Home > Community > What makes the cyclic structure of glucose more stable than the open chain structure?
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+ Biochemistry
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Justin Harper

What makes the cyclic structure of glucose more stable than the open chain structure?

Benjamin van As  Follow

You get to form a C-O $\mathrm{\sigma}$ bond at the expense of a C-O $\mathrm{\pi}$ bond. The single bond has a higher bond energy, even though it is somewhat de-stabilized by the anomeric effect. It's still an overall win, despite taking the entropic hit to confine your molecule into a ring.

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Georgios Margaritis  Follow
You should have More
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Gaer Strom  Follow
Irrelevant was the wrong word. I meant to say that taking into account the entropic effect, it becomes temperature-dependent, and no temperature was specified.More
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James Wasvary  Follow
a prioriMore
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Emile de Groot  Follow
than carbons with multiple bonds.More
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Jesse Raffield  Follow
@Karl Thats not correct. The free energy difference between the open-chain and ring forms has a entropic component because the open-chain has more degrees of freedom.More
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Boris Bartlog  Follow

The carbon atoms in the gulucose ring each have four covalent bonds ......it follows,therefore,that the gulucose molecule will be at its most stable when all carbon atoms can arrange themselves , so that their bond angles are all close to 109.5 degree .

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Google SEO.  Follow
This is incorrect. There is nothing about four single bonds on carbon that would be inherently more stable than multiple bonds.More
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