2D-NMR capability may actually be an icing on the cake (high field 1D is all it takes in most cases, if the signals are assigned)... There are some methods proven to work for chiral carboxylic acids (see the attachment). In your case, making covalent derivatives of rosmarinic acid may require caution due to the acidity of the phenolic OH groups.
The problem is enantiomers have identical properties in an achiral environment.
So, there is no difference in normal NMR experiment.
Because enantiomers have different properties in a chiral environment, they can be distinguished in a chiral environment such as a chiral solvent, or complexed with a chiral shift reagent.
To solve your problem, if you know the reported specific rotation of the natural Rosmarinic acid, that seems to be thr R, you can just confirm the configuration checking the specific rotation.
NMR spectra of enantiomers are identical.
Therefore, neither 1D nir 2D NMR will offer any solution for you.
Only, in case of making diastereoisomers of your homochiral compound and comparing thier NMR properties with those of authentic samples, you would get the answer on your question. Therefore, a few classical methods exist (see NMR reviews on that topic).
Therefore, I´d like to join the opinion of Dr. Labadie and suggest that you determine the optical rotation. In case, that you have a pure sample with no other chiral constituents, this is an easy way to decide what you have.
Of course, all this (and much more) is covered in the reference file that has been provided in the first answer to this topic...
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