Questions tagged [allenes]
Use for question regarding the structure and properties of compounds containing a sequence of two cumulated double bonds.
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Synthesis of alkynes by double dehydrohalogenation; don't allenes also form?
So I was randomly looking at some really random exercises and I stumbled across synthesis of propyne from given compounds. There was $\ce{CH3CHBrCH2Br}$ as my substrate and I had to propose a way of ...
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Does a chiral allene have stereogenic centres?
This a picture of what my professor taught in class.
According the the definition of a stereogenic centre, allene should have two of them. So I don't understand what I am interpreting wrong.
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Can allenes be used as motors or generators?
I was thinking about an allene, fucoxanthin:
Potentially, we can draw a resonance structure in which up to eight of the carbon-carbon double bonds have moved one position to the left, a carbocation ...
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Does 1,3-dichloroallene possess a C2 symmetry axis?
Is there an $C_2$ axis of symmetry in $\ce{Cl-CH=C=CH-Cl}$?
A $C_2$ axis of symmetry means that I should be able to rotate the molecule about an axis by $180^\circ$. But I would need a composition ...
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Mechanism of synthesis of allene
I would like to know the mechanism of this reaction. In my first attempt to the question, I had replaced the two $\ce{Br}$s by $\ce{CH3}$s by $\ce{S_N2}$ of the organometallic compound but the answer ...
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Do allenes form rings?
I was wondering whether allenes can form rings; geometrically speaking, this seems like it would be energetically unfavorable due to their 180 degree linear geometry.
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How to calculate the number of geometrical isomers in allenes?
Can someone explain how to calculate the number of geometrical isomers in allenes like $\ce{CH3-(CH=CH)4-CH3}$ or $\ce{CH3-(CH=CH)5-CH3}$
user14857
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What is the hybridization of the central carbon in buta‐1,2‐diene?
State the hybridisation of asterisked carbon in $\ce{CH3-CH=\overset{\ast}{C}=CH2}.$
I am not sure between $\mathrm{sp^2}$ and $\mathrm{sp}$ hybridization. Because of the presence of double bonds I ...
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Stability of Allenes and Alkynes,
In Allenes, the $\ce{C=C=C}$ structure makes sure that the $p$-orbital of central carbon overlaps with 2 other carbons and the $p$-orbital of central carbon spreads out over the 3 carbons.
In ...
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Why are allenes chiral?
How is 1-bromo-3-chloropropa-1,2-diene ($\ce{BrHC=C=CHCl}$) chiral? It doesn't have any carbon that is connected to four different groups.
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