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According to Paul Sabatier in "Catalysis in Organic Chemistry", With ethyl alcohol [on alumina], ether is formed above 240° and at 290° pure ethylene is evolved regularly, this evolution becoming rapid at 340°. so at 250°C the product should be primarily diethyl ether. I don't think "excess" has the normal organic chemistry meaning in ...

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I think the alloy is used to give a melting range ( 200 to 300 C) rather than a melting point ( 231 C) for pure tin. The zinc might reduce oxygen in the melt but I doubt it can breakdown aluminum oxide to clean the surface.

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The first eq. of MeLi deprotonates the alcohol. This does not cyclise as it would form a 7-membered ring and that is not strongly favoured. The subsequent eqs of MeLi remove the methyl carbamate group as described by Sawyer, et al., by consecutive additions of Me to give first the N-acetamide then the amine anion plus acetone. The N anion cyclises onto the ...

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In such a reaction, the oxidation number are not modified. This dissolution is not a redox reaction. It will not produce $\ce{Cl2}$ and $\ce{UO2}$ (as stated by Young), which would imply an oxidation of Chlorine by Uranium. To find the equation, consider that autunite is made of the following ions : \ce{Ca(UO2)2(PO4)2 -> Ca^{2+} + 2 UO2^{2+} + 2 PO4^{3-}...

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I am going to post my own answer since now I have figured it out in much more detail based on the answer I had accepted above. I don't have the PDB file of the lactose synthase model above, but I was since steered to use LDH. And here is the author's picture from Cook, Senkovich, et al. Biochemical and structural characterization of Cryptosporidium parvum ...

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Your question stays fuzzy, and the addition of the scheme does not add much clarification. The arrow between mesomers is not the one about a reaction, nor about a chemical equilibrium. (Typically, R and R' designate substituents at the periphery of a chain, or a cyclic core structure; but not about what different spaces within a chain. This just as a side ...

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Yes, $\ce{FeCl3}$ is a well known Lewis acid that is used in place of $\ce{AlCl3}$ for FC reaction. See the paper linked by user55119 and also this question. Other $\ce{MX_n}$ types of reagents used in FC reactions are $\ce{BF3}$, $\ce{BeCl2}$, $\ce{TiCl4}$, $\ce{SbCl5}$, $\ce{SnCl4}$, $\ce{SeCl4}$, $\ce{TeCl4}$, $\ce{InCl3}$, $\ce{NbCl5}$, $\ce{IrCl3}$ or $\... 2 Having had no responses to this post, I thought I would offer a scheme in an effort to answer the question about the existence of the oxy Claisen rearrangement. α-Diketone 1[1] was chosen as a starting material owing to the equivalency of the two carbonyls. Selective monoketalization of α-diketone 1 with β-bromoethanol affords cyclohexanone 2. Over ... 7 For any pericyclic reaction (including cycloadditions), the key set of rules are the Woodward–Hoffmann rules. The rules are actually quite general, but people often first learn about them in the specific context of cycloadditions*: Cycloadditions involving$4n$π-electrons ($n$being an integer) proceed photochemically. Cycloadditions involving$4n + 2\$ π-...

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The reaction can be safely assumed to be an SN1 reaction since, the solvent (aqueous C2H5OH, which is the nucleophile as well) is a polar species. (2) shall yield a tertiary carbocation and (3) shall yield a secondary carbocation by the cleavage of the carbon-halogen (C-Br) bond. However, in case of (1) cleavage of the said bond to yield a carbocation would ...

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The image shown in the question can be found with some context at https://www.open.edu/openlearn/science-maths-technology/science/chemistry/introduction-polymers/content-section-4.3.3 In that document, they say of chain transfer: A similar mechanism accounts for the side branches in LDPE where it is a more important mode of termination than in polystyrene ...

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When an enzymatic reaction is studied using X-ray crystallography, there are multiple structures that provide information: The apo-enzyme (empty active site) Enzyme with inhibitor in the active site Product complex Substrate complex Of those four types, (4) is often the most difficult to achieve. The first enzyme studyied by crystallography, lysozyme, ...

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The relevant PDB file is probably 1j8x because it contains both the carbohydrate and the nucleotide shown bound in the active site in the image the OP provided. You could use Jmol, e.g. at https://chemapps.stolaf.edu/jmol/jsmol/simple.htm to convert to a 3D molfile. Here are the commands set pdbAddHydrogens true adds hydrogens and double bonds upon loading ...

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Although, the Mozingo reaction, which describes the hydrogenolysis of Sulfur compounds by Raney nickel catalyst, is discovered in 1943 (Ref.1), the removal of sulfur from an organic molecule using Raney nickel is known even before. For example, the traces of catalyst poisons (mostly sulfur containing compounds) may be removed by treating compounds ...

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