Unanswered Questions
617 questions with no upvoted or accepted answers
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Do Cyclohexane-1,3-diones Give Positive Haloform Reactions?
Recently a post appeared on ChemSE asking why cyclohexane-1,3-dione (dihydroresorcinol) 1a doesn’t give a positive iodoform test. Unfortunately, the post was subsequently taken down after several ...
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13
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1
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Why do alpha-hydroxy ketones respond positively to Tollens', Fehling's, Benedict's, Schiff's and HgCl2 tests?
I learnt from a certain textbook that aldehydes and formic acid respond positively to Tollens', Fehling's, Benedict's, Schiff's and HgCl2 tests.
However, in another textbook I read that even alpha-...
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Why does the reaction of sodium nitrate, aluminium, and sodium hydroxide yield ammonia?
From Russian test problem 4301:
$$\ce{3NaNO3 + 8Al + 5NaOH + 18H2O -> 8Na[Al(OH)4] + 3NH3(g)}$$
How does ammonia evolve here? Is it that we get hydrogen gas evolving in the reaction between Al and ...
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8
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Alcohol to Ketone by CrO3 in cyclohexane
I have encountered an exercise question on conformation of cyclohexane and there is a statement saying, 'converting alcohol to ketone by CrO3 is much faster when R-OH is in axial position'. I would ...
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8
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Do all α-hydroxy ketones give Tollens’ test?
It is well known that terminal α-hydroxy ketones give Tollens’ test, via tautomerisation. Also, α-hydroxy ketones flanked by aromatic groups give Tollens’ test, such as benzoin.
But do all α-hydroxy ...
CommunityBot
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8
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Grubbs, Wittig & hydroboration reactions and Woodward-Hoffmann rules
Several organic mechanisms I know involve [2+2] cycloadditions and retro-[2+2] cycloadditions, namely:
The Wittig reaction
Hydroboration of an alkene
Olefin metathesis (using Grubbs' catalyst)
How ...
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7
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Textbook suggests secondary alkyl halides do not undergo SN1 reaction
The 8th edition of Organic Chemistry by Paula Bruice suggests that secondary alkyl halides do not undergo SN2 reactions. However, many other sources state the opposite. So, what is the correct answer?
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7
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Solve this chemical or biological mystery
I hope this is the best place to pose this unique question. Please forgive me if it's not.
I went into a closet to get a prescription medication that was filled about a year ago.
The label on the ...
7
votes
1
answer
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Orientation in benzene rings with more than one substituent
Why is it that the chlorination of 1-chloro-3-nitrobenzene (18) gives 1,4-dichloro-2-nitrobenzene (19) as the major product, 1,2-dichloro-3-nitrobenzene (20) as a minor product and 1,2-dichloro-4-...
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How to determine the surface reaction rate and equilibrium constant for a reaction between a solid site species and gas species
Consider the following reaction mechanism 1:
S1: $\ce{C-H (s) + H (g) <=> C^\star (s) + H2 (g)}$
S2: $\ce{C^\star (s) + H (g) => C-H (s)}$
S3: $\ce{C^\star (s) + C2H2 (g) => C-H (s) + H(g) ...
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6
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3-Step Transformation to Humulone
I have some ideas on how this transformation may occur. We're currently studying Ch. 3 (Polar Rxn's under Acidic Conditions) from Grossman's book.
I've found some data online that shows we can perform ...
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6
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Difference between Tishchenko reaction and Meerwein-Ponndorf-Verley reduction
For the Tishchenko reaction, Al(OEt)3 is used as reagent where an aldehyde is oxidized as well as reduced, so it's a redox reaction.
Whereas in Meerwein-Ponndorf-Verley reduction, an aldehyde is ...
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6
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Mechanism for Ce(IV) Oxidation of Naphthalene
S. Cotton's Lanthanide and Actinide Chemistry reports that naphthalene can be oxidized to naphthalene-1,4-dione using cerric ammonium sulfate (CAS), $\ce{MeCN, H2SO4},$ and $\ce{H2O}$.1 No mechanism ...
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Diazo Coupling reaction with para-substituted phenol?
Usually Diazo coupling occurs at para-position unless the para-position is occupied, in which case coupling occurs at ortho-position.
While solving questions I found in both the cases as shown, the ...
6
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Which is the correct mechanism for the ozonolysis of an alkyne?
According to Organic Chemistry by Jonathan Clayden, Nick Greeves and Stuart Warren (2nd edition), the mechanism for alkene ozonolysis is given as
In Advanced Organic Chemistry, Part B: Reactions and ...
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