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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Accidental hydrolysis of tert-butyl chloride
Yesterday, I performed the synthesis of tert-butyl chloride from tert-butyl alcohole in my practical organic chemistry class. However, I only obtained a relatively low yield of about 30 %. Since I ...
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What is the maximum amount of carbon atoms that can comprise a fullerene?
As the fullerene sum formula can be defined as $\ce{C_n}$ with $n$ being any even integer number, is there any fundamental theoretical limit as to how big $n$ can get?
If there is no limit to the ...
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pKa of the alpha proton of an alpha amino ester [closed]
Is there a theoretical pKa value for the proton on the alpha carbon of a methylated amino acid, or just a general alpha amino methyl ester?
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Degradation of Pd catalyst in Buchwald-Hartwig amination
I am conducting Buchwald-Hartwig amination. I use $\ce{Pd_2(dba)3}$ and $\ce{P(o-tol)_3}$ as catalyst and toluene as solvent. Temperature is 100 ℃ and reaction time is 24 hours. During the reaction, ...
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Does the Oxy or Alkoxy Claisen Rearrangement Exist?
@Waylander's cogent Comment to the query of @Random Guy inspired me to post a problem in synthesis to test a question I have pondered for some time. The activation energy (AE) for the Cope ...
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Can amide form Schiff base?
Can amide ($\ce{RCONH2}$) form Schiff base? When I searched for it, most papers deal with aliphatic amines. Some paper conducted synthesis with amide-containing compound, but iminization occured at β-...
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Struggling to make SMCC
I have attempted to synthesize SMCC (succinimidyl 4-(N-maleimidomethyl)cyclohexane-1-carboxylate) following the lit protocol in J. Org. Chem. 2011, 76, 21, 9169–9174. Except for the scale, I followed ...
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How can we synthesize this cycloester, starting with methyl 4-phenylbutanoate?
I was wondering how to realize following synthesis:
I am struggling with this one; for sure, this has something to do with the benzyl position which is particularly reactive, and something ...
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Synthesis of allylic ether, starting with phenalene
I stumbled across a retro-synthesis question, for which I don't know the exact answer; I prepared two synthesis ways, but I don't know if they could be realized in a lab. The question is the following:...
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Reason for adding TFAA in this synthesis pathway?
I have included a short part from a synthetic pathway from: https://synarchive.com/syn/112
$\ce{Mg3N2}$ reacts with $\ce{MeOH}$ to liberate $\ce{NH3}$ which I believe is used in nucleophilic ...
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Reasons for scratching the wall of a flask when precipitate crystals [closed]
I heard that scratching the wall of the flask helps precipitate crystals when obtaining crystals.
By scratching the wall of the flask, the crystals from it fall in the center and act as seeds to help ...
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How can we synthesize 1,1-dichloro-2,2,3,3-tetramethylcyclopropane from pivaldehyde?
How to synthesize 1,1-dichloro-2,2,3,3-tetramethylcyclopropane from pivaldehyde? I don't know how to close the ring structure:
Should we synthesize an epoxide first? I'd appreciate any tips regarding ...
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Side-chain Oxidation vs Oxidative Cleavage
When the above compound is subjected to acidified $\ce{KMnO4}$, can both side chain oxidation and oxidative cleavage of $\ce{C=C}$ bond occur? Or will one have priority over the other?
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Method to remove impurities from acetaminophen synthesis experiment
I'd like to know about impurities from acetaminophen synthesis experiment. Are there any impurities produced by oxidation of p-aminophenol? If there is any impurity produced by oxidation of p-...
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1answer
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What is the maximum length of peptide which considered to be hard for synthesis by the current technology?
I am a molecular biologist and work with recombinant proteins. I am wondering what the cut point, in terms of length, is at which I should produce the peptide using heterologous expression rather than ...
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Differences in activated manganese dioxide synthesis
I've looked into preparations of activated manganese dioxide for some time now, and what confused me is the contrast between the original Attenborough method and some of the alternatives.
A solution ...
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Can two two-material composite precipitation methods be used to make one three-material composite?
There are many methods used in the synthesis of cellulose nanocomposites, including Fe₃O₄@Cellulose in urea, ammonia, and water solution and immersing the product in sulfuric acid, or somewhat ...
