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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What effect would di-ammonium phosphate have on glass production

Di-ammonium phosphate (DAP) burns off at approximately 300 degrees. The production of glass (with the help of soda ash) is approximately 6 times higher in temperature. What effect would DAP have on ...
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39 views

Problem in IPSO-substitution

Please clarify why ipso-substitution occurs only in secondary alcohol with thionyl chloride during SNi mechanism or is it whole different thing.I cant understand this mechanism quite clearly.And why ...
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19 views

Experiment used to distinguish radical and pericyclic reactions

In Oxford Primer: Pericyclic Reactions by Ian Fleming it is written that the deuterium substitution of the hydrogen atoms in the diene and dienophile that participate in a possibly ...
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14 views

Physic-particle accelerators, chemistry-? [on hold]

Lhc in cern is large machinery that studies about particle physics and can be used to synthesis new elements and all. But for chemistry there isn't such machines. Can we make new machines that can ...
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1answer
22 views

How does common salt speed up the setting of the plaster of Paris?

We use plaster of Paris (POP) to cast and lift foot prints/tyre prints from the crime scene for evidence purpose. While preparing cast, we follow standardized protocol and add a pinch of common salt ...
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0answers
25 views

Internal cannizzaro reaction

The compound $\ce{PhCOCHO}$ can undergoe both internal cannizzaro reaction and between two molecules. The internal cannizzaro reaction is like this: Which reaction will be preferred? Internal ...
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1answer
26 views

Explain the difference in stability of permanganate ions in acidic/ alkaline solutions?

The question is such: I know that the permanganate ion is more stable in alkaline solution than in acidic solution, as the more positive electrode potential in acidic solution means more negative ...
3
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2answers
83 views

Pyridine & Dichloromethane

I have a questions about the reactions pictured below. From my understanding, the first reaction replaces the $\ce{-OH}$ group with $\ce{-Cl}$. What role do pyridine and $\ce{CH2Cl2}$ play in the ...
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28 views

Corey-Seebach reaction regioselectivity

Does Corey-Seebach reaction with conjugated enones undergo in a direct or conjugated fashion? Can the two sulfur atoms soften the carbanion enough for it to undergo conjugated addition? If not, ...
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1answer
30 views

How chemical bonds are broken during chemical change? [on hold]

We know that during a chemical change, old bonds are broken and new bonds are formed.Is there a way to predict from where the bond will break and hence form products.
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1answer
17 views

periodic table and reactions [on hold]

Mancunium reacts violently with water to form a colourless gas and an alkaline solution. The alkaline solution is mancunium hydroxide with formula MOH. Mancunium also forms a chloride salt with ...
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15 views

Migration of R group in Hofmann rearrangement

In the mechanism of Hofmann rearrangement, one step involves migration of $R-$ group from carbon to nitrogen as shown: This reaction proceeds even if the migratory aptitude of the $R$ group is poor ...
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1answer
30 views

Hydrolysis of vinyl silanes

Alkynyl silanes can be easily hydrolyzed with TBAF like in the last step in the synthesis: How feasible is the hydrolysis of vinyl silanes with TBAF? Does it actually happen or some other routine ...
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35 views

Hiyama vs Sonogashira coupling

Why is Sonogashira's coupling more feasible than Hiyama's coupling when both could occur? I have seen many examples in syntheses, here is one (the penultimate reaction):
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44 views

Kinetic Isotopic Effect in EAS

It is observed that rate of reaction of two isotopologues of benzene, $\cf{C6D6}$ and $\cf{C6H6}$, is the same for electrophilic aromatic reactions, as the deprotonation is not the rate limiting step. ...
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0answers
31 views

Mechanism of acid Catalysed Sodium Bisulfite adduct [closed]

I have a reaction written in my textbook, which I can't understand. $$\ce{RR'C(OH)(SO3Na) ->[\text{Hydrolysis}][\Delta,~dil.~\ce{HCl}] RR'CO + NaCl + SO2 + H2O}$$ Why this reaction is ...
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how to find out the velocity constant of ethyl acetate catalysed by acetic acid practically in lab using reagents and equioments? [closed]

how to find out the velocity constant of ethyl acetate catalyzed by acetic acid using practical data in laboratory and how to gain and proceed with the readings ?
3
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2answers
41 views

