Do diastereomers have different physical properties
Answers
Answer:
In a pair of diastereomers, some chiral centers are the same and some are opposite. The molecule is neither identical to nor the mirror image of its diastereomer.
Threitol is a metabolite closely related to carbohydrates. D-threitol is the enantiomer of L-threitol. The two are non-identical, but they are mirror images of each other. Both compounds can be crystallized, forming needle-like crystals. Both have melting points of 88-89oC. D-threose has an optical rotation [a]D= - 4.0 (c, 7 in H2O, but L-threose has an optical rotation [a]D= + 4.6 (c, 6 in H2O). You might notice that these two numbers are not exactly opposites, but if you have ever tried measuring an optical rotation yourself, you know that this is pretty good.
Diastereomers have different physical properties (different melting points, boiling points, solubilities, etc.). Their chemical properties also differ in that they react with reagents at different rates. Thus, they can be directly separated by chromatographic methods without the need for chiral reagents.
Explanation:
And as different chemical compounds, diastereomers have different chemical and physical properties. The differential solubility is the property commonly exploited to effect a separation of the diastereomers.