Questions tagged [organic-reduction]
For questions about reduction reactions in organic chemistry, where a molecule of interest is reduced. Do not use for questions on general redox concepts.
188
questions
0
votes
0
answers
26
views
Is this mechanism of reduction using LiAlH4 followed by hydrolysis of an amide correct?
Hello everyone. I had been given a question on reducing an amide group into an amine group using any reagent I saw fit as homework. I had used LiAlH4, which provides H- and does an acid base reaction ...
-2
votes
0
answers
105
views
Does H2, Pd/C reduce a conjugated ketone?
Would H2, Pd/C be a sufficient reagent for this reaction to proceed?
The question is from a test which asked what would be the most suitable reagent for the above reaction
2
votes
0
answers
66
views
What is the product and mechanism of reducing a cyclohexanone derrivative with LAH?
I've been trying to figure out the product and mechanism of the reaction pictured below for a while now:
I'm fairly sure that the first step is the reduction of the ketone by LAH, which results in a ...
- 29
3
votes
1
answer
72
views
Reduction of di-N-substituted imidazole to imidazoline to remove counterion?
I would like to synthesize a di-N-substituted imidazole (compound 4) in its free base form or reduce it to generate an imidazoline (compound 5) to remove the bromide counterion to the imidazole ring.
...
- 137
2
votes
0
answers
50
views
Reduction of benzylic alcohol and halide using H2 and Pd
I am studying drug synthesis, and I found some examples that uses $\ce{H_2}$ and Pd/C or Pd/$\ce{BaSO_4}$ as catalytic hydrogenation reagents for reduction of alcohol or halide in benzylic position. ...
- 993
1
vote
2
answers
324
views
What determines the location of nucleophilic attack on a conjugated ketone or aldehyde?
In a conjugated ketone or aldehyde, nucleophiles could attack the double bond or the carbonyl carbon. I have two examples that differ in the location of initial attack, and I am wondering what ...
- 105
1
vote
0
answers
52
views
How do I make this terminal alkyne into a methyl alkene on the third carbon?
How do I get from but-3-yn-1-ylbenzene to (3-methylbut-3-en-1-yl)benzene? I have tried $\ce{NaNH2}$ in $\ce{CH3Br}$ and then $\ce{H2}$ with a Lindlar catalyst, but that adds the methyl group at the ...
- 59
-1
votes
1
answer
81
views
How can I protect the ester group from reduction? [closed]
If I process this reaction the NaBH4 will also reduced the ester group to alcohol. I want to convert the Nitro (-NO2) functional group to Amine (-NH2) without disturbing the Ester group. So, my ...
- 11
3
votes
1
answer
122
views
Conditions for Pd/C reduction of alkene
I am trying to do a $\ce{H2}$ reduction of cyclic alkene (otherwise simple hydrocarbon with 1 methyl group along with the chain about the weakly-strained cycle) using $\ce{Pd/C}$, the cycloalkene ...
- 39
2
votes
1
answer
1k
views
Why does DIBAL-H not reduce esters to alcohols directly?
This source says that DIBAL-H reduces esters to aldehydes. Further, it says that, like NaBH4, it reduces aldehydes too.
Why in reduction of ester, the aldehyde so formed is not converted to alcohol, ...
- 23
0
votes
0
answers
312
views
What is the effect of NaNO2/HCl at 0-5° C on Nitro group?
In this particular reaction firstly $\ce{NaNO2/HCl}$ at $\pu{0-5°C}$ was taken and after that $\ce{H2/Ni}$ .
But what I doubt is, was there any role of $\ce{NaNO2/HCl}$ at $\pu{0-5°C}$ ?
Since only ...
- 41
-2
votes
1
answer
786
views
Does sodium borohydride reduces alkyne? [closed]
Will an isolated Alkyne or an alkene be reduced using sodium borohydride ($\ce{NaBH4}$)?
- 41
2
votes
0
answers
100
views
Red P+HI with some specific functional groups
I've seen the related question (Does RedP+HI reduce all carbon functional groups to alkane?). Although the question is admittedly similar, neither the answer provided nor the document linked in it ...
- 43
1
vote
0
answers
87
views
Rearrangement vs. Ring Strain in Cyclobutanecarboxaldehyde Nucleophilic Reaction
Predict the major product of the following reaction:
Note: Product A is incorrectly marked as secondary halide, it should have been primary halide
This question appeared in an national level ...
- 78
0
votes
0
answers
322
views
Why isn't the Leuckart reaction used to make (meth)amphetamine?
For example, in Breaking Bad, they synthesize meth from phenylacetone.
Why not just use methylammonium formate, if they already have methylamine?
- 111
1
vote
1
answer
275
views
Reduction of unsymmetrical ketones using BINAL-H (Enantioselectivity)
I am struggling with a problem regarding the enantioselectivity of BINAL-H for quite some time now.
The reaction scheme shows the reaction with (S)-BINAL-H as it is observed plus the transition state ...
- 21
4
votes
2
answers
536
views
Partial reduction of anthraquinone to anthrone using stannous chloride?
