Questions tagged [organosilicon-compounds]
For questions about organo-silicon compounds, chemical, physical, and optical properties.
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How long can a silicone and white spirit solution be stored without hardening?
I’ve heard that some people use a mixture of silicone and white spirit to waterproof their gear.
How long this solution can be stored without hardening if it is stored in a closed hermetic bottle?
If ...
3
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1
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Nomenclature of tertiary amine derivative
I’m experiencing difficulties putting together a full name of the tertiary amine. One substituent is propyltrimethoxysilane $\ce{(OEt)3Si-CH2-CH2-CH2\bond{-}}$, and the two others are ...
3
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How to adjust selectivity of gas-permeable PDMS membranes for environmental applications?
I have an idea about making an environmental sensor that uses a gas-permeable membrane (GMP) and how its probe could be submerged in a water source with an off the shelf gas sensor.
So far, my ...
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1
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What would the mechanism be for intermediate B to Supinidine, and what would by product C be? [closed]
I have managed to do the mechanism for the first step, but have no clue how 4 equivalents of MeLi are used for the second step of the reaction.
0
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Data on Vapour Pressures of Silicone Oils [closed]
I am trying to find specific information on vapour pressure of silicone oils with different viscosities which I have used in some experimental work. Is there a chemical databook where this information ...
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0
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How to remove starch from silicone ("Oogoo")?
Oogoo is an easy and cheap way of creating silicone rubber objects from a hand-formable putty. Basically: just mix silicone caulk with starch (I'm using acetate moisture absorbing silicone caulking ...
3
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1
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106
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Siiloxane polymer experiment
I believe the first reaction would be a substitution of $\ce{SiMe3}$ for $\ce{I}$ and creating $\ce{SiMe3Cl}$.
The second process I think would involve the $\ce{Mg}$ removing the two $\ce{Cl}$ and ...
4
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0
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367
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Mechanism for removal of trimethylsilyl directly bonded to carbons
I recently came across a scheme for the synthesis of panacene (Sabot et al., 2008OrgLett4629):
In this synthesis, the step from 14 to 9 in removes a trimethylsilyl ($\ce{TMS}$) group directly bonded ...
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0
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Selectivity in Thermodynamically-Driven Silyl Enol Ether Formation, and Optimistic Avoidance of Protecting Group Chemistry
I am aware of the regioselectivity of silyl enol ether formation at an unsymmetrical ketone under 'thermodynamic conditions'.
Does this selectivity extend to systems containing more than one ketone ...
3
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1
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White growth on unopened bottle of chlorotrimethylsilane
I have a white, moldy-like substance that has been growing near the cap of an unopened glass container filled with TMSCl. It has spread to form a thin, powdery coating on all of the other containers ...
0
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How is silicic acid formed?
My book gives the following reaction:
$$\ce{SiCl4 + H2O -> HCl + Si(OH)4}$$
Since equilibrium favours the formation of weaker acids. How is this reaction able to proceed if a strong acid like HCl ...
1
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1
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What is the density of sodium trimethylsilylpropanesulfonate (DSS)?
I tried to look for the density of sodium trimethylsilylpropanesulfonate (DSS) online but could not find anything. Perhaps someone here measured it/knows where it may be found?
3
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Can PDMS silicone be produced with dichloromethane?
I was taking a simulated admission test for a Technology Institute (Brazilian ITA) and one of the questions asked for the production of PDMS silicone via these described steps:
Reaction of $\ce{SiO2}$...
9
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1
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What is nowadays called silazane?
Example from the Recommendations 2013. Left: Alleged disilazane ; Right: My version
Clearer example without obvious flaws in alternative structure. Left: Alleged disilazane ; Right: My version
I am ...
3
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Easy way to derivatize silsesquioxanes
I have a polymer end-capped with a polysilsesquioxane (POSS) like this one $(\ce{R} = \ce{i-Bu})$:
I haven't found much info on what type or reactions these POSS groups can undergo. Are there any ...
4
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2
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Can Silicon be used as anode for Li-Ion batteries
Can Si be used as anode. I assume you could store much more energy in Si since the atom is much larger than C, but then Si seems not to like to bond with itself. Can there be a solution?
