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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What's simulation freeware for polymer synthesis better? [on hold]
I am studying master research program to learn polymer synthesis, now I would like to enquire anyone to introduce what open resources of simulation software for polymer synthesis can help analyse ...
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1answer
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How is chlorocarbene synthetised?
The wikipedia page on cyclononatetraene says that the aromatic cyclononatetraenyl anion can be synthetised by a rearangement of 9-chlorobicyclo[6.1.0]nona-2,4,6-triene.
My first idea on how to ...
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How to synthesize 2-chloro-3-formyl quinoline in lab? [closed]
I am trying to synthesis 2-chloro-3-formylquinoline from reported Vilsemier-Haack reaction. N,N-Dimethylformamide ($\pu{0.025 mol}$) was cooled in an ice-salt bath and treated with phosphoryl chloride ...
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Can antimony pentafluoride be made by adding hydrogen fluoride to antimony trifluoride?
I was looking at how the strongest acid was made and I found something I did not understand. On the Wikipedia page for antimony trifluoride it shows the production of $\ce{SbF3}$ using $\ce{HF}$:
$$\...
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How to improve efficiency of the diamine synthesis from fluorescein?
In this work, fluorescein was incorporated with an equal molar of 1-chloro-4-nitrobenzene and double potassium carbonate (molar ratio), the solvent of this reaction is dimethylacetamide (50 ml for 5 g ...
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How would one carboxylate CBG into its acid form, CBGA?
I have a project that would require cannabigerolic acid (CBGA) as a synthase substrate, but the only available chemical I can find is cannabigerol (CBG). CBG is the product of CBGA through ...
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What is the mechanism of the reaction of ethyl prop-2-ynoate to ethyl (2Z)-2,3-dibromoprop-2-enoate?
It's really weird for the product is 99％ Z-comformation?
Please tell me why?
This reaction can be found in scifinder.
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Synthesis for turning synephrenine into N-methylphenethylamine
I am trying to devise a synthesis to change synephrine (4-[1-hydroxy-2-(methylamino)ethyl]phenol) into N-methylphenethylamine.
I was figuring that I could remove the hydroxyl group attached to the ...
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2answers
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What reagents or series of reactions would allow for selective hydroxylation of an allylic methyl group outside of a ring?
Sample transformation for selective hydroxylation of an allylic methyl group outside of a ring. Selenium dioxide would not work since hydroxylation would be favored inside the ring.
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How to convert -OH to terminal -SH group in nucleolipids: [closed]
I am recently working on some synthesis of Nucleolipids and I want to transform $\ce{-OH}$ to terminal $\ce{S}$ group.
Can anyone help?
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What is the standard way to know the price of a chemical substance? [closed]
I've encountered many vendors with broadly varying prices for the same chemical substance, including amazon and Alibaba. I wonder if there is a standard way to know the universal/average price of a ...
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Could you form quartz crystals by melting and cooling sand very slowly?
Since glass is amorphous quartz and when you slow the cooling of something enough it will crystallize, couldn’t you melt $\ce{SiO2}$ (sand) and then very slowly cool it to cause spontaneous nucleation ...
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IrO2 (iridium oxide) synthesis [closed]
How do I synthesize $\ce{IrO2}$ from $\ce{IrCl3}$ ? Please suggest a least expensive method.
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Aldol Reaction in Water Not Working
I am conducting an Aldol formation reaction in water, and below is the experimental protocol I am following (from J. Org. Chem. 1994, 59, 3590—3596):
Formation of Aldol in Water using Yb(OTf)3 ...
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A broad singlet at 2.27 ppm?
I took the $\mathrm{^{1}H}$-NMR (CDCl3 solvent) of my product, 2,2-dimethoxy acetic acid. Below is what I see:
$\delta \: \pu{4.862 ppm}$ (1H), $\delta \: \pu{3.521 ppm}$ (6.78H), $\delta \: \pu{2....
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1answer
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Purification of Solid Phase Synthesized Peptide
I began working in a newly setup lab, and I'm having a dilysine (K2) peptide synthesized by solid phase method. I plan to cleave the peptides from the resin with a cleavage cocktail of TFA. ...
