The step by step sequence of elementary reactions by which overall chemical change occurs.

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CuCl after ignition to form Cu + CuOH complete formula? [on hold]

I'm doing an assessment for Pre-Uni and its about firework colours with chemistry, The only problem I'm having is that After ignition CuCl (Blue Flame) with form CuO + CuOH which will result in a ...
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26 views

Concerted hydride and alkyl shifts

I noticed while looking through a couple of books (specifically, Wade, Carey, and Vollhardt/Schore) that the mechanism of concerted hydride and alkyl shifts is always shown with alcohol leaving ...
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1answer
35 views

Method of allylic and benzylic oxidation

I am told that $\ce{MnO_2}$ oxidizes allylic and benzylic alcohols. However, what is the mechanism of this oxidation? All the professor had to offer me was that the metal ion, manganese 2+, chelates ...
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32 views

Free rotation of sigma bonds; diastereomer formation; thermodynamic and kinetic products

For the reaction of 1,3-butadiene with DBr (D = heavy hydrogen), I found that several possible products could be formed. Kinetic products A pair of enantiomers is formed. One of the pi bonds ...
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32 views

Sodium metal reduction of chloroform

In discussing how best to deuterate chloroform, it occurred to me that we could use sodium metal to reduce hydrogen into hydrogen gas. If this could actually happen, this would be a great thing - we ...
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58 views

Hydrogen and deuterium exchange

Is this a valid mechanism? I think it is. It is just a simple acid base mechanism. Could I increase yield though by using a stronger base than heavy water? Perhaps heavy sodium hydroxide? Or is ...
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31 views

The instability of hydrated carbon dioxide or “carbonic acid”

Why is hydrated carbon dioxide - the predominant form of acid that one gets upon dissolution of carbon dioxide in solution - so unstable? Is the below rationale valid? Carbon in carbon dioxide has ...
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2answers
59 views

Synthesis of 1-hexene from 1-octyne

This is my synthetic pathway. For one, is it plausible? For another, is it efficient? 1) Reduction of 1-octyne with hydrogen gas and Lindlar's catalyst to 1-octene. 2) Oxymercuration to install a ...
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70 views

2-methylpropene to tert-butyl alcohol Reaction Mechanism

Can someone explain what reaction is going on here? I looked in my list of mechanisms learnt: I find nothing related!
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47 views

Regioselectivity of Birch reduction (electron donating groups)

Why does Birch reduction on benzene derivatives with an electron donating group happen at ortho and meta positions? When the substitute is electron withdrawing, ipso and para reduction take place ...
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+50

Can in any case the faster step of the reaction be rate determining?

I found a sentence in book which states the reverse step of this reaction ( I forgot what was it!) has the faster step as rate determining . Even Rate determining step-Wikipedia states: In ...
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216 views

Carbon decrease from 1-octyne to 1-hexene

I am to turn 1-octyne to 1-hexene. Method 1 1) Reduction using sodium metal in pure ammonia to an alkene. 2) Halohydrin formation; the -OH installs at the more substituted carbon due to its ...
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28 views

What reaction is expectable from the atomized reactants?

Let we have a reaction that starts from some reactants to produce some products. When the activation energy is provided to the reactants they will be atomized and produce a gas of individual atoms. ...
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48 views

Deamination of Spermidine?

I was making a solution of spermidine, and noticed that Sigma Aldrich warns that spermidine solutions deaminate over time. I tried to think of how that would happen, and made a diagram: Assuming ...
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1answer
73 views

Nitrosation of benzene

How does benzene react with $\ce{NaNO2/HCl}$? Will $\ce{PhNO}$ be obtained? I read that pyridine can be produced under special conditions, but what will happen in some less exotic conditions?
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55 views

Is this the correct mechanism of the formation of the nitronium (NO2+) ion from sodium nitrate and sulfuric acid?

