysis of acetylsalicylic acid with NaOH the solution has to be simmered gently? What could happen if I would strongly boil it. Would the OH- react into the carboxyl groups to ...
1
vote
0answers
22 views

Devising a mechanism for reaction between Aluminium and Iodine

What should be a suitable mechanism for the reaction between Aluminium and Iodine, catalysed by water? In my initial approaches, I had first thought of repeated attacks of lone pairs of oxygen in ...
2
votes
2answers
85 views

MECHANISM 2 step reaction: bromination of alkene and then nucleophilic substitution

Write the mechanism for the following reaction: My answer so far: I have only shown one of the reactions, I presume it is the same for adding the other $\ce{Me2NH}$ on the other side. How do I ...
4
votes
2answers
145 views

How do I isolate calcium from calcium carbonate?

I have the ability to use many kinds of reactions, and the use of most common acids/bases.
4
votes
1answer
154 views

Dehydration of secondary alcohol reaction. (E1 Reaction)

I am trying to do a dehydration of an alcohol using the reagents sulfuric acid and acetic acid. I don't know how I am supposed to use the acetic acid, instead I've been using water. The question is, ...
1
vote
1answer
79 views

Synthesis of Pseudopelletierine, Mannich reaction base catalysed

The synthesis of Pseudopelletierine starts from glutardialdehyde, which reacts with methylamine and acetonedicarboxylic acid in a two-fold Mannich reaction. This is the reaction: I need to write ...
5
votes
1answer
62 views

Why doesn't rubidium react with nitrogen gas?

I ran across a problem in which I was asked to predict the result of a reaction between $\ce{Rb}$ and $\ce{N2}$. I was frustrated until I found a note in my textbook which stated that out of all the ...
-2
votes
1answer
30 views

Is (A->B<-C) a multi-step reaction?

I want to know if: A -> B <- C a multi-step reaction OR are multiple reactions: A -> B, C -> B
1
vote
1answer
51 views

Chemistry and mathematical modelling

I'm searching for a chemical daily life experience that can be modeled by superior mathematics so that the origin of the equations involved can be easily explained to a beginner in chemistry. By ...
3
votes
1answer
67 views

Formation of azobenzene from nitrosobenzene and N-hydroxyaniline

I'm trying to create a reasonable reaction mechanism for the reaction of nitrosobenzene and N-hydroxyaniline, which happens as part of the reduction of nitrobenzene to azobenzene using magnesium as ...
0
votes
1answer
34 views

Rgarding common preservatives and their effect?

If someone has an average of 1 litre of Coke or Pepsi a day would this form too much Benzene oxide in the person's body or stomach and eventually effect part of their genetics?
2
votes
1answer
44 views

Am I correctly showing a hydride shift on the alkyl halide?

I did this quiz and I forgot the hydride shift. With the hydride shift, would these be the right answer?
2
votes
2answers
87 views

SN2 vs SN1 in Acidic Environments for Secondary Alkyl Halides

I have researched three books: Brown's, Solomons' and Wade's. I could not find enough information about this. My prof. says that secondary alkly halides undergo SN1 only under acidic environments. ...
1
vote
1answer
46 views

Carbocation Rearrangements in SN1 reactions

Would one get 1-(1-chloroethyl)-1-methylcyclobutane? I am not sure if the driving force identification is correct? Is my going from a 2° to a 3° carbocation correct? Does anyone have any tips for ...
1
vote
2answers
43 views

Predict the Product(s) of a reaction of tertiary benzylic alkyl halide

I could find two products: The first one where is $\ce{Cl}$ is replaced by $\ce{CN}$. AND the second one where $\ce{CH3CH2O}$ replaces $\ce{Cl}$. Did I make a mistake or miss anyone?
4
votes
2answers
157 views

SN2 vs SN1 in Secondary Alkyl Halides

What would you have chosen as a mechanism? Would SN1 occur here? I chose SN2 because we have a secondary alkyl halide with a weak base $\ce{CN-}$. However, the solution says SN1 is major. Can you ...
1
vote
2answers
118 views

Reductive amination of (protected) 3-Oxopropanenitrile: Will azetidin-2-ol be formed via intramolecular ring closure?

What happens during this reductive amination? I got the first product; the lithium aluminium hydride will reduce the nitrile to an amine. But what about the reductive animation step? As far as I can ...
3
votes
6answers
136 views

“There are no chemical cliffs”

Are there any reactions with no activation energies? Prof just told us there are no chemical cliffs. Is this true? I read something about nuclear decay as being a reaction with no activation ...
4
votes
1answer
54 views

Osmium tetroxide and meta-chloroperoxybenzoic acid

Can these be used to induce acetal ring closures? For example, when dealing with a molecule that has both a C=O functional group and an alkene as part of its structure and there is the possibility of ...
0
votes
0answers
34 views

Imine stability in acids and bases

I understand that imines can be hydrolyzed in acidic medium. But what about in basic medium? Can imines still be hydrolyzed? I have a plausible mechanism ... nitrogen's withdrawal of electron ...
5
votes
1answer
71 views

What is the mechanism for demercuration?

The following image is from 'Organic Chemistry Second Edition' by Clayden, Greeves, and Warren. The final step is the demercuration, but I'm unable to find a definitive mechanism. The wikipedia ...
2
votes
1answer
46 views

Rate Expression for Reactions Involving 2° Benzylic Alkyl Halides

My teacher took off marks because he said the reaction was SN1. Before I go confront him, please tell me if my reasoning is correct. So, basically, I thought: we have two possibilities: 1. SN1: a ...
3
votes
1answer
69 views

NH2- and Primary Alkyl Halides: Sn2 vs E2

When we mix 1-bromopropane and $\ce{NaNH2}$, what happens? Which reactions wins out to make the major product? My textbook says that primary alkyl halides give mainly SN2 products unless the base is ...
3
votes
2answers
161 views

Why cant unimolecular reactions be 2nd order?

Why can't unimolecular reactions be second order? For example, doubling the concentration of a single reactant would result in four times the original rate of reaction.
2
votes
1answer
143 views

Acidic conditions, high heat, and return to carboxylic acids

Apparently carboxylic acid derivatives such as cyanohydrins can be taken back to "daddy" - a carboxylic acid - under the right conditions. This involves acid, water, and "high heat." What, however, is ...
0
votes
0answers
44 views

Relationship between Auto-Ignition Temperature with Pressure and Fuel

Experimentally it appears that increase in pressure, fuel concentration, and chain length causes AIT to decrease until a minimum where even further increase in these parameters increases the AIT. ...