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Synthesis of anthranilic acid
Yesterday, I performed the synthesis of anthranilic acid (also known as, 2-aminobenzoic acid. I was instructed to use the common route that is also featured on the Wikipedia page for this compound. ...
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Reagents for synthesis of ethyl 2-(2,3-dihydrobenzofuran-2-yl)acetate from naphthalen-1(4H)-one
The following conversion can be performed in a few steps. Show key intermediates and reagents (detailed mechanisms are not required).
So I've been looking at this for a while and I can't seem ...
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PLGA - poly(lactic-co-glycolic acid) Synthesis
Does anyone have experience with the synthesis of PLGA? PLGA is synthesized by means of ring-opening co-polymerization of two different monomers, the cyclic dimers (1,4-dioxane-2,5-diones) of ...
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Substitution / Elimination competition
I am trying the hypothetical synthesis below, but I didn't get the product I was expecting. Instead, the reaction formed mostly styrene, in >80% yield (elimination product of the bromide)
The ...
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1answer
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Why is molybdenum that important in inorganic synthesis as well as biosynthesis of ammonia?
We know that Mo (Molybdenum ) is used as a catalyst for Haber's process, during synthesis of Ammonia from Nitrogen. Again, in biological systems, Nitrogen fixation (ALSO forming Ammonia from Nitrogen)...
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2answers
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Synthetic steps for the interconversion between aldehydes and ketones
I am learning about carbonyl chemistry at the moment. So far, we have been able to make aldehydes and ketones from alcohols (via oxidizing agents). I can't help but wonder if there is possibly any way ...
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What's the purpose of stirring the mixture at 0 degree and dding NaOH to the organic reaction mixture?
I used to follow the lab protocol without thinking, but I now hope to understand why certain procedures are done.
I am synthesizing dimethoxyacetic acid from methyl dimethoxy acetate(so hydrolysis ...
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1answer
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Synthesis of a weinreb amide from an acid
The following shows the conversion of an acid to a weinreb amide:
It was taken from the IChO 2015 preparatory problem set problem 23. In this two-step synthesis, I am slighly puzzled by the first ...
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How to acetylate a thiol group in general?
I wonder (and have tried to find the answer by searching in synthetic chemistry resources) how do you acetylate thiol (R-SH) groups in general? For example the cysteine-SH group either alone to make S-...
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2answers
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Finding all Chemical Reactions Given Products and Reactants
Suppose only a set of chemical formulas is given. How can you find all mathematically possible chemical equations whose educts and products are only from this set?
Take e.g. the set $\{ \ce{C, H2, O2,...
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t-Boc protection of amide (urea)
I'm trying to prepare protected urea and I'd like to protect it with some alkali stable PG. Is it possible to protect urea with t-Boc? Or is there another way to get boc-protected urea?
3
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1answer
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What is the mechanism of azulene synthesis?
In the Organic Syntheses preparation of azulene (http://www.orgsyn.org/demo.aspx?prep=CV7P0015) there are two reactions. First is a clevage of the C-N bond in pyridine and the second one is the ...
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1answer
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Preference for basic conditions in ester hydrolysis
It has occurred to me that it is very common see the use of basic conditions for ester hydrolysis in various syntheses. One such sequence commonly seen in the case of the malonic ester synthesis is:
$...
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What takes place in this transformation of the 1,3-dicarbonyl?
I was just looking at a particular synthesis method on the Organic Chemistry Portal when I saw a particularly puzzling step, involving a 1,3-dicarbonyl compound. The step which I am puzzled by is ...
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Monitoring amino acid esterification
I am trying to monitor the esterification of a non UV active amino acid.I used thionyl chloride and Methanol as reagents.
As amino group is unprotected, Ninhydrin should give positive result for both ...
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1answer
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Effect of substituents on Ullmann reaction
This question that I recently encountered asked what the most suitable substrate for the Ullmann reaction would be. The answer given is (b) but I think it has to be (d) as the nitro group acts as EWG ...
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Why might the yield of my synthesis of triphenylmethanol be so poor?
I performed the classic Grignard reagent formation leading into the preparation and purification of triphenylmethanol using phenylmagnesium bromide as my Grignard, and benzophenone as the reagent for ...
