Questions tagged [reagents]
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33 questions
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I have a question about the selective chlorination mechanism of galactopyranosyl-(1 -> 6)-O-a-D-glucopyranosyl-(1 -> 2)-D-fructofuranoside
Could you please provide a full mechanism of selective chlorination of galactopyranosyl-(1 -> 6)-O-a-D-glucopyranosyl-(1 -> 2)-D-fructofuranoside using the TPP/thionyl chloride as a chlorinating ...
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Oxidation of 1,2 dicarbonyls by tollens reagent
According to the wiki page on Tollen's reagent
https://en.wikipedia.org/wiki/Tollens%27_reagent#Qualitative_organic_analysis
It also gives a positive test with hydrazines, hydrazones, α-hydroxy ...
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Difference in reactivity of sodium ethoxide and NaOH in ethanol
What is the difference in the reaction that proceeds when we use the reagent $\ce{C2H5O- Na+}$ and $\ce{NaOH}$ in $\ce{C2H5OH}$ in with, say ethyl chloride. Is the latter considered to be "...
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Regarding Hinsberg reagent, potassium salt of primary amine soluble in base become insoluble after acidification?
Distinguish between ethylamine, diethylamine and triethylamine by using Hinsberg's reagent?
Ans. This reaction is useful for the distinction of primary, secondary and tertiary amines.
(i) Primary ...
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Find the missing chemical structures in the reaction sequence
I came across the following question, where a set of reagents are used, starting from a carbohydrate derivative.
I understand that this is some total synthesis reaction, but I cannot find which one.
...
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Recovery of antimony trichloride
I have bought 250 g of old antimony trichloride bottle (very cheap), it was never opened because it is sealed from manufacturer. But it was probably not stored well, or seal is not good, because there ...
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Can Acyl halides react with PCl5, if not, why?
I was searching for reaction of $\ce{PCl5}$ with carboxylic acids and found this mechanism:
Here a corresponding acyl chloride is formed from a carboxylic acid.
Now I doubt if this is the final ...
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Advice on Evaporation / Leakage of Marquis and Ehrlich's reagents
I had ordered both Marquis and Ehrlich's reagents from a manufacturer and they came in eye dropper like bottles inside of prescription pill like bottles. The perscription pill bottles also had cotton ...
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Blue Tinge for White Paint [closed]
I am trying to make an aqueous white paint with Mica and TiO2 as mainstay that gives a slight tinge of blue when it dries but should remain white while in solution.
So far I have tried optical ...
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Action of EtONa/EtOH on compound containing -CN group
In the above question, I know compound A will be prepared by just replacing -Cl with -CN group in the starting compound. I wanted to know what work would be C$_2$H$_5$ONa/EtOH doing in order to make ...
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Why do we have to use anhydrous AlCl3 in Gatterman-Koch Reaction?
In reference to a Gattermann-Koch reaction, such as the one shown below:
Why does $\ce{AlCl_3}$ have to be anhydrous?
Why can't we just use normal $\ce{AlCl_3(H2O)_6}$?
What would the reaction look ...
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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 ...
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How can I store reagent under inert gas?
I need to store some aliquots of 2,3,5-tribromothiophene. I searched for how to store reagent under inert gas, And I found this : https://avantilipids.com/tech-support/faqs/protect-from-oxidation
In ...
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What is the difference between lead tetraacetate and sodium periodate as reagents?
I recently came across this question which has confused me about the usage of $\ce{Pb(OAc)4}$ and $\ce{NaIO4}$ reagent.
Both the reagents have nearly the same cyclization mechanism, but the answer to ...
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Major product in reaction of butan-2-one + selenium dioxide
When reading about $\ce{SeO_2}$ I read this following reaction:
$\ce{CH3CH2COCH3 ->[SeO2] CH3CH2COCHO + CH3COCOCH3}$
In the following reaction it was stated that $\ce{CH3CH2COCHO}$ was the major ...
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Reagent notation: meaning of dash(-) and line(|) or slash(\) in reagents
I've seen a lot of reagents which have a slash between two compounds, such as Lindlar's catalyst which is $\ce{H2}$ along with $\ce{Pd|BaSO4}$. I know that the sulphur is a poison here but in general, ...