I've heard of using $\ce{SnCl2}$ in the Stephen's reaction where you reduce a nitrile down to an aldehyde. I've come across a laboratory manual that discusses using tin in the partial reduction of ...
- 41
3
votes
1
answer
899
views
Acid hydrolysis of Birch-reduced Anisole
The following is a question from Advanced problems in organic chemistry by MS Chouhan:
Product $A$ is rather straightforward:
and on acidic hydrolysis, the following reaction takes place:
Here the ...
- 101
0
votes
1
answer
1k
views
Why adding sodium bicarbonate quenches a reductive amination using sodium triacetoxyborohydride?
I'm planning to do a reductive amination reaction between methyl pyruvate and benzylamine using sodium triacetoxyborohydride, $\ce{NaBH(OAc)3}.$ Acetic acid is used as a catalyst for protonating the ...
1
vote
0
answers
58
views
Chlorinated hydrocarbon destruction
What's a convenient method for lab-scale destruction of chlorinated hydrocarbons?
Reductive dechlorination, total oxidation are fine as well as other routes you want to point out. If specific ...
- 141
3
votes
1
answer
339
views
Why does BH3/THF reduce the carbonyl group to a methylene rather than an alcohol?
This reaction is taken from: Pintér, Á.; Sud, A.; Sureshkumar, D.; Klussmann, M. Autoxidative Carbon-Carbon Bond Formation from Carbon-Hydrogen Bonds. Angew. Chem., Int. Ed. 2010, 49 (29), 5004–5007. ...
- 31
3
votes
1
answer
425
views
Does red phosphorus with hydriodic acid reduce all alkyl halides?
$\ce{HI/P}$ is used for reduction of alcohols, aldehydes, ketones and acids to alkanes. As for alkyl halides, I have read that only alkyl iodides are reduced, whereas other alkyl halides do not:
$$\ce{...
- 129
2
votes
0
answers
86
views
Reduction of orthoesters and acetals with LiAlH4
As I know, orthoesters react with $\ce{LiAlH4}$. After searching on the Internet I’ve found that acetals react with $\ce{LiAlH4}$ in the presence of $\ce{AlCl3}$. Why can’t acetals be reduced only in ...
- 89
2
votes
0
answers
49
views
Naftiridine hydrogenation
I was reading an article about the synthesis of 1,2,3,4 tetrahydronaphtyridine and I found this image.
I don't understand why the major product of hydrogenation is the less substituted and not the ...
- 21
0
votes
0
answers
147
views
How does deprotonation works?
I've been studying organic chemistry and came across this example :
CH3-CH2-CH(+)-CH3 ---> CH3-CH=CH-CH3, the explanation the textbook gave was related to deprotonation. I've tried drawing lewis ...
- 51
-1
votes
2
answers
216
views
Reaction mechanism of phenylhydrazine with carbonyl
I am currently working on the following problem, but I don’t know how it is solved:
I guess it is a Fischer-Indol synthesis, but I am not sure. This is what I got:
Any help would really be ...
- 23
-1
votes
1
answer
42
views
Where does Aluminum Hydroxide come from in a reduction of a ketone by LAH? [closed]
The experiment was done in a Laboratory. A ketone was reduced with LAH in THF under reflux.
At the end of the reaction, the protocol stated to add water until there is no more H2 released. The H2 ...
- 67
1
vote
0
answers
277
views
Selective reduction of aromatic nitro group
In the following compound, is it possible to selectively reduce the aromatic nitro group to an amine, as shown in the reaction?
I fear that the methods usually used to reduce aromatic nitro compounds,...
- 773
0
votes
1
answer
486
views
Are terminals alkyne reduced by Na/liq NH3? [closed]
By the mechanism, it appears that any alkyne should be reduced, but I couldn't find any source supporting or disapproving it. One possibility is that first acid-base rxn takes place but still the ...
- 308
0
votes
1
answer
128
views
Hydrogenation of pent-4-en-2-one
If one equivalent of $\ce{H2}/\ce{Pt}$ is made to react with one equivalent of pent-4-en-2-one, what will be the product formed?
- 126
1
vote
1
answer
1k
views
Method to remove impurities from acetaminophen synthesis experiment
I'd like to know about impurities from acetaminophen synthesis experiment. Are there any impurities produced by oxidation of p-aminophenol? If there is any impurity produced by oxidation of p-...
- 41
3
votes
0
answers
83
views
How is this Clemmensen Reduction taking place? [closed]
How did that isotopically labelled Carbon migrate? I know that an carbanion is formed, but I am not able to conclude the final product. Please Help
0
votes
1
answer
3k
views
Dextrose equivalent values (DE) of the most common sugars
What are the dextrose equivalent values (DE) of lactose, and other common sugars?
Some data like the values for sucrose (0), maltodextrin (x<20), maltose (52), and glucose (100) can be found at ...
- 175
5
votes
1
answer
312
views
Sodium metal and alcohol reduction of imines. Is it possible?
It is known that sodium metal in ethanol with toluene under reflux can reduce nitriles to amines1 and can also reduce oximes and schiff bases to primary amines and secondary amines respectively2. Is ...