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Why is phosphoric acid preferentially used for dehydrating alcohols during synthesis of alkenes?
I have also seen concentrated sulphuric acid being used, but what makes phosphoric acid preferable to sulfuric acid?
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1answer
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Why doesn't self condensation occur in acetoacetic ester synthesis
So, I came across a quite versatile method to synthesize aldehydes and ketones, its called the Acetoacetic ester synthesis.
Suppose I need some 2-pentanone. So to synthesize it via this method I can ...
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Production of L-glucose
What chain(s) of reactions are used to produce L-glucose? I did a search on Google scholar but to my surprise nothing came up. My guess would be that the synthesis starts from D-glucose for which ...
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1answer
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Opening the imidazoline ring in tolazoline
Hello.
I was studying about the alkaline ring opening or purines. While doing research, i came across this compound. This got me thinking if we can use the same procedure to open the imidazoline ring ...
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Changing the CO2 concentration (adding or subtracting) inside a sealed vessel?
I am looking for a method of modifying the CO2 concentration inside a sealed container that is both precise and repeatable (C02 needs adjustment every time the container is sealed, also need to be ...
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1answer
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ICHO Synthesis Problem 2018
I've several doubts about this ICHO synthesis problem, which was a part of the preparatory problem package of 2018 (so yes, it's not a part of an ongoing contest)
Before sharing the answer given, I'...
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2answers
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Cis Orientation of dienophiles orientation of groups maintained in Diels Alder
When I was reading about Diels-Alder reactions, I was confused about the cis and trans rules for dienophiles, as shown below.
The text told me that "a cis dienophile will generate a ring with cis ...
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1answer
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questions about the synthesis of iodobenzene from aniline
I am conducting an experiment about synthesis of iodobenzene from aniline, referring to this site(and various sites) (http://www.prepchem.com/synthesis-of-iodobenzene/). Below is my experimental ...
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1answer
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Can you make imines from Formaldehyde or Acetaldehyde?
Title says it all. Wondering if imine formation would work with an aldehyde, even better would be formaldehyde.
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Reaction between Salicylaldehyde and 2-Benzoylpyridine
In a paper by Sheng et al (10.1016/j.dyepig.2018.07.036) the authors synthesize the compound MZC as shown in the scheme below.
I'm looking for information about what the reaction mechanism is that ...
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1answer
103 views
How to remove MEHQ from Methacrylic acid monomer without reduced pressure distillation?
I am aware that the standard way to remove MEHQ from Methacrylic Acid is to perform reduced pressure distillation. The papers I see suggest using ~ 10 Torr pressure to perform distillation. Sandler's ...
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1answer
167 views
Can thiols be created using a Grignard reagent?
I'm trying to find information on the synthesis of thiols via Grignard reagents. While looking at the synthesis routes on Wikipedia, it said that a Grignard reagent will react with sulphur to form ...
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402 views
Converting phenol to para-nitrophenol via nitrosophenol
Our class 12 text book says that if we treat phenol with mixture of concentrated $\ce HNO_3$ and $\ce H_2SO_4$, instead of nitration, the ring is oxidized to quinone.
So, the book proposes that we ...
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1answer
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Synthesis of 3-(2-oxocyclohexyl)propanenitrile
Does this seem correct?
The point is to draw the mechanisnm of which 3-(2-oxocyclohexyl)propanenitrile is synthesized from 1-(cyclohex-1-en-1-yl)pyrrolidine.
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1answer
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Formation of (Gamma) Methylparaconic acid
I came across this question recently,
I tried to devise a mechanism but I'm struck here,
My try -
Moreover, I think my mechanism is somewhat inefficient because of formation of some byproducts, ...
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1answer
197 views
Why is ethanol distilled off before adding water?
I am doing a malonic synthesis shown below, and I wonder why I should distill ethanol off before adding water in the first step of the reaction (First I add absolute ethanol and solid sodium).
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1answer
121 views
How to predict ease of oxidation or reduction for a given oxidising or reducing agent? [closed]
I have never understood which agent will be able to oxidize or reduce which type of reactants and yield which type of products will be formed. For example I want to know about DIBAL-H and how is it ...