I am currently working on a mechanism for forming paracetamol (or N-(4-hydroxyphenyl)-ethanamide). The typical reaction to nitrate the phenol (starting product) is $\ce{NaNo3}$ with a catalyst of ...
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454 views

Pedagogical exercise - How to synthesize methamphetamine

I am asked to synthesize "methamphetamine." Note that there is no configuration designated for this molecule, and methamphetamine refers to a very specific configuration. In any case, here are the ...
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108 views

Bromination Pathways with alkane, alkene, and alkyne substrates

I'm confused about halogenation pathways. From what I understand, there are multiple halogenation pathways. I'll try summarizing them below; let me know if I do anything incorrectly. Halogenation ...
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100 views

Nitrobenzene reduction with (tin) Sn catalyst: Why is C-H bond cleavage preferred over O-H bond cleavage?

I am trying to understand this mechanism for nitrobenzene reduction with $\ce{Sn/HCl}$. I do not understand why it implies that you pull off the $\ce{C-H}$ hydrogen instead of the $\ce{O-H}$ hydrogen ...
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62 views

HI/P reduction mechanism

I recently answered a question about Breaking Bad's initial methamphetamine production method (i.e. the reduction of (pseudo)ephedrine). The reaction is as follows: (Source: ...
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58 views

Causes of reversible reaction

It is generally said that reactants react so that they can achieve a lower energy state. Then why does a reversible reaction occur in the first place? Since turning reactants into products increases ...
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1answer
82 views

How does sulfuric acid dehydrate sugars?

I know sugars have -OH groups, and that sulfuric acid is a strong acid. What I'm failing to see is how exactly sulfuric acid dehydrates sugars. Does it protonate the hydroxyl groups, making them good ...
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49 views

Nitration of Aromatic Compounds

I am told by Dr. Klein that in the nitration of benzene, hydrogen sulfate anion acts as the base and deprotonates the sigma complex. My question is why would the hydrogen sulfate anion be doing ...
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35 views

Benzene Halide Sn1 Reaction?

Is such a reaction possible? Will the benzene carbocation be stabilized via resonance? Suppose the leaving group is super electronegative and the environment is protic. What would be a suitable ...
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76 views

Why is the addition of a singlet carbene to an alkene stereospecific? [closed]

Why is the addition of a singlet carbene to an alkene stereospecific, but not when a triplet carbene is added?
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66 views

How to figure out if the reaction proceeds via SN1 or SN2 mechanism?

I have been assigned with the task of figuring out whether a reaction is $\ce{S_{N}1}$ or $\ce{S_{N}2}$. The information that I have is, that the yield is dependent on solvent polarity. More ...
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82 views

Acid catalysed mechanism of the addition of alcohols to alkenes

I believe that this mechanism is false. The protonated ether would in my opinion give a proton to methanol rather than $\ce{H2SO4}$ because the protonated $\ce{CH3OH}$ is more stable than ...
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47 views

Catalytic iodine in synthesis of phosphonium salts

From Clayden et al. However, iodine is expensive and a way round that problem is to use a catalytic amount of iodide. The next phosphonium salt is formed slowly from benzyl bromide but the ...
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33 views

Mercury vapor release from amalgam fillings

What would cause vapour release from elemental mercury? Would it be pressure, friction... could one stop the vapour release through cooling the mercury?
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1answer
44 views

2,2,6,6-Tetramethylpiperidine - Bronsted Basicity

I understand that this molecule can only act as a Bronsted base because it is sterically hindered by its multiple methyl groups. However, isn't the proton bound up in solution? Doesn't that ...
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35 views

Ethene to ethanol: electrophillic additions involving ethyl sulfates

http://www.chemguide.co.uk/mechanisms/eladd/symh2so4.html I was reading my textbook and this website. I just cannot find the mechanism for what happens when we go from CH3CH2OSO3H to ethanol by the ...
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95 views

Synthesis via Sn2/Sn1, E2, E1: Choice of solvent

I uploaded pictures on http://www.physicsforums.com/showthread.php?t=765106 I was looking at the answers in my textbook. They seem to make incongruent choices of solvents. In e) and j), why choose ...
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1answer
23 views

Reaction of alkyl halides with strong unhindered bases

Please look at the image on this website: http://www.physicsforums.com/showthread.php?t=765853 For (b) and (c), what the solution manual says makes no sense to me. You're reacting a primary alkyl ...
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19 views

Can anyone explain the reaction mechanisms of these synthesis?