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1answer
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Sodium acetate stoichiometry from baking soda and vinegar
I want to make sodium acetate from sodium bicarbonate and vinegar. I'm a bit stumped at calculating amounts of each reagent. I'm starting with 8% acetic acid vinegar. I was going to add, to 1 L of the ...
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431 views
Choosing reaction stoichiometry in organic synthesis
Reading papers about organic synthesis, I see many cases like setting one material as 1.2 eq. I presume that reagents used more than 1 equiv are relatively inexpensive or less reactive than other ...
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Problem about TLC solvent and staining
I am conducting an organic synthesis involving 1-aza-18-crown-6-ether. I tried TLC, but they didn't work well. I have tried: (1) hexane+ethyl acetate in various ratio, (2) dichloromethane:methanol=3:1,...
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1answer
55 views
Setting up reactor in inert atmosphere
I am searching for reactor set-up that can maintain inert atmosphere, and found that many organic synthesis labs use Schlenk line. But organic synthesis is not main thing of my lab, so there is some ...
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Synthesis of active chemical manganese dioxide (CMD) for primary alcohol oxidation
This paper1 uses chemical manganese dioxide (CMD) instead of activated manganese dioxide for mild alcohol oxidation. I'm looking for a route on how to synthesize active CMD. Could this work?
$$\ce{...
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2-Iodoxybenzoic acid oxidation reaction
I was thinking about using 2-Iodoxybenzoic acid to selectively oxidize primary alcohols to aldehydes. I've found papers using various solvents like acetone/water mixture1, 2-methyl-2-propanol2, DMSO ...
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How can I make cerium(IV) chloride? [closed]
How can I make CeCl4?
I have some ideas but am worried I'm going to mess it up since this is the first time I've worked with lanthanides.
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2answers
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Decarboxylation of primary amino acids
Since primary amino acids like glycine, alanine can't be decarboxylated under oxidative conditions, what would be the best catalyst for this reaction?
I was thinking about copying decarboxylases with $...
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1answer
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Can I synthesize potassium hydroxide from readily available materials?
Where I live, KOH is not readily available and is cost prohibitive to ship. A number of other materials are available, however. I have read similar questions and their answers here, but most are too ...
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1answer
56 views
Making bioplastic at high school level chemistry using PLA/Starch blends
I'm currently working on a high school chemistry essay about biodegradable plastics. I know that there is an easy way to synthesize Thermoplastic Starch (TPS), a starch-based bioplastic using glycerol ...
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362 views
How is 3-bromocyclohexene converted to cyclohexane?
My attempt is illustrated below:
or
Which of these methods is most viable?
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Can you develop algorithms to predict synthesis of peptides?
This may be a very foolish question, but do (complex) algorithms exist to predict the steps and materials involved (or therefore different options and paths) in synthesis for the given input of for ...
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1answer
74 views
Is it possible to filter Stille catalysts using syringe filter?
I'm conducting an organic synthesis involving Stille coupling.
Stille coupling uses $\ce{Pd2(dba)3}$ and $\ce{P(o-tol)3}$ as catalysts.
Both catalysts dissolves in toluene which is the solvent of my ...
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1answer
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In solid-phase peptide synthesis, why are the formation of aspartimides a problem but not "glutamides"?
I'm studying solid-phase peptide synthesis (SPPS) at the moment, and a common problem is the formation of aspartimides, which disrupt the synthetic process.
I understand how they form and why are they ...
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About the Vilsmeier-Haack formylation of this compound
I was reading an article and found the following reaction sequence:
The second step involves a formylation of the hydrazone with the Vilsmeier reagent to, first synthesize the pyrazole ring and then, ...
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1answer
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Synthesis of (1S,2S,4S)-4-ethenyl-5-methylcyclohexane-1,2-diol
I'm trying to devise a synthesis for the following question.
I am aware it involves retrosynthetic, Wittig, Grignard and diels alder reactions, but unfortunately I can't really grasp all concepts ...
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Making a bridge on a cyclic molecule
So, my question is how would I make a bridge as seen on the following molecule (right side)?
As for the molecule on the left, I am supposed to make it using that molecule as a base. The only ...