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Dihaloalkane reaction with sodamide/ammonia [closed]
In the following sequence of reactions:
$$\ce{CH3-CH2-CH2-I ->[\text{Alc.}~KOH] \textbf{A} ->[Br2] \textbf{B} ->[NaNH2/NH3] \textbf{C}}$$
the product C is:
alkene
alkanol
alkyne
alkylamine
...
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How can one determine if all reagents will react in the reaction? [closed]
Is it correct that all the reagents above the arrow will participate to form an intermediate product, to which the reagents below the arrow are then added, and they react to form the final product?
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Why isn't sodium hydrogen phthalate used instead of KHP?
Why is potassium hydrogen phthalate (KHP) ubiquitously synthesized and used as a primary standard, while sodium hydrogen phthalate isn't even available to buy?
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TKN: Why are they called Missouri tablets?
When analyzing for Total Kjeldahl Nitrogen (TKN), you can make a copper sulfate digestion solution in the lab or purchase a variety of pre-prepared digesting tablets for example on VWR. My question is,...
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Reaction of 1,2-diketones with periodic acid [closed]
$\ce{HIO4}$ can oxidise alcohols. But does $\ce{HIO4}$ undergo any reaction/act as oxidant with 1,2-diketones?
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extract cellulose from CMC using cuoxam reagent (schweizer's reagent)
Good day, I am new in the field of chemestry. My question is, if it is possible to reverse or extract (I am not very sure how to say it), cellulose from carboxymethyl cellulose (CMC) by the use of ...
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Why don't we use silver hydroxide instead of Tollen's reagent for test of aldehydes? [closed]
AgNO3+NH4OH=AgOH+NH4NO3
AgOH is used for the reaction with aldehyde. But why can't we use silver hydroxide directly?
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Labware to handle hot aqueous NaOH
This question regarding appropriate handling of hot concentrated aqueous $\ce{NaOH}$ - with particular concern for avoiding dissolution of borosilicate glassware and contamination of the $\ce{NaOH}$ ...
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Can I make a mirror on PET plastic using Tollen's reaction?
I want to make a very shiny surface, like a mirror. I tried to use chrome paint but it's barely shiny. It's more like gray even though I bought one of the most expensive chrome looking paint.
I know ...
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1000 mg/L alkalinity as CaCO3 standard preparation [closed]
How do I prepare a 1000 mg/L alkalinity as CaCO3 standard? I found a method that says to dissolve 1.06 g of sodium carbonate (Na2CO3) in 1L of water but I'm not sure why I can't use 1g instead? ...
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How tartaric acid gives Tollen's test?
I wanted to know how Tollen's test is given by tartaric acid. Google searches say that it belongs to some "Hydroxyl" group. I know that it oxidises aliphatic and aromatic aldehydes along with α-...
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Should I use MCPBA here?
I came across a question that asked for a method to convert propene to glycerol. I used the method in the pic, but I'm worried about two steps-
Step-2, This reaction is just made up by myself! I'm ...
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Detecting alkaloids - Dragendorff's reagent
I am writing a book and as part of the plot one of the characters has a plant that contains alkaloids in tincture form. They want to do a test to detect for the alkaloids so they use the Dragendorff's ...
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Wetting agent for H2O2 solution
I need to increase the wetting of an $\ce{H2O2}$ solution on ceramic surfaces. Does anyone know of a common chemical I can use for this?
The properties it would ideally have are:
Increases wetting ...
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Salt used in Perkin Reaction
The Perkin reaction gives an α,β-unsaturated aromatic acid by the aldol condensation of an aromatic aldehyde and an acid anhydride, in the presence of an alkali salt of the acid. Here is an a diagram ...
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Why does 3-hydroxy-butan-2-one give positive Tollens' test?
Why does 3-hydroxy-butan-2-one give a positive Tollens' test despite the absence of an aldehyde group? What is the mechanism?
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Is hydronium an electrophile, nucleophile, both or neither?
Is hydronium an electrophile or a nucleophile? I expected $\ce{H3O+}$ to be a nucleophile due to the presence of electrons in the $\ce{2p}$ orbitals of $\ce{O}$. But the answer key of the test states ...
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