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Major product of 2-iodopropane + sodium ethoxide
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Lance Chambers
Major product of 2-iodopropane + sodium ethoxide
That is a difficult question, because they are measured differently. Just for your own edification, how would you favor the SN2? How would you favor the E2?
That is a difficult question, because they are measured differently. Just for your own edification, how would you favor the SN2? How would you favor the E2?
It is a good nucleophile, too (consider the Williamson ether synthesis). I think that the choice of solvent and temperature affect the relative rates of the two reactions, but I am not certain by how much. Are you given any information about the solvent?
No, nor temperature. Is sodium ethoxide a better nucleophile than it is a base at standard conditions and in water?
It is a good nucleophile, too (consider the Williamson ether synthesis). I think that the choice of solvent and temperature affect the relative rates of the two reactions, but I am not certain by how much. Are you given any information about the solvent?
No, nor temperature. Is sodium ethoxide a better nucleophile than it is a base at standard conditions and in water?
I don't see how Zaitsev's rule comes into play when there is only one possible elimination product, but...
You're confusing me.
Zaitsev's rule is used if multiple products are available. But I don't see any other possible products from the information given (unless sodium ethoxide does something which I'm not aware of) and therefore, propene is just the major product?
I don't see how Zaitsev's rule comes into play when there is only one possible elimination product, but...
You're confusing me.
Zaitsev's rule is used if multiple products are available. But I don't see any other possible products from the information given (unless sodium ethoxide does something which I'm not aware of) and therefore, propene is just the major product?
It is a good nucleophile, too (consider the Williamson ether synthesis). I think that the choice of solvent and temperature affect the relative rates of the two reactions, but I am not certain by how much. Are you given any information about the solvent?
It is a good nucleophile, too (consider the Williamson ether synthesis). I think that the choice of solvent and temperature affect the relative rates of the two reactions, but I am not certain by how much. Are you given any information about the solvent?
I don't see how Zaitsev's rule comes into play when there is only one possible elimination product, but...
You're confusing me.
Zaitsev's rule is used if multiple products are available. But I don't see any other possible products from the information given (unless sodium ethoxide does something which I'm not aware of) and therefore, propene is just the major product?
I agree that there is only one elimination product. There is one other kind of reaction besides an elimination available to iodoalkanes.
Yeah, I got it. Sodium ethoxide can act as a nucleophile which allows for an SN2 reaction to occur. Since sodium ethoxide is a strong base and a relatively weaker nucleophile, then it is expected that the E2 product is the major product?
I don't see how Zaitsev's rule comes into play when there is only one possible elimination product, but...
You're confusing me.
Zaitsev's rule is used if multiple products are available. But I don't see any other possible products from the information given (unless sodium ethoxide does something which I'm not aware of) and therefore, propene is just the major product?
I agree that there is only one elimination product. There is one other kind of reaction besides an elimination available to iodoalkanes.
Yeah, I got it. Sodium ethoxide can act as a nucleophile which allows for an SN2 reaction to occur. Since sodium ethoxide is a strong base and a relatively weaker nucleophile, then it is expected that the E2 product is the major product?
Edit: Ah maybe a substitution could occur since sodium ethoxide can function as a nucleophile ... the question is then if sodium ethoxide is a better nucleophile than it is a base, right?
Edit: Ah maybe a substitution could occur since sodium ethoxide can function as a nucleophile ... the question is then if sodium ethoxide is a better nucleophile than it is a base, right?
You have a secondary alkyl iodide, not a tertiary, which means that the SN2 will be more competitive with the E2 than for tertiary alkyl iodides. The reading I have done indicates that if one uses a polar, aprotic solvent, one might tilt things toward the SN2. Can you give an example of such a solvent?
Both E2 and SN2 reactions are second order, kinetically. If one of the two were first order and the other one were second order, there would be a way to favor one process over the other by changing the concentrations of the reactants.
You have a secondary alkyl iodide, not a tertiary, which means that the SN2 will be more competitive with the E2 than for tertiary alkyl iodides. The reading I have done indicates that if one uses a polar, aprotic solvent, one might tilt things toward the SN2. Can you give an example of such a solvent?
Both E2 and SN2 reactions are second order, kinetically. If one of the two were first order and the other one were second order, there would be a way to favor one process over the other by changing the concentrations of the reactants.
Taking the base/nucleophile as a given, I was thinking more along the lines of conditions, such as solvent properties and temperature.
A couple of things:
* E2 reactions are favored for tertiary alkanes as SN2 reactions are rarely observed due to steric hindrance.
* My textbook also says that SN2 will be the main reaction if a weak base/good nucleophile is present, but E2 is favored if a strong base/good nucleophile is present. Since sodium ethoxide is both a strong base and good nucleophile, then E2 products are favored.