- 51
5
votes
2
answers
718
views
Can Mg/ether reduce carbonyl groups?
One of the ways of preparing Grignard reagent is:
$\ce{R-X ->[Mg/ether] R-MgX}$
However let's assume that a carbonyl group is present along with a halide in the substrate. Will $\ce{Mg/ether}$ ...
- 1,409
3
votes
1
answer
1k
views
Reduction of conjugated ketone with lithium aluminium hydride
I came across a question about reduction of a conjugated ketone with $\ce{LiAlH4}$.
Although it seemed quite easy at first sight, everything became cloudy as I dug deeper. My doubts regarding the ...
- 292
1
vote
1
answer
907
views
Can a Lindlar catalyst reduce aldehydes, nitriles, and carbonitriles?
The major product obtained in the following reaction is:
Question source: JEE Main 2019
The molecule shown as product is the official answer given by JEE from the given options.
I have written the ...
- 804
9
votes
1
answer
539
views
Why does LiAlH4 reduce the double bond of cinnamaldehyde, whereas it does not reduce the double bond in crotonaldehyde?
$\ce{LiAlH4}$ is a strong reducing agent capable of breaking the double bonds. It does break the double bonds in cinnamaldehyde.
Shouldn't $\ce{LiAlH4}$ be able to break the double bond in ...
- 93
3
votes
0
answers
56
views
Why do different products form when alkali halide reacts with zinc in polar protic and aprotic solvents?
Let's take an alkali halide such as $\ce{CH3CH2Cl}$ the two reactions in polar protic and aprotic solvents are as follows:
$$
\begin{align}
\ce{CH3CH2Cl &->[Zn, CH3OH] CH3CH3}\tag{R1} \\
\ce{...
- 1,409
3
votes
0
answers
55
views
Does lithium aluminium hydride react with conjugated dienes? [closed]
I have searched many websites, but was unable to find if $\ce{LiAlH4}$ is able to reduce conjugated dienes, such as styrene to ethylbenzene or 1,3-butadiene to 1-butene.
7
votes
2
answers
428
views
What is the major product in the reaction between 4-chloropentanal and lithium aluminium hydride?
What would be the major product between 4-chloropentanal and $\ce{LiAlH4}$?
After the reduction of the aldehyde, would the hydroxyl group formed at $\ce{C-1}$ attack $\ce{C-4}$ causing cyclization to ...
- 145
3
votes
0
answers
53
views
Conjugated diene + Na in liq.NH3 [duplicate]
I learned that alkynes gets reduced on addition of $\ce{Na}$ in liquid $\ce{NH3}$ to form alkenes (which is not further reduced). Recently I came across a reaction where a conjugated diene was treated ...
5
votes
0
answers
209
views
Reactivity order of DIBAL-H and diborane with esters and acids
I have been taught in class that
DIBAL-H is more reactive towards esters than carboxylic acids while opposite is true for diborane.
Also DIBAL-H mentioned is taken under low temperatures (−78 °C).
I ...
- 434
1
vote
0
answers
45
views
Why negative charge delocalises away from electronegative atoms
In the mechanism for the Wolff-Kishner reduction, after the $\ce{OH-}$ abstracts a proton, the resulting negative charge delocalises away from the nitrogen atom to the carbon, and the subsequent ...
- 1,136
7
votes
1
answer
962
views
On the use of hexane in the organic reduction by DIBAL-H
In some variations of the organic reduction by DIBAL-H, I've seen hexane used, as in this equation from this website;
I've looked it up, but I haven't seen any explanation for why hexane's used there....
- 1,136
7
votes
2
answers
348
views
What reagents are used to selectively reduce 2,2,3‐trimethyloxirane to secondary and tertiary alcohols?
Problem
Answer
Questions
I know $\ce {LiAlH4}$ is a reducing agent because it gives four $\ce{H-}$ and will attack on our reactant on carbon with less substituents, i.e. in this case on $\ce{-CH-}$ ...
- 445
-2
votes
1
answer
297
views
Birch reduction in diethyl ether [closed]
I wanna ask, why I can't find any experiment using amonia dissolved in diethyl ether. You could bypass need of cooling the amonia under it boiling point by gassing the amonia to diethyl ether. Why it ...
6
votes
1
answer
327
views
How is the hydrazone formed in the Wolff-Kishner reduction?
In the Wolff-Kishner reduction the first step is to react a carbonyl with hydrazine to form a hydrazone. The later steps of the reaction requires a strong base to cause loss of nitrogen.
However, the ...
- 814
1
vote
1
answer
3k
views
Why can't sodium borohydride reduce carboxylic acid and ester groups? [duplicate]
Sodium borohydride ($\ce{NaBH_4}$) is a reducing agent used in various organic reaction to reduce aldehydes, ketones and acyl chlorides.
Why can't sodium borohydride reduce carboxylic acid groups and ...
- 547
5
votes
1
answer
554
views
Can sodium borohydride reduce hemiacetals?
In the synthesis of Panacene by Canesi et al. [1], a step involves the installation of an $\ce{-OH}$ group on a double bond, using the oxymercuration-demercuration procedure. However, the product ...
- 489