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1answer
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Synthesis of diethyloxalate from ethene
Outline the steps involved in the following transformation: $\ce{C2H4}$ to $\ce{(COOC2H5)2}$ (diethyl oxalate).
I am familiar with the transformation of $\ce{C2H4}$ to ethyl acetate $\ce{CH3COOC2H5}$ ...
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1answer
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Mechanism for Diels–Alder of alkene with substituted thiophene sulfone with loss of sulfur dioxide
I came across a synthesis of centrohexaindane that has the following steps:
This is a Diels–Alder reaction that gives an aromatic ring. I know that alkynes will give this reaction as follows:
But in ...
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1answer
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Coordination complex - nitrito-N & nitrito-O
I am currently learning the coordination compounds and encountered a new isomerism called linkage isomerism.
I am thinking that if I want to get some $\ce{[Co(NO2)6]^3-}$, I should have to dissolve $\...
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1answer
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Synthesis of 1-naphthaleneacetic acid: Methods
I am trying to synthesizing 1-naphthaleneacetic acid from naphthalene and monochloroacetic acid. I found some patents and papers, and I have tried to synthesis but the yield is low. I used iron powder ...
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How can I weigh the compound that melts at room temperature?
I am conducting an organic synthesis experiment involving 2,3,5-tribromothiophene.
The melting point of 2,3,5-tribromothiophene is about 25-28 ℃, so it melts easily during weighing.
Whenever I weigh ...
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Procedure for laboratory synthesis of tertiary amines [closed]
I am having difficulty finding a procedure for making tertiary amines in the lab, any is fine but I am specifically interested in tributylamine.
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1answer
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Carbon 11 radiolabeled inhaled Beta-2 agonist or corticosteroids, is it possible?
Background
Positron emission tomography (PET) is a highly sensitive imaging modality that can provide in vivo quantitative information of biological processes at a biochemical level. PET relies upon ...
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2answers
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What type of reaction is this? (Modified organic nucleoside synthesis)
What type of reaction is shown in step F of this patent image?
I tried looking it up in SciFinder, but I didn't get any results, and I have not seen this before.
Thank you!
Edit 1: I'm also wondering ...
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1answer
65 views
How to make silicic acid, potassium silicate or calcium silicate?
I am a student of tropical agriculture. I am taking the class of agronomic chemistry and plant nutrition. I want to make use of silicate source I have at home for e.g. zeolite, wood ashes, ...
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2answers
430 views
Hydrolysis of nitriles: Amide vs Carboxylic acid
I was recently studying the preparation of amides,and one of the methods listed was acid hydrolysis of a nitrile. Up until now I thought acid hydrolysis of nitriles yielded carboxylic acids. How are ...
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Alkylation of enolates using tertiary halide
I was recently studying the alpha alkylation of enolates using LDA followed by subsequent treatment with primary halides to give the product.I was wondering what happens with teritary halides. My ...
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Alpha-haloketone reaction with H2O in acid medium
I need help with this reaction, I know that in the first step an alpha haloketone is formed, but I can't figure out what reaction is going to happen between the alpha Haloketone and $\ce{H2O/H+}$.
I ...
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Can the guanidinium ion give stable N-nitrosamines under mild metalworking conditions?
Can the guanidinium ion react with inorganic nitrite under mild basic metalworking conditions ($\mathrm{pH\ 8 - 10}$ and temperature $\lt \pu{70^\circ C}$) to give stable N-nitrosamines?
Usually, the ...
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The things you wish you would have done before doing a PhD in Organic Chemistry? [closed]
Hello there fellow chemists. I am really interested in doing a PhD in Organic chemistry. I haven't really thought which field I would like to specialize in, but it's definitely on my mind ever since ...
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Examples to show how useful or not useful of dimerization, trimerization, tetramerization and their likes in synthesizing alkenes and other compounds?
this answer shows that dimerization is a synthetic method
On wikipedia, 1-octene is showed to made from numerous dimerizations or a tetramerization.
When I read that piperazine $\ce{C4H10N2}$ is made ...
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Chemically producing sodium metal from magnesium
Anyone with experience making sodium metal ($\ce{Na}$) with the following process? Reactants: $\pu{14 g}$ magnesium powder, $\pu{20 g}$ sodium hydroxide; Catalysts: $1$ to $\pu{2 g}$ menthol crystals; ...
