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Is it possible, chemically, to change a dextrorotatory compound to its levorotatory counterpart? e.g. Is it possible to change levodopa to dextrodopa?

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Related, but not a duplicate: chemistry.stackexchange.com/questions/105/… – jonsca♦ Feb 11 at 5:37

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Yes,this process is called stereoconversion. Both SN1 and SN2 reactions can invert the chirality of a carbon center. In the case of the SN1 mechanism, departure of a leaving group generates a prochiral intermediate which is then open to nucleophilic attack on either face. If both faces are equally acessible to the nucleophile this will result in racemisation of the molecule. In the case of the SN2 reaction the nucleophile will enter a trigonal bipyramidal intermediate with the molecule. Assuming the nucleophile has the same stereochemical precedence as the leaving group, the stereochemistry will be inverted.

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Doesn't "dextrorotatory compound to levorotatory counterpart" mean we have to preserve the groups on the chiral carbon, rather than substituting one of the groups with another. – Aditya Sriram Jan 14 at 3:12
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@AdityaSriram - Yes, but if the leaving group and nucleophile are the same species, you're in the clear. This can happen in the case of keto-enol tautomerism at a stereocenter. – Richard Terrett Jan 14 at 4:03
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Adding an example to your answer will really help a lot. – Aditya Sriram Jan 14 at 5:29
@RichardTerrett I think Aditya Sriram is right you need to add an example not just of how you would change the chirality from dex to levo but how you would preserve the groups on the chiral carbon. – Brenton Horne Jan 14 at 5:42

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