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Why condensation reactions are energetically unfavourable while hydrolysis reactions are energetically favourable despite the fact that bond formation releases energy and bond breaking requires energy?
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+ Chemical reactions
+ Chemical bonds
+ Chemistry
+ Organic chemistry
+ Hydrolysis
+ Condensation
Posted by
Kieren Reeves
Why condensation reactions are energetically unfavourable while hydrolysis reactions are energetically favourable despite the fact that bond formation releases energy and bond breaking requires energy?
I think, OP, you meant “diethyl pentanedioate”. Otherwise, the compound doesn’t exist.
On the assumption that “yes”, a Dieckmann cyclization of diethyl pentanedioate (diethyl glutarate) would form a four-membered ring. There is too much ring strain involved in a four-membered ring (moreso one containing a ketone and thus “hoping for” a 120° bond angle) for the two ester groups to get it on.
More likely would be an intermolecular Claisen condensation, with the possibility of polymer formation. Not fun.
I think, OP, you meant “diethyl pentanedioate”. Otherwise, the compound doesn’t exist.
On the assumption that “yes”, a Dieckmann cyclization of diethyl pentanedioate (diethyl glutarate) would form a four-membered ring. There is too much ring strain involved in a four-membered ring (moreso one containing a ketone and thus “hoping for” a 120° bond angle) for the two ester groups to get it on.
More likely would be an intermolecular Claisen condensation, with the possibility of polymer formation. Not fun.
A lot of this has to do with the fact that arranging once- free particles in a specific pattern ( linked to one another, in the most simple case like beads on a necklace) is restricting their freedom and imposing and order , or pattern and thereby creating a less random system. That takes work , which in thermodynamic terms means a net decrease in Entropy or the natural “randomness”/ disorder of a system (delta lS)
This tendency countervails the energy released when there are more stable bonds being formed, such that an overall pprocess has less tendency than otherwise to occur unaided by outside input ( it’s less “spontaneou00s” or “exergonic”. The latter refers to a negative Free Energy change. Look up :
“ Gibbs Free Energy. or “delta G”.
Delta G = delta H - absoluteT in Kelvin x net entropy change, which is “delta S”.
A lot of this has to do with the fact that arranging once- free particles in a specific pattern ( linked to one another, in the most simple case like beads on a necklace) is restricting their freedom and imposing and order , or pattern and thereby creating a less random system. That takes work , which in thermodynamic terms means a net decrease in Entropy or the natural “randomness”/ disorder of a system (delta lS)
This tendency countervails the energy released when there are more stable bonds being formed, such that an overall pprocess has less tendency than otherwise to occur unaided by outside input ( it’s less “spontaneou00s” or “exergonic”. The latter refers to a negative Free Energy change. Look up :
“ Gibbs Free Energy. or “delta G”.
Delta G = delta H - absoluteT in Kelvin x net entropy change, which is “delta S”.
I think, OP, you meant “diethyl pentanedioate”. Otherwise, the compound doesn’t exist.
On the assumption that “yes”, a Dieckmann cyclization of diethyl pentanedioate (diethyl glutarate) would form a four-membered ring. There is too much ring strain involved in a four-membered ring (moreso one containing a ketone and thus “hoping for” a 120° bond angle) for the two ester groups to get it on.
More likely would be an intermolecular Claisen condensation, with the possibility of polymer formation. Not fun.
I think, OP, you meant “diethyl pentanedioate”. Otherwise, the compound doesn’t exist.
On the assumption that “yes”, a Dieckmann cyclization of diethyl pentanedioate (diethyl glutarate) would form a four-membered ring. There is too much ring strain involved in a four-membered ring (moreso one containing a ketone and thus “hoping for” a 120° bond angle) for the two ester groups to get it on.
More likely would be an intermolecular Claisen condensation, with the possibility of polymer formation. Not fun.
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A lot of this has to do with the fact that arranging once- free particles in a specific pattern ( linked to one another, in the most simple case like beads on a necklace) is restricting their freedom and imposing and order , or pattern and thereby creating a less random system. That takes work , which in thermodynamic terms means a net decrease in Entropy or the natural “randomness”/ disorder of a system (delta lS)
This tendency countervails the energy released when there are more stable bonds being formed, such that an overall pprocess has less tendency than otherwise to occur unaided by outside input ( it’s less “spontaneou00s” or “exergonic”. The latter refers to a negative Free Energy change. Look up :
“ Gibbs Free Energy. or “delta G”.
Delta G = delta H - absoluteT in Kelvin x net entropy change, which is “delta S”.
A lot of this has to do with the fact that arranging once- free particles in a specific pattern ( linked to one another, in the most simple case like beads on a necklace) is restricting their freedom and imposing and order , or pattern and thereby creating a less random system. That takes work , which in thermodynamic terms means a net decrease in Entropy or the natural “randomness”/ disorder of a system (delta lS)
This tendency countervails the energy released when there are more stable bonds being formed, such that an overall pprocess has less tendency than otherwise to occur unaided by outside input ( it’s less “spontaneou00s” or “exergonic”. The latter refers to a negative Free Energy change. Look up :
“ Gibbs Free Energy. or “delta G”.
Delta G = delta H - absoluteT in Kelvin x net entropy change, which is “delta S”.
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