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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Reactions of alkynes and Sodium or soda amide [on hold]

What happens when alkynes react with Sodium or soda amide? Does it liberate hydrogen so does it prove that alkynes are acidic? What happens when But-1-yne and but-2-yne react with Sodium and soda ...
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44 views

Can Hydride Shift and Methyl shift happen one after another in a carbocation?

Can hydride shift be followed by methyl shift for stabilizing a carbocation? In case both is possible which will occur first?
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40 views

Reduction of amide with LiAlH4

In reduction of carboxylic acid with $\ce{LiAlH_4}$ the first step is deprotonation. But in the mechanism of reduction of amide with $\ce{LiAlH_4}$ (here), the first step is addition of hydride on ...
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77 views

Comparing SN2 reaction rates

I've read in book that the main factor for determining SN2 reaction rate is steric hindrance. The lesser it is the faster the reaction. So consider this question: As you can see , it is a question ...
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Why does the OAc group leave in the first step of Oxymercuration?

The above picture shows the first step of Oxymercuration. The electrons attack the Mercury atom but the OAc group leaves. Why is this? Hg is a transition metal with a number of available oxidation ...
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48 views

Reverse Friedel-Crafts mechanism

I need to find a mechanism for the above reaction but I cannot make much progress. I do have something in mind but it doesn't seem entirely plausible: First the tert-butyl group leaves (this seems ...
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189 views

Chlorosulfonation mechanism

The above reaction looks very similar to a conventional sulfonation reaction but if the reaction pathway is analogous to sulfonation I do not see how the $\ce{SO_2Cl^+}$ would form. Surely ...
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83 views

Mechanism of styrene dimerization

I am struggling to find a mechanism for the above reaction. So far I have suggested that the proton adds to one of the reacting aromatic species leaving the resonance stabilized secondary cation. ...
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91 views

Why do E2 reactions (dehydrohalogenation) only occur when the hydrogen and leaving group are in the same plane?

E2 reactions (dehydrohalogenation) only occur when the hydrogen and leaving group are in the same plane. I can't think of a reason that they would need to be in the same plane, so what is the reason ...
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22 views

Ionize Hydrogen and Oxygen Gas in Electrolytic Cell?

As is well known, water can be electrolyzed into oxygen and hydrogen gasses. However, all redox reactions can be run in reverse. If I were to electrolyze water in 2 closed containers (in order to trap ...
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41 views

Is there a list of known rate laws for reactions?

I've been scouring the web for a website/pdf that lists reactions and their corresponding rate laws. Something like: \begin{align} \ce{A + B &-> C} & ...
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49 views

Fluorescein synthesis

What is the mechanism of the fluorescein synthesis performed by von Baeyer?
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61 views

Why does basic peroxide react via conjugate addition rather than through direct addition?

The following reaction occurs: The $\ce{HOO^{-}}$ ion reacts as a nucleophile at carbon number three and consequently the reaction is conjugate addition. However, Why would a peroxide not react ...
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Why aryl halides are very less reactive towards nucleophilic substitution reactions? [duplicate]

I've often herd that aryl halides are very less reactive towards nucleophilic substitution reactions. One of the reasons for this I found was that there is resonance effect in the compound, but how is ...
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92 views

Identifying rearrangement reaction?

I was asked to solve this problem, and the answer key shows this: I'm not sure what's going on here, but it looks like some sort of a rearrangement and reduction. Is it an internal reaction between ...
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19 views

Methylene Blue Photo-initiation PH

I am working on a project using methylene blue as photo-initiator for a polymerization reaction. In this classic reaction methylene blue will get reduced into leuco-methylene blue in presence of some ...
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39 views

Why does phosphorus tribromide act as a Lewis acid (electron acceptor)?

This question is purely out of curiosity and to help me remember the "why" of a mechanism to help me remember the "what/how". In organic chemistry we recently studied the Sn2 Substitution of Primary ...
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1answer
46 views

Why, during aspirin synthesis in acidic conditions, anydride carbonyl oxygen is protonated rather than salicylic acid carbonyl oxygen ?

The common route for aspirin synthesis (described here) employs acetic anhydride and salicylic acid, in acidic conditions. The first step of such a reaction mechanism is the protonation of the ...
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41 views

Attack of amine on amide

I am confused with the last step of clozapine synthesis: How can the amine group attack the amide group to form the amidine in such acidic environment? Is the intermolecular reaction between an ...
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202 views

What is the major product on chlorination of 2-methylbutane?

I came across a question asking for the major product on chlorination of 2-methylbutane. The answer in the back of the book says it will be 2-chloro-3-methylbutane. However, I thought the major ...
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87 views

Amine addition to nitro group

What is the mechanisms of this reaction? How feasible is this reaction? Can it happen under not too much vigorous conditions if it were intermolecular?
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116 views

What will be the major product on chlorination of m-nitrophenol?

I came across a question asking for the major product on chlorination of m-nitrophenol. In my opinion the deactivating nature of nitro group should control the regioselectivity, but I found out the ...
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1answer
40 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 ...
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42 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. ...
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76 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?
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42 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 ...
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2answers
41 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 ...
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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 ...
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32 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 ...
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99 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 ...
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123 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 ...
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48 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 ...
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68 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 ...
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45 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 ...
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86 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 ...
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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 ...
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2answers
35 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 ...
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1answer
30 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 ...
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35 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 ...
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114 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 ...
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53 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 ...
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55 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 ...
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2answers
276 views

Determine the Value and Units of the Rate Constant

Consider this initial-rate data at a certain temperature for the reaction described by $$\ce{2NOBr(g) \rightarrow 2NO(g) + Br2(g)}$$ ...
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232 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?
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43 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 ...
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351 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. ...
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105 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 ...
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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 ...
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98 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?
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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 ...