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Glucose Isomers

Please help with the following problem.

When glucose is placed in water two stereoisomers are formed, one with the new OH on the opposite side of the ring than the 6th carbon, the α (alpha) isomer; and the other with the new OH group on the same side of the ring as the 6th carbon, β (beta) - anomer. Thus, a new chiral carbon is produced. However, even though the optical rotation of these two sugars is different, they are not of the same magnitude or are they opposite in direction. Is this the expected result?

Solution Preview

Yes, this is the expected result. The specific rotation of a freshly prepared solution of alpha-D-glucose is +112 degrees. The specific rotation of a freshly prepared solution of beta-D-glucose is +18.7 degrees.

The amount of rotation of an optically active compound is dependent on a number of factors:

1. the structure of the molecule
2. the temperature
3. the wavelength of light
4. the number of molecules in the path ...

Solution Summary

The solution discusses glucose isomers place in water.