Linked Questions
10 questions linked to/from Addition of hydrogen bromide to 1,3-butadiene: thermodynamic and kinetic control
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What is the major product of the reaction of 2-methylbuta-1,3-diene with HBr? [duplicate]
What is the product of the reaction of 2-methylbuta-1,3-diene (isoprene) with HBr?
What I understand is that carbon (2) will get a positive charge after protonation.
But after this, which should be ...
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In the addition of HBr to isoprene why does the less stable carbocation form? [duplicate]
According to me, the answer is B as the tertiary allylic carbocation should be more stable. But the answer given is D and in the given solution, the tertiary allylic carbocation rearranges to primary ...
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What is the difference between ∆G and ∆G°?
In Brady's Molecular Nature of Matter, I read that $\Delta_\mathrm{r} G^{\circ}$ is $\Delta_\mathrm{r} G$ at $25~^\circ\mathrm{C}$. But later, it gives a value for $\Delta_\mathrm{r} G^\circ$ at ...
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Thermodynamic and kinetic products - carbocation stability
The professor wants to know which is the thermodynamic product and which is the kinetic product.
He says there are only two products - the two on the right that result from the resonance-stabilized ...
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What is proximity effect?
From Klein's Organic chemistry [1, p. 780]:
The 1,2-adduct is believed to form more rapidly as a result of a proximity effect. Specifically, the carbocation and the bromide ion are initially very ...
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Kinetic vs thermodynamic control of HBr to 1,3-Butadiene
The author claims that the transition state leading to the formation of the 1,2 product from the allylic carbocation is lower in energy since the carbon (which is attached to Br in the 1,2 product) is ...
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When 3,4-dimethyl-2,4-hexadiene reacts with HBr what is the major product?
I found out from drawing it out that there are 2 products: 4-bromo-3,4-dimethyl-2-hexene and 2-bromo-3,4-dimethyl-3-hexene. I want to know which forms most of the time.
I used the fact in allyl ...
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Formation of symmetrical ether or dehydration of primary alcohol?
My textbook gives the formation of diethyl ether from dehydration of ethyl alcohol:
$\ce{\underset{\text{ethyl alcohol}}{2C2H5-OH} ->[\text{conc.} H2SO4][413~K] \underset{\text{diethyl ether}}{...
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Why is the activation energy for 1,2-addition less than that for 1,4-addition to conjugated dienes?
1,2-addition proceeds faster than 1,4 addition making excess of 1,2-adduct at low temperatures. Also, since conversion of 1,2-adduct to 1,4-adduct is faster than the reverse, 1,4-adduct is in excess ...
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What is the major product formed when you react 1,3-butadiene with HBr in the presence of both ROOR and heat? [duplicate]
I just had an exam where we were given 1,3-butadiene as our reactant and our major product as 1-bromo-2-butene, where we had to state what the reagent was for that particular reaction. I stated that ...