What decides whether a reaction releases light or heat

I understand the reason that a chemical reaction would create photons (physics is more my strong point), but why would it create heat instead? My only guess is that the light released somehow causes ...
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0answers
18 views

Determining the type of electrocyclic via MO theory

I have been working on this particular problem for a while now to determine how this particular reaction plays out. I think it is a a thermo electrocyclic ring transformation involving 6 pi ...
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0answers
31 views

How the chemical reaction is happening? [duplicate]

I have got this IMAGE peculiar chemical reaction and tried to find reason behind it. But I couldn't. Can you write the reason?
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0answers
13 views

Chemical energy + energy of electrons

The amount of energy released in a chemical reaction is equal to variation of the enthalpy of this system (In general). The energy released is usually is in form of light and heat. When light is ...
3
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1answer
54 views

Corey-Schmidt oxidation of primary alcohols

Why does pyridinium dichromate (PDC) in dimethylformamide (DMF) oxidize alcohols to acids while in methylene chloride the oxidation stops at the aldehyde level?
3
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1answer
62 views

Nucleophilic substitution mechanisms in aromatic compounds

I was reading nucleophilic substitution in Aromatic halides and it suggests two different mechanisms namely - SNAr and benzyne mechanism. However, I am confused between which one to use when trying to ...
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1answer
109 views

Preparation of picric acid

My textbook says "Nowadays picric acid is prepared by treating phenol first with concentrated sulphuric acid which converts it to phenol-2,4-disulphuric acid and then with concentrated nitric acid to ...
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0answers
36 views

Determining Reaction Mechanism of Reaction

a) 2-bromo-3-phenylbutane reacts with $\ce{NaOMe}$ in methanol. What is the mechanism? b) this compound then reacted with $\ce{CN}$ in DMSO. What is the mechanism? Question 1 I am debating ...
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22 views

Why do SN1 reactions happen slowly?

'The first step where the carbonium ion forms is slow and because it contains only the halogen, the general speed of the reaction will be slow.' I don't understand why should SN1 reactions ...
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28 views

Is an ethyl shift possible in the reaction of 2-chloro-N,N-diethylbutan-1-amine with an hydroxyl ion?

What is the major product of the following reaction? $$\ce{(CH3CH2)2N-CH2-CHCl-CH2CH3 ->C[{}^{-}OH]}\qquad ?$$ Please see the option of problem 3 in the image below: My initial thought was ...
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0answers
37 views

Conversion of 1,2-dione to a 7 membered oxepane?

Has anyone heard of forming a seven membered ring from the rearrangement of a 1,2-dione? What I am talking about specifically is benzil rearrangement: Could anyone give me guidance for how on earth ...
3
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1answer
61 views

SN1 vs SN2 in low concentration of nucleophile

Why is SN1 mechanism favoured by low concentration of nucleophilic reagent? It is a first order reaction so shouldn't the reagent be in excess? Also higher the concentration of reagent faster the ...
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57 views

Enolate formation in cis/trans decalin

What will happen in the following reactions? I thought that after OH is converted into a good leaving group OTs, an enolate would be formed which would attack $CH_2OTs$, but the obtained structure ...
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1answer
50 views

What makes these particles hygroscopic? [duplicate]

Hygroscopy is the ability of a substance to attract and hold water molecules from the surrounding environment. For cotton there is capillary action. Hydrates like KOH attract water due to lower ...
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0answers
14 views

Is there a chemical reaction between tungsten carbide and acrylic?

My company machines acrylic (Poly(methyl methacrylate) (C5O2H8)n), and notices that tungsten carbide tools break down quickly compared to high-speed steel, even though carbide is harder and lasts ...
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0answers
15 views

How zerovalent Iron reacts with etylglycole?

In reaction of ethyl glycol and iron during anaerobic condition, on room temperature, reaction will not occur?
4
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1answer
74 views

Why phenanthrene can't undergo Diels-Alder reaction but anthracene can?

