If a compound has enantiotopic and homotopic hydrogens, how will the NMR spectra differ in the chiral and achiral medium?
Homotopic Hs are the same even in a choral environment - so same chemical shift. Enantiotopic Hs will be different and have slightly different Chemical shifts in a chiral environment like a chiral solvent.
Homotopic groups are always equivalent. Enantiotopic groups are the same except when they are placed in chiral environments.
Dear Sujeesh, just a tiny add-on to what has been said: Enantiotopic groups MAY have different chemical shifts in a chiral environment (solvent), but this does not always have to be the case!
Hello Dear!
📷 If replacing two protons with a different group (Y) gives a pair of enantiomers, the protons are called Enantiotopic, which can form chiral center. For example, chloromethanol if two protons (Ha and Hb) replaced with other different group like Br…, it forms a chiral center and also at this condition we may not get same peak for both protons in the NMR spectra.
📷 For example, all the protons in ethane are homotopic. That all the protons appear in the same environment.
If replacing two protons with a different group (X) gives the same compound, the protons are called Homotopic. At this condition achiral center formed instead of chiral center. Hence, both protons in the NMR spectra have one signal.
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