* The reaction kinetics of E2 aren't clearly laid out in my book, but SN2 reactions are characterized by a rate limiting step which requires a certain amount of activation energy to overcome, and as we know, activation energy decreases significantly with increase in temperature.
Just a couple of points.
2nd point indicates that the E2 products will be in exces.. Thank you.
Taking the base/nucleophile as a given, I was thinking more along the lines of conditions, such as solvent properties and temperature.
A couple of things:
* E2 reactions are favored for tertiary alkanes as SN2 reactions are rarely observed due to steric hindrance.
* My textbook also says that SN2 will be the main reaction if a weak base/good nucleophile is present, but E2 is favored if a strong base/good nucleophile is present. Since sodium ethoxide is both a strong base and good nucleophile, then E2 products are favored.
* The reaction kinetics of E2 aren't clearly laid out in my book, but SN2 reactions are characterized by a rate limiting step which requires a certain amount of activation energy to overcome, and as we know, activation energy decreases significantly with increase in temperature.
Just a couple of points.
2nd point indicates that the E2 products will be in exces.. Thank you.
That is a difficult question, because they are measured differently. Just for your own edification, how would you favor the SN2? How would you favor the E2?
An obvious choice is to select a strong nucleophile which is a weak base and vice versa as this would favor either SN2 or E2 products respectively.
That is a difficult question, because they are measured differently. Just for your own edification, how would you favor the SN2? How would you favor the E2?
An obvious choice is to select a strong nucleophile which is a weak base and vice versa as this would favor either SN2 or E2 products respectively.
I don't see how Zaitsev's rule comes into play when there is only one possible elimination product, but...
You're confusing me.
Zaitsev's rule is used if multiple products are available. But I don't see any other possible products from the information given (unless sodium ethoxide does something which I'm not aware of) and therefore, propene is just the major product?
I agree that there is only one elimination product. There is one other kind of reaction besides an elimination available to iodoalkanes.
I don't see how Zaitsev's rule comes into play when there is only one possible elimination product, but...
You're confusing me.
Zaitsev's rule is used if multiple products are available. But I don't see any other possible products from the information given (unless sodium ethoxide does something which I'm not aware of) and therefore, propene is just the major product?
I agree that there is only one elimination product. There is one other kind of reaction besides an elimination available to iodoalkanes.
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Zaitsev's rule is used if multiple products are available. But I don't see any other possible products from the information given (unless sodium ethoxide does something which I'm not aware of) and therefore, propene is just the major product?
Zaitsev's rule is used if multiple products are available. But I don't see any other possible products from the information given (unless sodium ethoxide does something which I'm not aware of) and therefore, propene is just the major product?
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Edit: Ah maybe a substitution could occur since sodium ethoxide can function as a nucleophile ... the question is then if sodium ethoxide is a better nucleophile than it is a base, right?
Edit: Ah maybe a substitution could occur since sodium ethoxide can function as a nucleophile ... the question is then if sodium ethoxide is a better nucleophile than it is a base, right?
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Both E2 and SN2 reactions are second order, kinetically. If one of the two were first order and the other one were second order, there would be a way to favor one process over the other by changing the concentrations of the reactants.
Both E2 and SN2 reactions are second order, kinetically. If one of the two were first order and the other one were second order, there would be a way to favor one process over the other by changing the concentrations of the reactants.
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* E2 reactions are favored for tertiary alkanes as SN2 reactions are rarely observed due to steric hindrance.
* My textbook also says that SN2 will be the main reaction if a weak base/good nucleophile is present, but E2 is favored if a strong base/good nucleophile is present. Since sodium ethoxide is both a strong base and good nucleophile, then E2 products are favored.
* The reaction kinetics of E2 aren't clearly laid out in my book, but SN2 reactions are characterized by a rate limiting step which requires a certain amount of activation energy to overcome, and as we know, activation energy decreases significantly with increase in temperature.
Just a couple of points.
2nd point indicates that the E2 products will be in exces.. Thank you.
* E2 reactions are favored for tertiary alkanes as SN2 reactions are rarely observed due to steric hindrance.
* My textbook also says that SN2 will be the main reaction if a weak base/good nucleophile is present, but E2 is favored if a strong base/good nucleophile is present. Since sodium ethoxide is both a strong base and good nucleophile, then E2 products are favored.
* The reaction kinetics of E2 aren't clearly laid out in my book, but SN2 reactions are characterized by a rate limiting step which requires a certain amount of activation energy to overcome, and as we know, activation energy decreases significantly with increase in temperature.
Just a couple of points.
2nd point indicates that the E2 products will be in exces.. Thank you.
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