Can anyone explain the reaction mechanism of the following synthesis ? 2NH4Cl + Ca(OH)2 --> 2NH3 + 2H2O + CaCl2 (NH4)2SO4 + 2NaOH --> 2NH3 + 2H2O + NaSO4
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66 views

Mechanism of reduction by elemental sodium

How exactly does sodium form an alkoxide from an alcohol? I understand the general idea - sodium has a low first ionization energy. Sodium can thus give up its electron to something that'll take it. ...
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30 views

Why does charcoal absorb smells from the air, and where do those smells 'go' once absorbed?

I've read that using blocks of charcoal can remove some odors from the air by placing them in the vicinity of the odors. (Maybe not as efficiently as other forms of carbon, as pointed out in the ...
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1answer
25 views

Converting cyclic compounds to linear compounds (possible ?)

Can one convert from cyclic convert to linear compound? Like $Cyclohexane$ $+$ $?=Hexane$ Even in High Temp and Pressure? I know it is very tough since we are going from a stable compound to a ...
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32 views

Reaction between FeCl3 and KI

FeCl3 + KI + H2SO4 = Is it necessary to have the medium acidified , in order to do reaction between FeCl3 and KI ?
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69 views

What is the result when the polarity of the solvent is increased in nucleophilic substitution?

I read in the Guidebook to Mechanism in Organic Chemistry that increasing the polarity of the solvent slightly reduces the rate of an $S_N2$ reaction. Why does this happen? Another question: We know ...
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3answers
50 views

How to determine order of nucleophilicity among commonly used nucleophiles?

For eg. In Finklestein reaction, NaI(reagent) taken in acetone(solvent) displaces SH(-) ion from alkyl group via SN2 mechanism to form alkyl iodide. But in a separate question we may be asked to write ...
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44 views

Acid “Catalysis”

I don't follow this reaction. This is after all an acid catalyzed dehydration reaction; why then, is the final product the alkene and water? Water wasn't the original acid. Hydronium ion is the ...
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1answer
94 views

Epoxide Ring Opening - Paradoxical Statement

I am told that the nucleophilic chloride anion attacks the tri-substituted location because it has the most partial positive character due to its ability to stabilize positive charge. How does that ...
2
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1answer
76 views

Cleavage of Ethers

Very confused by this video I stumbled across describing the cleavage of ethers with strong acids: From what I can gather, the cleavage of ethers is run in aqueous strong acids such as HI or HBr. ...
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63 views

Ring Formation and Alkenes

I was consulting Wade and I came across this problem and solution: While I agree with the solution manual, I can't help but wonder if my proposed mechanism is correct. I had the water attack ...
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1answer
73 views

SN1 Mechanism and Allylic and Benzylic Carbocations

My teacher stated that allylic carbocations are comparable in stability to tertiary carbocations. With this in mind I am confused why this MIT practice test states that these two molecules are only ...
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97 views

SN1 reaction of ethanol at tertiary alkyl halide

I know this undergoes an $\ce{S_{N}1}$ reaction: Ethanol is the solvent. Weak nucleophile. Neutral nucleophile. This points toward $\ce{S_{N}1/E1}$ (competing pathways). The leaving group is on a ...
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3answers
151 views

E2 Elimination; Anti-periplanar beta hydrogen

I'm confused by this picture I found online on a very popular organic chemistry website: (http://www.masterorganicchemistry.com/2012/10/10/comparing-the-e1-and-e2-reactions/) I agree that the ...
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82 views

Can anyone explain the reaction mechanism of these two synthesis?

Can anyone explain the reaction mechanism of the two synthesis given below ? $\ce{Ar-NO2 ->[\ce{H2/Pd}][\ce{EtOH}] Ar-NH2}$ $\ce{Ar-NO2 ->[\ce{Sn + HCl} \text{ or } \ce{Fe + HCl}] Ar-NH2}$
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40 views

Reaction mechanism of combustion of H2?

After a discussion about the usefulness of hydrogen fuel for cars with a friend of mine, I wondered what the reaction mechanism for combustion of $\ce{H}_2$ was. I only study (well almost) organic ...
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69 views

Difference between nickel catalyst and Raney nickel catalyst

Many times i have seen the catalyst as Raney nickel instead of nickel catalyst. I think Raney is a name of chemist who discovered Raney nickel catalyst.I think Raney nickel catalyst and nickel ...