50
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Do molecules with bridges through rings exist?
I'm not sure about the existence of molecules with bridges through rings. However, there are several publications of synthesis of molecules mimicking wheels and axles ([2]rotaxanes; The “[2]” refers ...
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30
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Do molecules with bridges through rings exist?
A variation on this theme is Ice VII, in which two cubic ice structures are intertwined with hydrogen bonds from each component structure passing through the hydrogen-bonded rings formed by the other ...
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23
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Has anyone sysnthesized perfluorocubane (AKA octafluorocubane)?
[Caveat: This is not so much a question-and-answer as a desire to share Derek Lowe's article in his inimitable style. Given enough down-votes, I'll delete both Q-&-A. But enjoy the synthesis ...
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20
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What is the mechanism of the reaction between hexane-2,5-dione and nitrous acid?
As you may know from diazotisation reactions, $\ce{HNO2}$ is a generator of the nitrosonium cation, $\ce{NO+}$. Electrophiles like these can react with the enol tautomer of hexanedione:
Following ...
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19
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What does washing and drying a solution mean?
This is standard for purifying substances.
To wash means to add your product solution to an aqueous solution (or just water, but frequently a saturated solution) to a separatory funnel. After shaking, ...
- 17.3k
18
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Reactions of alcohol with sulfuric acid
This article on Wikipedia says your compound, ethyl sulphate, can be synthesized, by adding sulfuric acid drop-wise to boiling ethanol and temperature should be kept below 413K which agrees with your ...
- 4,578
18
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Mechanism for basic hydrolysis of α-chloronitrile to ketone?
Your analysis is slightly incorrect, actually. If you do a $\mathrm{S_N2}$ on the chloride, hydrolyse the nitrile, and decarboxylate, you end up with the wrong oxidation state:
Instead, if you ...
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18
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Understanding the synthesis of twistane
The first step is a conversion of the nitrile into a carboxylic acid, in the literature Martin Olbrich, Peter Mayer, and Dirk Trauner (J. Org. Chem., 2015, 80, 2042-2055) used KOH in ethylene glycol ...
- 5,151
18
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ICHO Synthesis Problem 2018
You have asked quite a number of questions in your post so let's tackle it one by one.
Why does the oxidation take place at that particular nitrogen atom?
To understand this, we first need to ...
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16
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Are there any significant uses of the compound formed by magnesium and anthracene?
It seems like an idea of using magnesium anthracene systems for the $\ce{MgH2}$ production persisted since 1980s [1] till late 2000s, when new more efficient method with better scalability for ...
- 37.4k
16
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Why doesn't aromatic substitution add at multiple positions in one reaction?
The rate of Aromatic substitution depends upon the activity of the aromatic system, because when the collision happens the aromatic system has to donate electrons to an electrophile.
In the example ...
- 3,075
15
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Which platonic solids have been built as carbon skeletons?
The previous answer and comments have already listed out the known platonic hydrocarbons, however, since the OP had expressed an interest in the synthesis of these platonic hydrocarbons in one of his ...
- 8,465
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What is the mechanism of the reaction between hexane-2,5-dione and nitrous acid?
Orthocresol did a great job describing how to get to the isoxazole methyl ketone. However, nitrous acid can be an oxidant. The methyl ketone in the presence of mineral acid, which you need to get the ...
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15
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Why doesn't aromatic substitution add at multiple positions in one reaction?
During a electrophilic aromatic substitution, it is always possible to have multiple substitutions during one reaction. However, your example is not the ideal one for a discussion. As noted, Oscar ...
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14
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What is the mechanism of azulene synthesis?
The @orthocresol link to the Zincke reaction is a good start to the mechanism. You are correct about the first step. Dimethylamine adds to the electrophilic pyridinium salt 1 as illustrated in 1 $\...
- 16.4k
14
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What is the best way to deprotonate a methyl group?
The deprotonation of 1a has been conducted with LDA/THF and subsequently converted to the phosphonate.[1] Alternatively, bromide 3a has been prepared[2] and converted[3] to phosphonate 2a via an ...
- 16.4k
13
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How can one synthesise a conjugated alkyne chain?
A carbenoid Fritsch-Buttenberg-Wiechell (FBW) rearrangement of a substituted dibromoolefinic precursor is used to generate a lithium acetylide, and subsequent trapping with carbon-based electrophiles ...
- 21.5k
13
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Does germanium(IV) chloride have to be handled under inert atmosphere?
At times like this, you always refer to the material safety data sheet (MSDS). Have a look:
Upon contact with water or moist air this material reacts to release corrosive and toxic hydrogen chloride ...
- 25k
12
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Fluorescein synthesis
This reaction is considered a modified Friedel-crafts acylation. The reaction is formally a series of electrophilic aromatic substitutions, with hydroxyl leaving groups picking up protons (1), however ...
- 2,324
12
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Synthesize acyl chloride from aldehyde
There are many ways to affect the transformation, as you have realised, and many of which Loong has detailed below in his post.
This answer gives one method which I would be confident of working ...
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12
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Why is the Friedel-Crafts alkylation of nitrobenzene disfavoured?
The nitro group is so deactivating that yields are really poor for Friedel-Crafts reactions with nitrobenzene; not even the meta-substituted product is found in good yield. In fact, nitrobenzene is ...
- 742
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Synthesising Complex Aromatic Compound
An alternative approach might be something like this. The tertiary alcohol product with two identical groups suggests that a Grignard reaction with an ester might be a useful step.
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12
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Kolbe Schmitt followed by methylation
Collecting my comment thoughts together, there is an early demethylation step in this synthesis. Structure 1 is the result of carboxylation while methylation provides ester N. Friedel-Crafts ...
- 16.4k
12
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How are organic compounds with radioactive atoms synthesized?
The current methods employed for synthesis fall into the following three categories1:
Chemical synthesis
Biochemical methods
Isotope exchange reactions
Chemical Synthesis:
Most chemical syntheses ...
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11
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How to develop a retrosynthesis plan for 2-[(E)-2-(3-bromophenyl)ethenyl]-1,3-benzoxazole?
Extempore, this should be available by the reaction of 3-bromocinnamaldehyde with 2-aminophenol. Samarium triflate as a catalyst might be a good idea.
In any case, I'd start the retrosynthesis at the ...
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11
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N-fluorosuccinimide: any scope?
Maybe NFS doesn't work well? Bear in mind that bonds from a second-period element to fluorine are generally stronger and less labile than the corresponding bonds to heavier halogens. If that's true, ...
- 53.1k
11
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Anthracine blue composition
Springmühl indeed reported Anthracene Blue (orig. "Anthracenblau" (German)) from an intermediate with brutto-formula $\ce{C14H7O3}$. It seems like this method only worked well at a lab scale....
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11
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Why is tert-butoxide often used in elimination reactions when it is not necessary?
Several reasons:
t-BuOK is especially known as a strong base, and a poor nucleophile. Its large, bulky structure causes it to perform exceptionally poorly in substitution, literally eliminating any ...
- 2,885
11
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Why benzenediazonium bromide and iodide are of little interest?
There is indeed very little to be found in the literature.
A recent Russian paper (Ref.1) mentions benzenediazonium bromide as a reactant. This thesis from 1975 (Ref.2) contains a preparation of ...
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