Why phenanthrene can't undergo Diels-Alder reaction but anthracene can? They seem to be structurally same (almost) with 3 aromatic rings and with active 9,10 positions. I can't understand. ...
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1answer
22 views

How can the formation of an alkene be explained during the hydrolysis of an ester when the alkoxy moiety is tertiary?

$$ \ce{RCOOR' + H2O -> RCOOH + R'OH} $$ But when $\ce{R'}=3^\circ$ it may result in the formation of alkene. But by the normal mechanism given in books and in various sites I am not able to explain ...
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96 views

Mechanism for reaction between hydrochloric acid and magnesium

Balanced equation: $$\ce{Mg(s) + 2HCl(aq) -> MgCl2(aq) + H2(g)}$$ However, Cl- is a spectator ion so the actual reaction equation is: $$\ce{Mg + 2H+ -> Mg^2+ + H2}$$ Here is my proposed ...
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69 views

Masamune's rule of diastereoselectivity multiplicity

In a reaction between a chiral substrate and chiral reagent, their asymmetric inductions could cooperate (matched pairs) or compete (mismatched pair). According to Masamune, in a matched pair the ...
3
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2answers
183 views

Why does the reduction of a Weinreb amide give an aldehyde instead of an amine?

The reduction of a regular amide with $\ce{LiAlH4}$ yields an amine. However, with a Weinreb amide, the product is an aldehyde. How can this be justified? I can't find the mechanism for the Weinreb ...
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2answers
134 views

Understanding the mechanism of Blanc chloromethylation

I have seen this question: Mechanism for chloromethylation of benzene. The answer there uses a picture from wikipedia which confuses me. It gives $$\ce{H2C=O <=>C[HCl] H2C+-OH <-> ...
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1answer
69 views

Why are 1,3-diols protected with aldehydes but 1,2-diols are protected with ketones?

1,3 diols are usually reacted with benzaldehyde when protection of the OH groups is desirable, but acetone is used when the relation between the hydroxyl groups is 1,2. Why is it so?
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How did this kind of reaction exihibit a sigmodal curve of product formation

A condenstation reaction between Ether and Aldehyde was performed under two-phase liquid system which the acidic aqueous solution was a catalyst phase. In the system, Ether and Water were excess. ...
3
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1answer
72 views

Mechanism for oxidation of primary alcohol to carboxylic acid

My teacher told me that the following is the mechanism for oxidation of primary alcohols to carboxylic acids: $\ce{Primary~alcohol ...
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0answers
41 views

What are all products of an ozonolysis of alkenes using zinc and water?

I'm studying ozonolysis reactions in alkenes, and saw that in one of them there is the formation of $\ce{H2O2}$ (Can anyone explain from where?) that I presumed that reacts with $\ce{Zn}$, one of the ...
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0answers
27 views

Determining Reaction Orders

Can you figure out the reactant's reaction order (First-order, second-order, third-order, etc.) JUST by looking at a chemical reaction? What if you were given a multi-step reaction? A single step ...
6
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1answer
97 views

Interchange of axial and equatorial groups in Me2NPF4

The $\ce{^{31}P}$ NMR spectrum of $\ce{Me2NPF4}$ when recorded at room temperature consists of a quintet with intensities $1:4:6:4:1$. However, at $-100~\mathrm{^\circ C}$, the spectrum is as shown ...
4
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1answer
51 views

1-5 dicarboxylic acid to lactone with SOCl2?

I came across a reaction whereby a 1-5 dicarboxylic acid is converted to lactone with $\ce{SOCl2}$. I was wondering what the mechanism of this was. I know that $\ce{SOCl2}$ converts carboxylic acids ...
2
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2answers
91 views

Self aldol condensation of butanal under basic conditions

The reaction is such: I've counted the number of carbons on each side: LHS=4, RHS=8 My working is such:
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1answer
171 views

The mechanism of demethylation of a quaternary ammonium

The problem is such: I know that the t-Bu locks the ring in equatorial position as I have drawn out: Could someone please point me in the right direction as how I can get rid of a Me in the NMe3+ ...
1
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1answer
69 views

Corey -House synthesis vs Wurtz reaction

In Corey House synthesis the first step is formation of Alkyl Lithium. why can't we react alkyl lithium with alkyl halide to produce alkanes. Rather we choose to prepare Gilman's reagent? Does it have ...
3
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2answers
59 views

How does this brominated intermediate lose its methyl group?

The problem is such: So far my working has been: I'm concerned about the last step where the ester forms a ring. The methyl group doesn't look like a plausible leaving group, but it does not ...