Questions tagged [synthesis]
Synthesis is a purposeful execution of chemical reactions to obtain the desired product. Applies to long and complex natural product syntheses as much as to short one or two-step syntheses. This also covers synthetic problem sets and retrosynthetic analyses.
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Synthesis of racemic nicotine
In my advanced organic chemistry course, we were asked to fill the following scheme for the synthesis of racemic nicotine, starting with ethyl nicotinate:
Exercise 6: Complete the following scheme ...
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How to avoid side reactions when making boronic esters (Homocoupling, Hydrogen specie)?
I have been working with suzuki couplings using substituted naphtalenes (typically 2-bromo-7-R-naphtalene) for a while now, and making the boronic specie is always a pain.
I can't make the boronic ...
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Will a nitro aryl resist an halogen exchange using nBuLi?
I would like to boronate 2-bromo-6-nitro-naphtalene using nBuLi and quenching with 2-Isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane. Since there is no alpha proton to the nitro, and that the nitro ...
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After adding the electrophile (BOMe3) in an halogen exchange (nBuLi) reaction, why do we leave the reaction stir overnight?
Very basic question.
In all the procedures for halogen exchange reactions reported using boronic compounds, the reaction is left to run ON at room temperature after addition of the boronic specie.
In ...
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(Di)chlorination of phosphonic acid ester
What is the best way to do this reaction to form the dichloride as an reactive intermediate when the substituent R is acid sensitive?
In the literature the reaction is either performed with PCl5, a ...
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Compatibility of DCM/CCl3 with sodium hydride
In our undergraduate studies we were told that chlorinated solvents should not get in contact with alkaline elements like sodium, potassium etc., due to the violent reaction that will form the ...
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Are there methods of synthesizing rubber from plant materials?
First and foremost, I am not talking about natural rubber. I am asking if there are any industrially used methods of synthesizing rubber from agricultural products as opposed to synthesis of rubber ...
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Synthesis of (S)-2-hydroxy-4-oxohex-5-enal
I am currently working on a total synthesis strategy, but I was told that a key step in my total synthesis probably wouldn't work, so now I am trying to figure out a way around it. The compound that I ...
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Quenching reagents for specific reaction
A reaction general procedure is given as follows:
A mixture of 2-fluoro-5-iodo pyridine $(\pu{1.0 mmol})$, methyl
acetoacetate $(\pu{3.0 mmol})$, $\ce{CuI}$ $(\pu{10 mol\%})$, $\ce{K3PO4}$ $(\pu{3.0 ...
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Synthesis of 1-phenyl-2-buten-1-one using an aldol condensation
I asked my students to suggest a route of synthesis for 1-phenyl-2-buten-1-one [1], using a Claisen or aldol condensation. One student had the idea of forming the aromatic ring as part of the reaction,...
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What is the purpose of chloromercuration of HgOAc group?
In some reactions using $\ce{Hg(OAc)_2}$, I saw some cases that convert $\ce{-HgOAc}$ group into $\ce{-HgCl}$ group by adding $\ce{NaCl}$. Below is one example, the synthesis of (+)-preussin.
Mercury(...
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Synthesis of polypropylene
So, I have two questions regarding the synthesis of polypropylene:
I have tried looking everywhere but couldn't find a detailed mechanism for the termination step of the synthesis of polypropylene (...
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Synthesizing Cyclotetrazane from Hydrazine and Diazene?
Could cyclotetrazane — a compound with nitrogen atoms arranged in a square configuration — be synthesized? A hydrogen atom would be bonded to each vertex (nitrogen atom):
Could cyclotetrazane be made ...
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Palladium coupling reactions and purification
I tried to synthesize 2-(6-fluoropyridin-3-yl) acetic acid from 5-(Chloromethyl)-2-fluoropyridine using Pd(OAc)2/PPh3 catalyst,Na2CO3 and DCC. I eluted my product on TLC with Ethyl acetate/hexane/...
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Electrophilic fluorination power: selectfluor vs NFSI
I want to fluorinate the methylene hydrogens between an aryl group and a phosponate ester. The reaction is similar (not identical) to this one:
For some reason on the literature people are using very ...