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What is a diastereotopic Proton?

What is a diastereotopic Proton?

Diastereotopic protons are chemically non equivalent protons that each produce distinct chemical shifts. Typically, this type of proton is of a CH2 group found in a chiral molecule, but it may also be found in the more subtly unique chemical environments of achiral compounds.

How do you determine if protons are diastereotopic?

The most common set of nonequivalent protons that you will hear bout in your course is going to be the diastereotopic protons. If replacing two protons with a different group (X) gives a pair of diastereomers, the protons are called Diastereotopic.

What are diastereotopic hydrogens?

The stereochemical term diastereotopic refers to the relationship between two groups in a molecule which, if replaced, would generate compounds that are diastereomers. Diastereotopic groups are often, but not always, identical groups attached to the same atom in a molecule containing at least one chiral center.

How do Enantiotopic and diastereotopic protons differ?

Enantiotopic protons normally have identical chemical shifts. However, when the molecule is placed in a chiral environment (say with an optically active solvent, co-solvent or Lewis acid) then the protons can become diastereotopic. This is in contrast to homotopic protons, which are always identical.

What are Enantiotopic and diastereotopic atoms?

Enantiotopic faces, atoms or groups look the same on their own, but will react differently with chiral molecules. Diastereotopic faces, atoms or groups always appear different.

How do you identify diastereotopic hydrogens?

Look at the molecule below – (R)-butan-2-ol. Replacement of the red H leads to the (R, R) product. Replacement of the blue H leads to the (R, S) product. Therefore, these two products are diastereomers, and the two protons are diastereotopic.

What is Prochirality example?

An achiral object which is capable of becoming chiral in two desymmetrisation steps is sometimes described as proprochiral. For example the proprochiral CH3CO2H becomes prochiral as CH2DCO2H and chiral as CHDTCO2H.

What are Enantiotopic ligands?

Two heterotopic ligands are enantiotopic if replacement of first one and then the other by. a different achiral ligand gives rise to two enantiomers. The same goes for addition to. enantiotopic faces.

Can methyl groups be diastereotopic?

It is achiral because its two methyl groups are equivalent. These two methyl groups are therefore enantiotopic….Prochirality and axial chirality.

a face, atom or group is… if its replacement leads to… distinguishable?
diastereotopic diastereomers always