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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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 ...
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Could a de-commissioned synthetic ammonia plant be adapted for use in removing CO2 from the atmosphere (DAC)?
I was prompted to ask this question by viewing a disused $\ce{NH3}$ plant in the harbour near where I live.
Like many it functioned using a methane feedstock from a natural gas find off the coast. I ...
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With two reagents common on Mars, fluorite and CO2, how would I produce carbon tetrafluoride?
The hypothetical terraforming of Mars would require the heating of the atmosphere. A commonly suggested method is the in-situ production of fluorocarbons, powerful greenhouse gases.
For example, ...
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Synthesize pivaloyloxymethyl ester, but with a substrate that is a terrible nucleophile
I want to synthesize an pivaloyloxymethyl ester from a fluorophosphonic acid. The idea is, to make a compound cell permeable that than be cleaved in the cell by enzymes. Apparently, the acid is a very ...
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Why cool a reaction down when adding reagents if you're only going to reflux subsequently?
I've seen several procedures using thionyl chloride (SOCl2) to make an ester, where the first step is to add the thionyl chloride to the reagent/solvent on ice or subzero temperature, followed ...
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Why does hydrogen peroxide decompose during the oxidation of an aryl amine to and nitroarene (rt) and what are the possible overoxidation products?
Small scale:
I attempted the oxidation of an aryl amine (2-amino-6-bromonaphtalene) to the nitroarene using hydrogen peroxide (ArNH2, H2O2, MeCN (15 mL as solvent). After trying it on small scale (0.1 ...
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What is the difference in reactivity between the various borates (trimethyl, triethyl, triisopropyl borate) to form boronic acids?
For the transformation of 1,3-dibromobenzene to bromobenzene boronic acid, different groups use different boration reagents namely trimethylborate, triethyborate and triisopropylborate).
The reaction ...
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Need Suggestion for Picking the Right Solvent for Column Chromatography
I've completed my reactions, and based on the stoichiometry and TLC analysis, I think my mixture should contain 3-4 compounds:
Ethyl gallate (my product)
Gallic acid (the reagent/starting material)
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Exchange of Fluorine to Oxygen for Fluorophosphonic acid by silylating agents or other methods?
[Warning, long post!]
Dear all,
I am confronted with a seemingly easy transformation. I want to remove a fluorine atom at a fluor phosphonic acid salt. The usual method to achieve this is the basic ...
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How does the following cyclization reaction work?
The following is a reaction from a school provided lab manual. However, I am unable to find anything similar to the cyclization reaction taking place. All of the reactions I have found online make use ...
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TMSBr and 2,4,6 Collidin in Acetonitrile leads to white precipitate
I want to hydrolyse a phosphonic acid ester with TMSBr.
I think this reaction works only with the addition of base. Without base, the product in my specific case is prone to deterioation due to acid ...
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What is this gel byproduct of acetylsalicylic acid recrystallization?
I did a very simple acetylsalicylic acid synthesis from salicylic acid and acetic anhydride (with phosphoric acid as a catalyst). After rinsing, filtering and drying the product I dissolved it in ...
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Removing DCC and its by-product from Steglich Esterfication
In my small research, I want to synthesize 3 alkyl gallates (ethyl gallate, butyl gallate, and hexyl gallate), and here's my overall reaction using Steglich esterification):
However, from reading ...
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Question about the differences of white and grey NaH properties
We are having some problems with the next reaction in our lab. As you can see, is the sulfonylation of an indole in which we use NaH (60% dispersion in mineral oil) as a base. This reaction goes with ...
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