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Deposition of Nb on SiO2 wafer (Z-Cut)
I am trying to sputter $\ce{Nb}$ on $\ce{SiO2}$ Z-Cut wafers (quartz crystal). I was wondering if $\ce{Nb}$ will stick well to the surface of the wafer.
I've routinely deposited $\ce{Nb}$ on $\ce{...
2
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1
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how to manufacture PTC ink
I am trying to create a PTC ink similar to Henkel ECI8120 , I researched PTC rubber and found that it was Polydimethylsiloxane (PDMS) loaded carbon nanoparticles, I was wondering if anyone here has ...
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Is the reaction of SiC and H2O a redox reaction?
In the reaction: $$\ce{SiC + 2H2O <=> SiO2 + CH4}$$ The oxidation state of Si is +4 in both SiC and SiO2, while the oxidation state of carbon is -4 in both SiC and CH4 (confirmed by this).
Here ...
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Does "silica colloidal anhydrous" contain aluminium?
Some silicas such as sodium aluminosilicate contain aluminium. Is silica colloidal anhydrous one of these substances?
12
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2
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Why is trimethylsilanol a stronger acid than tert-butanol?
The Wikipedia article about trimethylsilanol says the following:
Trimethylsilanol is a weak acid with a $\mathrm{p}K_\mathrm{a}$ value of 11. The acidity is comparable to that of orthosilicic acid, ...
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Selective sorption of toxins by polymethylsiloxane polyhydrate
Polymethylsiloxane polyhydrate (PMSPH) is used as enterosorbent for a couple of decades (nowadays under the trademark "Enterosgel"), intended for binding in the gastrointestinal tract and excretion of ...
7
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2
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Stabilisation of anions by silicon
In my lecture notes it was stated that in $\ce{Me3SiCH2SMe}$, deprotonation with tBuLi generates an anion in between Si and S. I've been not able to find the $\mathrm pK_\mathrm a$ values (not listed ...
2
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What does the number mean in Sylgard 170, Sylgard 184, etc?
My lab uses a lot of PDMS, a silicon-based organic polymer, to make microfluidic devices. PDMS is available in many different formulations, and we usually use Dow Corning's Sylgard 184. Recently we ...
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Decrease in Surface area leads to Increase in load capacity for mesoporous material?
So at the bottom of page 86 it says that when SBA-15 is functionalized with Glutaraldehyde it results in a substantial decrease in the surface area and pore diameter of the mesoporous material.
This ...
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1
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219
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Is there a silicon equivalent to a carboxylic acid?
Can terminal Si on a siloxane chain have double bond O and OH?
3
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Cycloaddition of Silyl Dienol Ethers with Sodium Bromodifluoroacetate: What's the scope?
I have recently came across this article "Copper(I)-Catalyzed [4 + 1] Cycloaddition of Silyl Dienol Ethers with Sodium Bromodifluoroacetate: Access to
β,β‐Difluorocyclopentanone Derivatives". (Org. ...
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Competitive 'Wittig' vs 'Peterson' C=C bond formation
If one considers the intermediate above, there are immediately two possibilities for subsequent reaction:
1. A Wittig-type olefination which would lead to a vinyl silane: This reaction happens to be ...
8
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2
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Removal of tetrabutylammonium from an organic reaction
I need to synthesize some organic compound for my Ph.D. research. Everything went OK during the synthetic route but got messed up at the very end. In my final step (once the final compound has been ...
2
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1
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Why are silyl chlorides more readily hydrolysed than alkyl chlorides?
I know that the $\ce{Si-Cl}$ bond has a slightly higher energy, but silyl chlorides are much more readily hydrolyzed compared to alkyl chlorides. I do not fully understand why that is. My thoughts so ...
7
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How can the bulky octadecyltriethoxysilane molecule promote single-crystal growth?
Octadecyltriethoxysilane is very bulky (source),
yet it was used to promote single crystal growth (source). How can such a bulky molecule induce crystal growth? (For example epitaxial growth happens ...
16
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1
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By what mechanism do acids deprotect primary silyl ethers?
Standard protocols report the selective deprotection of primary silyl ethers in the presence of secondary silyl ethers under acidic conditions, as exemplary shown in scheme 1, a reaction by Hartmann ...